slick.grid.js

/**
 * @license
 * (c) 2009-2013 Michael Leibman
 * michael{dot}leibman{at}gmail{dot}com
 * http://github.com/mleibman/slickgrid
 *
 * Distributed under MIT license.
 * All rights reserved.
 *
 * SlickGrid v2.2
 *
 * NOTES:
 *     Cell/row DOM manipulations are done directly bypassing jQuery's DOM manipulation methods.
 *     This increases the speed dramatically, but can only be done safely because there are no event handlers
 *     or data associated with any cell/row DOM nodes.  Cell editors must make sure they implement .destroy()
 *     and do proper cleanup.
 */

// make sure required JavaScript modules are loaded
if (typeof jQuery === "undefined") {
    throw "SlickGrid requires jquery module to be loaded";
}
if (!jQuery.fn.drag) {
    throw "SlickGrid requires jquery.event.drag module to be loaded";
}
if (typeof Slick === "undefined") {
    throw "slick.core.js not loaded";
}


(function ($) {
    // Slick.Grid
    $.extend(true, window, {
        Slick: {
            Grid: SlickGrid
        }
    });

    // shared across all grids on the page
    var scrollbarDimensions;
    var maxSupportedCssHeight;  // browser's breaking point

    //////////////////////////////////////////////////////////////////////////////////////////////
    // SlickGrid class implementation (available as Slick.Grid)

    /**
     * Creates a new instance of the grid.
     * @class SlickGrid
     * @constructor
     * @param {Node}              container   Container node to create the grid in.
     * @param {Array,Object}      data        An array of objects for databinding.
     * @param {Array}             columns     An array of column definitions.
     * @param {Object}            options     Grid options.
     **/
    function SlickGrid(container, data, columns, options) {
        // settings
        var defaults = {
            explicitInitialization: false,
            rowHeight: 25,
            defaultColumnWidth: 80,
            enableAddRow: false,
            leaveSpaceForNewRows: false,
            editable: false,
            autoEdit: true,
            enableCellNavigation: true,
            enableColumnReorder: true,
            asyncEditorLoading: false,
            asyncEditorLoadDelay: 100,
            forceFitColumns: false,
            enableAsyncPostRender: false,
            asyncPostRenderDelay: 50,
            enableAsyncPostRenderCleanup: false,
            asyncPostRenderCleanupDelay: 40,
            autoHeight: false,
            editorLock: Slick.GlobalEditorLock,
            showHeaderRow: false,
            headerRowHeight: 25,
            showTopPanel: false,
            topPanelHeight: 25,
            formatterFactory: null,
            editorFactory: null,
            cellFlashingCssClass: "flashing",
            selectedCellCssClass: "selected",
            multiSelect: true,
            enableTextSelectionOnCells: false,
            dataItemColumnValueExtractor: null,
            fullWidthRows: false,
            multiColumnSort: false,
            defaultFormatter: defaultFormatter,
            forceSyncScrolling: false,
            addNewRowCssClass: "new-row",
            minimumContainerHeight: null
        };

        var columnDefaults = {
            name: "",
            resizable: true,
            sortable: false,
            minWidth: 30,
            rerenderOnResize: false,
            headerCssClass: null,
            defaultSortAsc: true,
            focusable: true,
            selectable: true,
            preventClearOnEdit: false
        };

        // scroller
        var th;   // virtual height
        var h;    // real scrollable height
        var ph;   // page height
        var n;    // number of pages
        var cj;   // "jumpiness" coefficient

        var page = 0;       // current page
        var offset = 0;     // current page offset
        var vScrollDir = 1;

        // private
        var initialized = false;
        var $container;
        var uid = "slickgrid_" + Math.round(1000000 * Math.random());
        var self = this;
        var $focusSink, $focusSink2;
        var $headerScroller;
        var $headers;
        var $headerRow, $headerRowScroller, $headerRowSpacer;
        var $topPanelScroller;
        var $topPanel;
        var $viewport;
        var $canvas;
        var $style;
        var $boundAncestors;
        var stylesheet, columnCssRulesL, columnCssRulesR;
        var viewportH, viewportW;
        var canvasWidth;
        var viewportHasHScroll, viewportHasVScroll;
        var headerColumnWidthDiff = 0, headerColumnHeightDiff = 0, // border+padding
            cellWidthDiff = 0, cellHeightDiff = 0, jQueryNewWidthBehaviour = false;
        var absoluteColumnMinWidth;

        var tabbingDirection = 1;
        var activePosX;
        var activeRow, activeCell;
        var activeCellNode = null;
        var currentEditor = null;
        var serializedEditorValue;
        var editController;

        var rowsCache = {};
        var renderedRows = 0;
        var numVisibleRows;
        var prevScrollTop = 0;
        var scrollTop = 0;
        var lastRenderedScrollTop = 0;
        var lastRenderedScrollLeft = 0;
        var prevScrollLeft = 0;
        var scrollLeft = 0;

        var selectionModel;
        var selectedRows = [];

        var plugins = [];
        var cellCssClasses = {};

        var columnsById = {};
        var sortColumns = [];
        var columnPosLeft = [];
        var columnPosRight = [];


        // async call handles
        var h_editorLoader = null;
        var h_render = null;
        var h_postrender = null;
        var h_postrenderCleanup = null;
        var postProcessedRows = {};
        var postProcessToRow = null;
        var postProcessFromRow = null;
        var postProcessedCleanupQueue = [];
        var postProcessgroupId = 0;

        // perf counters
        var counter_rows_rendered = 0;
        var counter_rows_removed = 0;

        // These two variables work around a bug with inertial scrolling in Webkit/Blink on Mac.
        // See http://crbug.com/312427.
        var rowNodeFromLastMouseWheelEvent;  // this node must not be deleted while inertial scrolling
        var zombieRowNodeFromLastMouseWheelEvent;  // node that was hidden instead of getting deleted
        var zombieRowCacheFromLastMouseWheelEvent;  // row cache for above node
        var zombieRowPostProcessedFromLastMouseWheelEvent;  // post processing references for above node

        // store css attributes if display:none is active in container or parent
        var cssShow = { position: 'absolute', visibility: 'hidden', display: 'block' };
        var $hiddenParents;
        var oldProps = [];
        var isOutsideEventFired = true;

        //////////////////////////////////////////////////////////////////////////////////////////////
        // Initialization

        function init() {
            $container = $(container);
            if ($container.length < 1) {
                throw new Error("SlickGrid requires a valid container, " + container + " does not exist in the DOM.");
            }


            cacheCssForHiddenInit();

            // calculate these only once and share between grid instances
            maxSupportedCssHeight = maxSupportedCssHeight || getMaxSupportedCssHeight();
            scrollbarDimensions = scrollbarDimensions || measureScrollbar();

            options = $.extend({}, defaults, options);

            if (options.minimumContainerHeight && $container.height() < options.minimumContainerHeight) {
                $container.height(options.minimumContainerHeight)
            }

            validateAndEnforceOptions();
            columnDefaults.width = options.defaultColumnWidth;

            columnsById = {};
            for (var i = 0; i < columns.length; i++) {
                var m = columns[i] = $.extend({}, columnDefaults, columns[i]);
                columnsById[m.id] = i;
                if (m.minWidth && m.width < m.minWidth) {
                    m.width = m.minWidth;
                }
                if (m.maxWidth && m.width > m.maxWidth) {
                    m.width = m.maxWidth;
                }
            }

            // validate loaded JavaScript modules against requested options
            if (options.enableColumnReorder && !$.fn.sortable) {
                throw new Error("SlickGrid's 'enableColumnReorder = true' option requires jquery-ui.sortable module to be loaded");
            }

            editController = {
                "commitCurrentEdit": commitCurrentEdit,
                "cancelCurrentEdit": cancelCurrentEdit
            };

            $container
                .empty()
                .css("overflow", "hidden")
                .css("outline", 0)
                .addClass(uid)
                .addClass("ui-widget");

            // set up a positioning container if needed
            if (!/relative|absolute|fixed/.test($container.css("position"))) {
                $container.css("position", "relative");
            }

            $focusSink = $("<div tabIndex='0' hideFocus style='position:fixed;width:0;height:0;top:0;left:0;outline:0;'></div>").appendTo($container);

            $headerScroller = $("<div class='slick-header ui-state-default' style='overflow:hidden;position:relative;' />").appendTo($container);
            $headers = $("<div class='slick-header-columns' style='left:-1000px' />").appendTo($headerScroller);
            $headers.width(getHeadersWidth());

            $headerRowScroller = $("<div class='slick-headerrow ui-state-default' style='overflow:hidden;position:relative;' />").appendTo($container);
            $headerRow = $("<div class='slick-headerrow-columns' />").appendTo($headerRowScroller);
            $headerRowSpacer = $("<div style='display:block;height:1px;position:absolute;top:0;left:0;'></div>")
                .css("width", getCanvasWidth() + scrollbarDimensions.width + "px")
                .appendTo($headerRowScroller);

            $topPanelScroller = $("<div class='slick-top-panel-scroller ui-state-default' style='overflow:hidden;position:relative;' />").appendTo($container);
            $topPanel = $("<div class='slick-top-panel' style='width:10000px' />").appendTo($topPanelScroller);

            if (!options.showTopPanel) {
                $topPanelScroller.hide();
            }

            if (!options.showHeaderRow) {
                $headerRowScroller.hide();
            }

            $viewport = $("<div class='slick-viewport' style='width:100%;overflow:auto;outline:0;position:relative;;'>").appendTo($container);
            $viewport.css("overflow-y", options.autoHeight ? "hidden" : "auto");

            $canvas = $("<div class='grid-canvas' />").appendTo($viewport);

            $focusSink2 = $focusSink.clone().appendTo($container);

            if (!options.explicitInitialization) {
                finishInitialization();
            }
        }

        function finishInitialization() {
            if (!initialized) {
                initialized = true;

                viewportW = parseFloat($.css($container[0], "width", true));

                // header columns and cells may have different padding/border skewing width calculations (box-sizing, hello?)
                // calculate the diff so we can set consistent sizes
                measureCellPaddingAndBorder();

                // for usability reasons, all text selection in SlickGrid is disabled
                // with the exception of input and textarea elements (selection must
                // be enabled there so that editors work as expected); note that
                // selection in grid cells (grid body) is already unavailable in
                // all browsers except IE
                disableSelection($headers); // disable all text selection in header (including input and textarea)

                if (!options.enableTextSelectionOnCells) {
                    // disable text selection in grid cells except in input and textarea elements
                    // (this is IE-specific, because selectstart event will only fire in IE)
                    $viewport.bind("selectstart.ui", function (event) {
                        return $(event.target).is("input,textarea");
                    });
                }

                updateColumnCaches();
                createColumnHeaders();
                setupColumnSort();
                createCssRules();
                resizeCanvas();
                bindAncestorScrollEvents();

                $container
                    .bind("resize.slickgrid", resizeCanvas)
                    .bind("click", function () {
                        isOutsideEventFired = false;
                    });

                //In case the click is outside the grid

                $(document).on('click touchstart', function (ev) {
                    if (!$container.is(ev.target) && $container.has(ev.target).length === 0 && !isOutsideEventFired) {
                        outsideClickHandler(ev);
                    }
                });

                $viewport
                    //.bind("click", handleClick)
                    .bind("scroll", handleScroll);
                $headerScroller
                    .bind("contextmenu", handleHeaderContextMenu)
                    .bind("click", handleHeaderClick)
                    .delegate(".slick-header-column", "mouseenter", handleHeaderMouseEnter)
                    .delegate(".slick-header-column", "mouseleave", handleHeaderMouseLeave);
                $headerRowScroller
                    .bind("scroll", handleHeaderRowScroll);
                $focusSink.add($focusSink2)
                    .bind("keydown", handleKeyDown);
                $canvas
                    .bind("keydown", handleKeyDown)
                    .bind("click", handleClick)
                    .bind("dblclick", handleDblClick)
                    .bind("contextmenu", handleContextMenu)
                    .bind("draginit", handleDragInit)
                    .bind("dragstart", {distance: 3}, handleDragStart)
                    .bind("drag", handleDrag)
                    .bind("dragend", handleDragEnd)
                    .delegate(".slick-cell", "mouseenter", handleMouseEnter)
                    .delegate(".slick-cell", "mouseleave", handleMouseLeave);

                // Work around http://crbug.com/312427.
                if (navigator.userAgent.toLowerCase().match(/webkit/) &&
                    navigator.userAgent.toLowerCase().match(/macintosh/)) {
                    $canvas.bind("mousewheel", handleMouseWheel);
                }
                restoreCssFromHiddenInit();
                trigger(self.onInitialize, {grid: self});
            }
        }

        function getUID() {
            return uid;
        }

        /**
         * All custom jquery events will have "slick:" prefix
         * @param eventName
         */
        function addCustomEvent(eventName) {

            // A jQuery object containing all elements to which the "outside" event is
            // bound.
            var elements = $(),
            // The "originating" event, namespaced for easy unbinding.
                eventNameSpaced = 'slick:' + eventName + '-custom-event-' + getUID();

            $.event.special[eventName] = {
                // Called only when the first "outside" event callback is bound per
                // element.
                namespace: eventNameSpaced,
                setup: function () {
                    // Add this element to the list of elements to which this "outside"
                    // event is bound.
                    elements = elements.add(this);
                    // If this is the first element getting the event bound, bind a handler
                    // to document to catch all corresponding "originating" events.
                    if (elements.length === 1) {
                        $(document).bind(eventNameSpaced, function (ev) {
                            // Iterate over all elements to which this "outside" event is bound.
                            $(elements).each(function () {
                                var elem = $(this);
                                // If this element isn't the element on which the event was triggered,
                                // and this element doesn't contain said element, then said element is
                                // considered to be outside, and the "outside" event will be triggered!
                                if (this !== ev.target && !elem.has(ev.target).length) {
                                    // Use triggerHandler instead of trigger so that the "outside" event
                                    // doesn't bubble. Pass in the "originating" event's .target so that
                                    // the "outside" event.target can be overridden with something more
                                    // meaningful.
                                    debugger;
                                    elem.triggerHandler(eventName, [ev.target]);
                                }
                            });
                        });
                    }
                },

                // Called only when the last "outside" event callback is unbound per
                // element.
                teardown: function () {

                    // Remove this element from the list of elements to which this
                    // "outside" event is bound.
                    elements = elements.not(this);

                    // If this is the last element removed, remove the "originating" event
                    // handler on document that powers this "outside" event.
                    if (elements.length === 0) {
                        $(document).unbind(eventNameSpaced);
                    }
                },

                // Called every time a "outside" event callback is bound to an element.
                add: function (handleObj) {
                    var old_handler = handleObj.handler;

                    // This function is executed every time the event is triggered. This is
                    // used to override the default event.target reference with one that is
                    // more useful.
                    handleObj.handler = function (event, elem) {

                        // Set the event object's .target property to the element that the
                        // user interacted with, not the element that the "outside" event was
                        // was triggered on.
                        event.target = elem;

                        // Execute the actual bound handler.
                        old_handler.apply(this, arguments);
                    };
                }
            }
            return eventName;
        }

        function cacheCssForHiddenInit() {
            // handle display:none on container or container parents
            $hiddenParents = $container.parents().andSelf().not(':visible');
            $hiddenParents.each(function () {
                var old = {};
                for (var name in cssShow) {
                    old[ name ] = this.style[ name ];
                    this.style[ name ] = cssShow[ name ];
                }
                oldProps.push(old);
            });
        }

        function restoreCssFromHiddenInit() {
            // finish handle display:none on container or container parents
            // - put values back the way they were
            $hiddenParents.each(function (i) {
                var old = oldProps[i];
                for (var name in cssShow) {
                    this.style[ name ] = old[ name ];
                }
            });
        }

        function registerPlugin(plugin) {
            plugins.unshift(plugin);
            plugin.init(self);
        }

        function unregisterPlugin(plugin) {
            for (var i = plugins.length; i >= 0; i--) {
                if (plugins[i] === plugin) {
                    if (plugins[i].destroy) {
                        plugins[i].destroy();
                    }
                    plugins.splice(i, 1);
                    break;
                }
            }
        }

        function setSelectionModel(model) {
            if (selectionModel) {
                selectionModel.onSelectedRangesChanged.unsubscribe(handleSelectedRangesChanged);
                if (selectionModel.destroy) {
                    selectionModel.destroy();
                }
            }

            selectionModel = model;
            if (selectionModel) {
                selectionModel.init(self);
                selectionModel.onSelectedRangesChanged.subscribe(handleSelectedRangesChanged);
            }
        }

        function getSelectionModel() {
            return selectionModel;
        }

        function getCanvasNode() {
            return $canvas[0];
        }

        function measureScrollbar() {
            var $c = $("<div style='position:absolute; top:-10000px; left:-10000px; width:100px; height:100px; overflow:scroll;'></div>").appendTo("body");
            var dim = {
                width: $c.width() - $c[0].clientWidth,
                height: $c.height() - $c[0].clientHeight
            };
            $c.remove();
            return dim;
        }

        function getHeadersWidth() {
            var headersWidth = 0;
            for (var i = 0, ii = columns.length; i < ii; i++) {
                var width = columns[i].width;
                headersWidth += width;
            }
            headersWidth += scrollbarDimensions.width;
            return Math.max(headersWidth, viewportW) + 1000;
        }

        function getCanvasWidth() {
            var availableWidth = viewportHasVScroll ? viewportW - scrollbarDimensions.width : viewportW;
            var rowWidth = 0;
            var i = columns.length;
            while (i--) {
                rowWidth += columns[i].width;
            }
            return options.fullWidthRows ? Math.max(rowWidth, availableWidth) : rowWidth;
        }

        function updateCanvasWidth(forceColumnWidthsUpdate) {
            var oldCanvasWidth = canvasWidth;
            canvasWidth = getCanvasWidth();

            if (canvasWidth != oldCanvasWidth) {
                $canvas.width(canvasWidth);
                $headerRow.width(canvasWidth);
                $headers.width(getHeadersWidth());
                viewportHasHScroll = (canvasWidth > viewportW - scrollbarDimensions.width);
            }

            $headerRowSpacer.width(canvasWidth + (viewportHasVScroll ? scrollbarDimensions.width : 0));

            if (canvasWidth != oldCanvasWidth || forceColumnWidthsUpdate) {
                applyColumnWidths();
            }
        }

        function disableSelection($target) {
            if ($target && $target.jquery) {
                $target
                    .attr("unselectable", "on")
                    .css("MozUserSelect", "none")
                    .bind("selectstart.ui", function () {
                        return false;
                    }); // from jquery:ui.core.js 1.7.2
            }
        }

        function getMaxSupportedCssHeight() {
            var supportedHeight = 1000000;
            // FF reports the height back but still renders blank after ~6M px
            var testUpTo = navigator.userAgent.toLowerCase().match(/firefox/) ? 6000000 : 1000000000;
            var div = $("<div style='display:none' />").appendTo(document.body);

            while (true) {
                var test = supportedHeight * 2;
                div.css("height", test);
                if (test > testUpTo || div.height() !== test) {
                    break;
                } else {
                    supportedHeight = test;
                }
            }

            div.remove();
            return supportedHeight;
        }

        // TODO:  this is static.  need to handle page mutation.
        function bindAncestorScrollEvents() {
            var elem = $canvas[0];
            while ((elem = elem.parentNode) != document.body && elem != null) {
                // bind to scroll containers only
                if (elem == $viewport[0] || elem.scrollWidth != elem.clientWidth || elem.scrollHeight != elem.clientHeight) {
                    var $elem = $(elem);
                    if (!$boundAncestors) {
                        $boundAncestors = $elem;
                    } else {
                        $boundAncestors = $boundAncestors.add($elem);
                    }
                    $elem.bind("scroll." + uid, handleActiveCellPositionChange);
                }
            }
        }

        function unbindAncestorScrollEvents() {
            if (!$boundAncestors) {
                return;
            }
            $boundAncestors.unbind("scroll." + uid);
            $boundAncestors = null;
        }

        function updateColumnHeader(columnId, title, toolTip) {
            if (!initialized) {
                return;
            }
            var idx = getColumnIndex(columnId);
            if (idx == null) {
                return;
            }

            var columnDef = columns[idx];
            var $header = $headers.children().eq(idx);
            if ($header) {
                if (title !== undefined) {
                    columns[idx].name = title;
                }
                if (toolTip !== undefined) {
                    columns[idx].toolTip = toolTip;
                }

                trigger(self.onBeforeHeaderCellDestroy, {
                    "node": $header[0],
                    "column": columnDef,
                    "grid": self
                });

                $header
                    .attr("title", toolTip || "")
                    .children().eq(0).html(title);

                trigger(self.onHeaderCellRendered, {
                    "node": $header[0],
                    "column": columnDef,
                    "grid": self
                });
            }
        }

        function getHeaderRow() {
            return $headerRow[0];
        }

        function getHeaderRowColumn(columnId) {
            var idx = getColumnIndex(columnId);
            var $header = $headerRow.children().eq(idx);
            return $header && $header[0];
        }

        function createColumnHeaders() {
            function onMouseEnter() {
                $(this).addClass("ui-state-hover");
            }

            function onMouseLeave() {
                $(this).removeClass("ui-state-hover");
            }

            $headers.find(".slick-header-column")
                .each(function () {
                    var columnDef = $(this).data("column");
                    if (columnDef) {
                        trigger(self.onBeforeHeaderCellDestroy, {
                            "node": this,
                            "column": columnDef,
                            "grid": self
                        });
                    }
                });
            $headers.empty();
            $headers.width(getHeadersWidth());

            $headerRow.find(".slick-headerrow-column")
                .each(function () {
                    var columnDef = $(this).data("column");
                    if (columnDef) {
                        trigger(self.onBeforeHeaderRowCellDestroy, {
                            "node": this,
                            "column": columnDef,
                            "grid": self
                        });
                    }
                });
            $headerRow.empty();

            for (var i = 0; i < columns.length; i++) {
                var m = columns[i];

                var header = $("<div class='ui-state-default slick-header-column' />")
                    .html("<span class='slick-column-name'>" + m.name + "</span>")
                    .outerWidth(m.width - headerColumnWidthDiff)
                    .attr("id", "" + uid + m.id)
                    .attr("title", m.toolTip || "")
                    .data("column", m)
                    .addClass(m.headerCssClass || "")
                    .appendTo($headers);

                if (options.enableColumnReorder || m.sortable) {
                    header
                        .on('mouseenter', onMouseEnter)
                        .on('mouseleave', onMouseLeave);
                }

                if (m.sortable) {
                    header.addClass("slick-header-sortable");
                    header.append("<span class='slick-sort-indicator' />");
                }

                trigger(self.onHeaderCellRendered, {
                    "node": header[0],
                    "column": m,
                    "grid": self
                });

                if (options.showHeaderRow) {
                    var headerRowCell = $("<div class='ui-state-default slick-headerrow-column l" + i + " r" + i + "'></div>")
                        .data("column", m)
                        .appendTo($headerRow);

                    trigger(self.onHeaderRowCellRendered, {
                        "node": headerRowCell[0],
                        "column": m,
                        "grid": self
                    });
                }
            }

            setSortColumns(sortColumns);
            setupColumnResize();
            if (options.enableColumnReorder) {
                setupColumnReorder();
            }
        }

        function setupColumnSort() {
            $headers.click(function (e) {
                // temporary workaround for a bug in jQuery 1.7.1 (http://bugs.jquery.com/ticket/11328)
                e.metaKey = e.metaKey || e.ctrlKey;

                if ($(e.target).hasClass("slick-resizable-handle")) {
                    return;
                }

                var $col = $(e.target).closest(".slick-header-column");
                if (!$col.length) {
                    return;
                }

                var column = $col.data("column");
                if (column.sortable) {
                    if (!getEditorLock().commitCurrentEdit()) {
                        return;
                    }

                    var sortOpts = null;
                    var i = 0;
                    for (; i < sortColumns.length; i++) {
                        if (sortColumns[i].columnId == column.id) {
                            sortOpts = sortColumns[i];
                            sortOpts.sortAsc = !sortOpts.sortAsc;
                            break;
                        }
                    }

                    if (e.metaKey && options.multiColumnSort) {
                        if (sortOpts) {
                            sortColumns.splice(i, 1);
                        }
                    }
                    else {
                        if ((!e.shiftKey && !e.metaKey) || !options.multiColumnSort) {
                            sortColumns = [];
                        }

                        if (!sortOpts) {
                            sortOpts = { columnId: column.id, sortAsc: column.defaultSortAsc };
                            sortColumns.push(sortOpts);
                        } else if (sortColumns.length == 0) {
                            sortColumns.push(sortOpts);
                        }
                    }

                    setSortColumns(sortColumns);

                    if (!options.multiColumnSort) {
                        trigger(self.onSort, {
                            multiColumnSort: false,
                            sortCol: column,
                            sortAsc: sortOpts.sortAsc,
                            grid: self}, e);
                    } else {
                        trigger(self.onSort, {
                            multiColumnSort: true,
                            sortCols: $.map(sortColumns, function (col) {
                                return {sortCol: columns[getColumnIndex(col.columnId)], sortAsc: col.sortAsc };
                            }),
                            grid: self}, e);
                    }
                }
            });
        }

        function setupColumnReorder() {
            $headers.filter(":ui-sortable").sortable("destroy");
            $headers.sortable({
                containment: "parent",
                distance: 3,
                axis: "x",
                cursor: "default",
                tolerance: "intersection",
                helper: "clone",
                placeholder: "slick-sortable-placeholder ui-state-default slick-header-column",
                start: function (e, ui) {
                    ui.placeholder.width(ui.helper.outerWidth() - headerColumnWidthDiff);
                    $(ui.helper).addClass("slick-header-column-active");
                },
                beforeStop: function (e, ui) {
                    $(ui.helper).removeClass("slick-header-column-active");
                },
                stop: function (e) {
                    if (!getEditorLock().commitCurrentEdit()) {
                        $(this).sortable("cancel");
                        return;
                    }

                    var reorderedIds = $headers.sortable("toArray");
                    var reorderedColumns = [];
                    for (var i = 0; i < reorderedIds.length; i++) {
                        reorderedColumns.push(columns[getColumnIndex(reorderedIds[i].replace(uid, ""))]);
                    }
                    setColumns(reorderedColumns);

                    trigger(self.onColumnsReordered, {grid: self});
                    e.stopPropagation();
                    setupColumnResize();
                }
            });
        }

        function setupColumnResize() {
            var $col, j, c, pageX, columnElements, minPageX, maxPageX, firstResizable, lastResizable;
            columnElements = $headers.children();
            columnElements.find(".slick-resizable-handle").remove();
            columnElements.each(function (i, e) {
                if (columns[i].resizable) {
                    if (firstResizable === undefined) {
                        firstResizable = i;
                    }
                    lastResizable = i;
                }
            });
            if (firstResizable === undefined) {
                return;
            }
            columnElements.each(function (i, e) {
                if (i < firstResizable || (options.forceFitColumns && i >= lastResizable)) {
                    return;
                }
                $col = $(e);
                $("<div class='slick-resizable-handle' />")
                    .appendTo(e)
                    .bind("dragstart", function (e, dd) {
                        if (!getEditorLock().commitCurrentEdit()) {
                            return false;
                        }
                        pageX = e.pageX;
                        $(this).parent().addClass("slick-header-column-active");
                        var shrinkLeewayOnRight = null, stretchLeewayOnRight = null;
                        // lock each column's width option to current width
                        columnElements.each(function (i, e) {
                            columns[i].previousWidth = $(e).outerWidth();
                        });
                        if (options.forceFitColumns) {
                            shrinkLeewayOnRight = 0;
                            stretchLeewayOnRight = 0;
                            // colums on right affect maxPageX/minPageX
                            for (j = i + 1; j < columnElements.length; j++) {
                                c = columns[j];
                                if (c.resizable) {
                                    if (stretchLeewayOnRight !== null) {
                                        if (c.maxWidth) {
                                            stretchLeewayOnRight += c.maxWidth - c.previousWidth;
                                        } else {
                                            stretchLeewayOnRight = null;
                                        }
                                    }
                                    shrinkLeewayOnRight += c.previousWidth - Math.max(c.minWidth || 0, absoluteColumnMinWidth);
                                }
                            }
                        }
                        var shrinkLeewayOnLeft = 0, stretchLeewayOnLeft = 0;
                        for (j = 0; j <= i; j++) {
                            // columns on left only affect minPageX
                            c = columns[j];
                            if (c.resizable) {
                                if (stretchLeewayOnLeft !== null) {
                                    if (c.maxWidth) {
                                        stretchLeewayOnLeft += c.maxWidth - c.previousWidth;
                                    } else {
                                        stretchLeewayOnLeft = null;
                                    }
                                }
                                shrinkLeewayOnLeft += c.previousWidth - Math.max(c.minWidth || 0, absoluteColumnMinWidth);
                            }
                        }
                        if (shrinkLeewayOnRight === null) {
                            shrinkLeewayOnRight = 100000;
                        }
                        if (shrinkLeewayOnLeft === null) {
                            shrinkLeewayOnLeft = 100000;
                        }
                        if (stretchLeewayOnRight === null) {
                            stretchLeewayOnRight = 100000;
                        }
                        if (stretchLeewayOnLeft === null) {
                            stretchLeewayOnLeft = 100000;
                        }
                        maxPageX = pageX + Math.min(shrinkLeewayOnRight, stretchLeewayOnLeft);
                        minPageX = pageX - Math.min(shrinkLeewayOnLeft, stretchLeewayOnRight);
                    })
                    .bind("drag", function (e, dd) {
                        var actualMinWidth, d = Math.min(maxPageX, Math.max(minPageX, e.pageX)) - pageX, x;
                        if (d < 0) { // shrink column
                            x = d;
                            for (j = i; j >= 0; j--) {
                                c = columns[j];
                                if (c.resizable) {
                                    actualMinWidth = Math.max(c.minWidth || 0, absoluteColumnMinWidth);
                                    if (x && c.previousWidth + x < actualMinWidth) {
                                        x += c.previousWidth - actualMinWidth;
                                        c.width = actualMinWidth;
                                    } else {
                                        c.width = c.previousWidth + x;
                                        x = 0;
                                    }
                                }
                            }

                            if (options.forceFitColumns) {
                                x = -d;
                                for (j = i + 1; j < columnElements.length; j++) {
                                    c = columns[j];
                                    if (c.resizable) {
                                        if (x && c.maxWidth && (c.maxWidth - c.previousWidth < x)) {
                                            x -= c.maxWidth - c.previousWidth;
                                            c.width = c.maxWidth;
                                        } else {
                                            c.width = c.previousWidth + x;
                                            x = 0;
                                        }
                                    }
                                }
                            }
                        } else { // stretch column
                            x = d;
                            for (j = i; j >= 0; j--) {
                                c = columns[j];
                                if (c.resizable) {
                                    if (x && c.maxWidth && (c.maxWidth - c.previousWidth < x)) {
                                        x -= c.maxWidth - c.previousWidth;
                                        c.width = c.maxWidth;
                                    } else {
                                        c.width = c.previousWidth + x;
                                        x = 0;
                                    }
                                }
                            }

                            if (options.forceFitColumns) {
                                x = -d;
                                for (j = i + 1; j < columnElements.length; j++) {
                                    c = columns[j];
                                    if (c.resizable) {
                                        actualMinWidth = Math.max(c.minWidth || 0, absoluteColumnMinWidth);
                                        if (x && c.previousWidth + x < actualMinWidth) {
                                            x += c.previousWidth - actualMinWidth;
                                            c.width = actualMinWidth;
                                        } else {
                                            c.width = c.previousWidth + x;
                                            x = 0;
                                        }
                                    }
                                }
                            }
                        }
                        applyColumnHeaderWidths();
                        if (options.syncColumnCellResize) {
                            applyColumnWidths();
                        }
                    })
                    .bind("dragend", function (e, dd) {
                        var newWidth;
                        $(this).parent().removeClass("slick-header-column-active");
                        for (j = 0; j < columnElements.length; j++) {
                            c = columns[j];
                            newWidth = $(columnElements[j]).outerWidth();

                            if (c.previousWidth !== newWidth && c.rerenderOnResize) {
                                invalidateAllRows();
                            }
                        }
                        updateCanvasWidth(true);
                        render();
                        trigger(self.onColumnsResized, {grid: self});
                    });
            });
        }

        function getVBoxDelta($el) {
            var p = ["borderTopWidth", "borderBottomWidth", "paddingTop", "paddingBottom"];
            var delta = 0;
            $.each(p, function (n, val) {
                delta += parseFloat($el.css(val)) || 0;
            });
            return delta;
        }

        function measureCellPaddingAndBorder() {
            var el;
            var h = ["borderLeftWidth", "borderRightWidth", "paddingLeft", "paddingRight"];
            var v = ["borderTopWidth", "borderBottomWidth", "paddingTop", "paddingBottom"];

            // jquery prior to version 1.8 handles .width setter/getter as a direct css write/read
            // jquery 1.8 changed .width to read the true inner element width if box-sizing is set to border-box, and introduced a setter for .outerWidth
            // so for equivalent functionality, prior to 1.8 use .width, and after use .outerWidth
            var verArray = $.fn.jquery.split('.');
            jQueryNewWidthBehaviour = verArray[0] >= 1 && verArray[1] >= 8;

            el = $("<div class='ui-state-default slick-header-column' style='visibility:hidden'>-</div>").appendTo($headers);
            headerColumnWidthDiff = headerColumnHeightDiff = 0;
            if (el.css("box-sizing") != "border-box" && el.css("-moz-box-sizing") != "border-box" && el.css("-webkit-box-sizing") != "border-box") {
                $.each(h, function (n, val) {
                    headerColumnWidthDiff += parseFloat(el.css(val)) || 0;
                });
                $.each(v, function (n, val) {
                    headerColumnHeightDiff += parseFloat(el.css(val)) || 0;
                });
            }
            el.remove();

            var r = $("<div class='slick-row' />").appendTo($canvas);
            el = $("<div class='slick-cell' id='' style='visibility:hidden'>-</div>").appendTo(r);
            cellWidthDiff = cellHeightDiff = 0;
            if (el.css("box-sizing") != "border-box" && el.css("-moz-box-sizing") != "border-box" && el.css("-webkit-box-sizing") != "border-box") {
                $.each(h, function (n, val) {
                    cellWidthDiff += parseFloat(el.css(val)) || 0;
                });
                $.each(v, function (n, val) {
                    cellHeightDiff += parseFloat(el.css(val)) || 0;
                });
            }
            r.remove();

            absoluteColumnMinWidth = Math.max(headerColumnWidthDiff, cellWidthDiff);
        }

        function createCssRules() {
            $style = $("<style type='text/css' rel='stylesheet' />").appendTo($("head"));
            var rowHeight = (options.rowHeight - cellHeightDiff);
            var rules = [
                    "." + uid + " .slick-header-column { left: 1000px; }",
                    "." + uid + " .slick-top-panel { height:" + options.topPanelHeight + "px; }",
                    "." + uid + " .slick-headerrow-columns { height:" + options.headerRowHeight + "px; }",
                    "." + uid + " .slick-cell { height:" + rowHeight + "px; }",
                    "." + uid + " .slick-row { height:" + options.rowHeight + "px; }"
            ];

            for (var i = 0; i < columns.length; i++) {
                rules.push("." + uid + " .l" + i + " { }");
                rules.push("." + uid + " .r" + i + " { }");
            }

            if ($style[0].styleSheet) { // IE
                $style[0].styleSheet.cssText = rules.join(" ");
            } else {
                $style[0].appendChild(document.createTextNode(rules.join(" ")));
            }
        }

        function getColumnCssRules(idx) {
            if (!stylesheet) {
                var sheets = document.styleSheets;
                for (var i = 0; i < sheets.length; i++) {
                    if ((sheets[i].ownerNode || sheets[i].owningElement) == $style[0]) {
                        stylesheet = sheets[i];
                        break;
                    }
                }

                if (!stylesheet) {
                    throw new Error("Cannot find stylesheet.");
                }

                // find and cache column CSS rules
                columnCssRulesL = [];
                columnCssRulesR = [];
                var cssRules = (stylesheet.cssRules || stylesheet.rules);
                var matches, columnIdx;
                for (var i = 0; i < cssRules.length; i++) {
                    var selector = cssRules[i].selectorText;
                    if (matches = /\.l\d+/.exec(selector)) {
                        columnIdx = parseInt(matches[0].substr(2, matches[0].length - 2), 10);
                        columnCssRulesL[columnIdx] = cssRules[i];
                    } else if (matches = /\.r\d+/.exec(selector)) {
                        columnIdx = parseInt(matches[0].substr(2, matches[0].length - 2), 10);
                        columnCssRulesR[columnIdx] = cssRules[i];
                    }
                }
            }

            return {
                "left": columnCssRulesL[idx],
                "right": columnCssRulesR[idx]
            };
        }

        function removeCssRules() {
            $style.remove();
            stylesheet = null;
        }

        function destroy() {
            getEditorLock().cancelCurrentEdit();

            trigger(self.onBeforeDestroy, {grid: self});

            var i = plugins.length;
            while (i--) {
                unregisterPlugin(plugins[i]);
            }

            if (options.enableColumnReorder) {
                $headers.filter(":ui-sortable").sortable("destroy");
            }

            unbindAncestorScrollEvents();
            $container.unbind(".slickgrid");
            removeCssRules();

            $canvas.unbind("draginit dragstart dragend drag");
            if (options.enableCustomEvent) {
                $container.unbind(options.customEvents.join(' '));
            }
            $container.empty().removeClass(uid);
        }


        //////////////////////////////////////////////////////////////////////////////////////////////
        // General

        function trigger(evt, args, e) {
            e = e || new Slick.EventData();
            args = args || {};
            args.grid || (args.grid = self);
            return evt.notify(args, e, self);
        }

        function getEditorLock() {
            return options.editorLock;
        }

        function getEditController() {
            return editController;
        }

        function getColumnIndex(id) {
            return columnsById[id];
        }

        function autosizeColumns() {
            var i, c,
                widths = [],
                shrinkLeeway = 0,
                total = 0,
                prevTotal,
                availWidth = viewportHasVScroll ? viewportW - scrollbarDimensions.width : viewportW;

            for (i = 0; i < columns.length; i++) {
                c = columns[i];
                widths.push(c.width);
                total += c.width;
                if (c.resizable) {
                    shrinkLeeway += c.width - Math.max(c.minWidth, absoluteColumnMinWidth);
                }
            }

            // shrink
            prevTotal = total;
            while (total > availWidth && shrinkLeeway) {
                var shrinkProportion = (total - availWidth) / shrinkLeeway;
                for (i = 0; i < columns.length && total > availWidth; i++) {
                    c = columns[i];
                    var width = widths[i];
                    if (!c.resizable || width <= c.minWidth || width <= absoluteColumnMinWidth) {
                        continue;
                    }
                    var absMinWidth = Math.max(c.minWidth, absoluteColumnMinWidth);
                    var shrinkSize = Math.floor(shrinkProportion * (width - absMinWidth)) || 1;
                    shrinkSize = Math.min(shrinkSize, width - absMinWidth);
                    total -= shrinkSize;
                    shrinkLeeway -= shrinkSize;
                    widths[i] -= shrinkSize;
                }
                if (prevTotal <= total) {  // avoid infinite loop
                    break;
                }
                prevTotal = total;
            }

            // grow
            prevTotal = total;
            while (total < availWidth) {
                var growProportion = availWidth / total;
                for (i = 0; i < columns.length && total < availWidth; i++) {
                    c = columns[i];
                    var currentWidth = widths[i];
                    var growSize;

                    if (!c.resizable || c.maxWidth <= currentWidth) {
                        growSize = 0;
                    } else {
                        growSize = Math.min(Math.floor(growProportion * currentWidth) - currentWidth, (c.maxWidth - currentWidth) || 1000000) || 1;
                    }
                    total += growSize;
                    widths[i] += (total <= availWidth ? growSize : 0);
                }
                if (prevTotal >= total) {  // avoid infinite loop
                    break;
                }
                prevTotal = total;
            }

            var reRender = false;
            for (i = 0; i < columns.length; i++) {
                if (columns[i].rerenderOnResize && columns[i].width != widths[i]) {
                    reRender = true;
                }
                columns[i].width = widths[i];
            }

            applyColumnHeaderWidths();
            updateCanvasWidth(true);
            if (reRender) {
                invalidateAllRows();
                render();
            }
        }

        function applyColumnHeaderWidths() {
            if (!initialized) {
                return;
            }
            var h;
            for (var i = 0, headers = $headers.children(), ii = headers.length; i < ii; i++) {
                h = $(headers[i]);
                if (jQueryNewWidthBehaviour) {
                    if (h.outerWidth() !== columns[i].width) {
                        h.outerWidth(columns[i].width);
                    }
                } else {
                    if (h.width() !== columns[i].width - headerColumnWidthDiff) {
                        h.width(columns[i].width - headerColumnWidthDiff);
                    }
                }
            }

            updateColumnCaches();
        }

        function applyColumnWidths() {
            var x = 0, w, rule;
            for (var i = 0; i < columns.length; i++) {
                w = columns[i].width;

                rule = getColumnCssRules(i);
                rule.left.style.left = x + "px";
                rule.right.style.right = (canvasWidth - x - w) + "px";

                x += columns[i].width;
            }
        }

        function setSortColumn(columnId, ascending) {
            setSortColumns([
                { columnId: columnId, sortAsc: ascending}
            ]);
        }

        function setSortColumns(cols) {
            sortColumns = cols;

            var headerColumnEls = $headers.children();
            headerColumnEls
                .removeClass("slick-header-column-sorted")
                .find(".slick-sort-indicator")
                .removeClass("slick-sort-indicator-asc slick-sort-indicator-desc");

            $.each(sortColumns, function (i, col) {
                if (col.sortAsc == null) {
                    col.sortAsc = true;
                }
                var columnIndex = getColumnIndex(col.columnId);
                if (columnIndex != null) {
                    headerColumnEls.eq(columnIndex)
                        .addClass("slick-header-column-sorted")
                        .find(".slick-sort-indicator")
                        .addClass(col.sortAsc ? "slick-sort-indicator-asc" : "slick-sort-indicator-desc");
                }
            });
        }

        function getSortColumns() {
            return sortColumns;
        }

        function handleSelectedRangesChanged(e, ranges) {
            selectedRows = [];
            var hash = {};
            for (var i = 0; i < ranges.length; i++) {
                for (var j = ranges[i].fromRow; j <= ranges[i].toRow; j++) {
                    if (!hash[j]) {  // prevent duplicates
                        selectedRows.push(j);
                        hash[j] = {};
                    }
                    for (var k = ranges[i].fromCell; k <= ranges[i].toCell; k++) {
                        if (canCellBeSelected(j, k)) {
                            hash[j][columns[k].id] = options.selectedCellCssClass;
                        }
                    }
                }
            }

            setCellCssStyles(options.selectedCellCssClass, hash);

            trigger(self.onSelectedRowsChanged, {rows: getSelectedRows(), grid: self}, e);
        }

        function getColumns() {
            return columns;
        }

        function updateColumnCaches() {
            // Pre-calculate cell boundaries.
            columnPosLeft = [];
            columnPosRight = [];
            var x = 0;
            for (var i = 0, ii = columns.length; i < ii; i++) {
                columnPosLeft[i] = x;
                columnPosRight[i] = x + columns[i].width;
                x += columns[i].width;
            }
        }

        function setColumns(columnDefinitions) {
            columns = columnDefinitions;

            columnsById = {};
            for (var i = 0; i < columns.length; i++) {
                var m = columns[i] = $.extend({}, columnDefaults, columns[i]);
                columnsById[m.id] = i;
                if (m.minWidth && m.width < m.minWidth) {
                    m.width = m.minWidth;
                }
                if (m.maxWidth && m.width > m.maxWidth) {
                    m.width = m.maxWidth;
                }
            }

            updateColumnCaches();

            if (initialized) {
                invalidateAllRows();
                createColumnHeaders();
                removeCssRules();
                createCssRules();
                resizeCanvas();
                applyColumnWidths();
                handleScroll();
            }
        }

        function getOptions() {
            return options;
        }

        function setOptions(args) {
            if (!getEditorLock().commitCurrentEdit()) {
                return;
            }

            makeActiveCellNormal();

            if (options.enableAddRow !== args.enableAddRow) {
                invalidateRow(getDataLength());
            }

            options = $.extend(options, args);
            validateAndEnforceOptions();

            $viewport.css("overflow-y", options.autoHeight ? "hidden" : "auto");
            render();
        }

        function validateAndEnforceOptions() {
            if (options.autoHeight) {
                options.leaveSpaceForNewRows = false;
            }
        }

        function setData(newData, scrollToTop) {
            data = newData;
            invalidateAllRows();
            updateRowCount();
            if (scrollToTop) {
                scrollTo(0);
            }
        }

        function getData() {
            return data;
        }

        function getDataLength() {
            if (data.getLength) {
                return data.getLength();
            } else {
                return data.length;
            }
        }

        function getDataLengthIncludingAddNew() {
            return getDataLength() + (options.enableAddRow ? 1 : 0);
        }

        function getDataItem(i) {
            if (data.getItem) {
                return data.getItem(i);
            } else {
                return data[i];
            }
        }

        function getTopPanel() {
            return $topPanel[0];
        }

        function setTopPanelVisibility(visible) {
            if (options.showTopPanel != visible) {
                options.showTopPanel = visible;
                if (visible) {
                    $topPanelScroller.slideDown("fast", resizeCanvas);
                } else {
                    $topPanelScroller.slideUp("fast", resizeCanvas);
                }
            }
        }

        function setHeaderRowVisibility(visible) {
            if (options.showHeaderRow != visible) {
                options.showHeaderRow = visible;
                if (visible) {
                    $headerRowScroller.slideDown("fast", resizeCanvas);
                } else {
                    $headerRowScroller.slideUp("fast", resizeCanvas);
                }
            }
        }

        function getContainerNode() {
            return $container.get(0);
        }

        //////////////////////////////////////////////////////////////////////////////////////////////
        // Rendering / Scrolling

        function getRowTop(row) {
            return options.rowHeight * row - offset;
        }

        function getRowFromPosition(y) {
            return Math.floor((y + offset) / options.rowHeight);
        }

        function scrollTo(y) {
            y = Math.max(y, 0);
            y = Math.min(y, th - viewportH + (viewportHasHScroll ? scrollbarDimensions.height : 0));

            var oldOffset = offset;

            page = Math.min(n - 1, Math.floor(y / ph));
            offset = Math.round(page * cj);
            var newScrollTop = y - offset;

            if (offset != oldOffset) {
                var range = getVisibleRange(newScrollTop);
                cleanupRows(range);
                updateRowPositions();
            }

            if (prevScrollTop != newScrollTop) {
                vScrollDir = (prevScrollTop + oldOffset < newScrollTop + offset) ? 1 : -1;
                $viewport[0].scrollTop = (lastRenderedScrollTop = scrollTop = prevScrollTop = newScrollTop);

                trigger(self.onViewportChanged, {grid: self});
            }
        }

        function defaultFormatter(row, cell, value, columnDef, dataContext) {
            if (value == null) {
                return "";
            } else {
                return (value + "").replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
            }
        }

        function getFormatter(row, column) {
            var rowMetadata = data.getItemMetadata && data.getItemMetadata(row);

            // look up by id, then index
            var columnOverrides = rowMetadata &&
                rowMetadata.columns &&
                (rowMetadata.columns[column.id] || rowMetadata.columns[getColumnIndex(column.id)]);

            return (columnOverrides && columnOverrides.formatter) ||
                (rowMetadata && rowMetadata.formatter) ||
                column.formatter ||
                (options.formatterFactory && options.formatterFactory.getFormatter(column)) ||
                options.defaultFormatter;
        }

        function getEditor(row, cell) {
            var column = columns[cell];
            var rowMetadata = data.getItemMetadata && data.getItemMetadata(row);
            var columnMetadata = rowMetadata && rowMetadata.columns;

            if (columnMetadata && columnMetadata[column.id] && columnMetadata[column.id].editor !== undefined) {
                return columnMetadata[column.id].editor;
            }
            if (columnMetadata && columnMetadata[cell] && columnMetadata[cell].editor !== undefined) {
                return columnMetadata[cell].editor;
            }

            return column.editor || (options.editorFactory && options.editorFactory.getEditor(column));
        }

        function getDataItemValueForColumn(item, columnDef) {
            if (options.dataItemColumnValueExtractor) {
                return options.dataItemColumnValueExtractor(item, columnDef);
            }
            return item[columnDef.field];
        }

        function appendRowHtml(stringArray, row, range, dataLength) {
            var d = getDataItem(row);
            var dataLoading = row < dataLength && !d;
            var rowCss = "slick-row" +
                (dataLoading ? " loading" : "") +
                (row === activeRow ? " active" : "") +
                (row % 2 == 1 ? " odd" : " even");

            if (!d) {
                rowCss += " " + options.addNewRowCssClass;
            }

            var metadata = data.getItemMetadata && data.getItemMetadata(row);

            if (metadata && metadata.cssClasses) {
                rowCss += " " + metadata.cssClasses;
            }

            stringArray.push("<div class='ui-widget-content " + rowCss + "' style='top:" + getRowTop(row) + "px'>");

            var colspan, m;
            for (var i = 0, ii = columns.length; i < ii; i++) {
                m = columns[i];
                colspan = 1;
                if (metadata && metadata.columns) {
                    var columnData = metadata.columns[m.id] || metadata.columns[i];
                    colspan = (columnData && columnData.colspan) || 1;
                    if (colspan === "*") {
                        colspan = ii - i;
                    }
                }

                // Do not render cells outside of the viewport.
                if (columnPosRight[Math.min(ii - 1, i + colspan - 1)] > range.leftPx) {
                    if (columnPosLeft[i] > range.rightPx) {
                        // All columns to the right are outside the range.
                        break;
                    }

                    appendCellHtml(stringArray, row, i, colspan, d);
                }

                if (colspan > 1) {
                    i += (colspan - 1);
                }
            }

            stringArray.push("</div>");
        }

        function appendCellHtml(stringArray, row, cell, colspan, item) {
            // stringArray: stringBuilder containing the HTML parts
            // row, cell: row and column index
            // colspan: HTML colspan
            // item: grid data for row

            var m = columns[cell];
            var cellCss = "slick-cell l" + cell + " r" + Math.min(columns.length - 1, cell + colspan - 1) +
                (m.cssClass ? " " + m.cssClass : "");
            if (row === activeRow && cell === activeCell) {
                cellCss += (" active");
            }

            // TODO:  merge them together in the setter
            for (var key in cellCssClasses) {
                if (cellCssClasses[key][row] && cellCssClasses[key][row][m.id]) {
                    cellCss += (" " + cellCssClasses[key][row][m.id]);
                }
            }

            stringArray.push("<div class='" + cellCss + "'>");

            // if there is a corresponding row (if not, this is the Add New row or this data hasn't been loaded yet)
            if (item) {
                var value = getDataItemValueForColumn(item, m);
                stringArray.push(getFormatter(row, m)(row, cell, value, m, item));
            }

            stringArray.push("</div>");

            rowsCache[row].cellRenderQueue.push(cell);
            rowsCache[row].cellColSpans[cell] = colspan;
        }

        function cleanupRows(rangeToKeep) {
            for (var i in rowsCache) {
                if (((i = parseInt(i, 10)) !== activeRow) && (i < rangeToKeep.top || i > rangeToKeep.bottom)) {
                    removeRowFromCache(i);
                }
            }
            if (options.enableAsyncPostRenderCleanup) {
                startPostProcessingCleanup();
            }
        }

        function invalidate() {
            updateRowCount();
            invalidateAllRows();
            render();
        }

        function invalidateAllRows() {
            if (currentEditor) {
                makeActiveCellNormal();
            }
            for (var row in rowsCache) {
                removeRowFromCache(row);
            }
            if (options.enableAsyncPostRenderCleanup) {
                startPostProcessingCleanup();
            }
        }

        function queuePostProcessedRowForCleanup(cacheEntry, postProcessedRow, rowIdx) {
            postProcessgroupId++;

            // store and detach node for later async cleanup
            for (var columnIdx in postProcessedRow) {
                if (postProcessedRow.hasOwnProperty(columnIdx)) {
                    postProcessedCleanupQueue.push({
                        actionType: 'C',
                        groupId: postProcessgroupId,
                        node: cacheEntry.cellNodesByColumnIdx[ columnIdx | 0],
                        columnIdx: columnIdx | 0,
                        rowIdx: rowIdx
                    });
                }
            }
            postProcessedCleanupQueue.push({
                actionType: 'R',
                groupId: postProcessgroupId,
                node: cacheEntry.rowNode
            });
            $(cacheEntry.rowNode).detach();
        }

        function queuePostProcessedCellForCleanup(cellnode, columnIdx, rowIdx) {
            postProcessedCleanupQueue.push({
                actionType: 'C',
                groupId: postProcessgroupId,
                node: cellnode,
                columnIdx: columnIdx,
                rowIdx: rowIdx
            });
            $(cellnode).detach();
        }

        function removeRowFromCache(row) {
            var cacheEntry = rowsCache[row];
            if (!cacheEntry) {
                return;
            }

            if (rowNodeFromLastMouseWheelEvent === cacheEntry.rowNode) {
                cacheEntry.rowNode.style.display = 'none';
                zombieRowNodeFromLastMouseWheelEvent = rowNodeFromLastMouseWheelEvent;
                zombieRowCacheFromLastMouseWheelEvent = cacheEntry;
                zombieRowPostProcessedFromLastMouseWheelEvent = postProcessedRows[row];
                // ignore post processing cleanup in this case - it will be dealt with later
            } else {
                if (options.enableAsyncPostRenderCleanup && postProcessedRows[row]) {
                    queuePostProcessedRowForCleanup(cacheEntry, postProcessedRows[row], row);
                } else {
                    $canvas[0].removeChild(cacheEntry.rowNode);
                }
            }

            delete rowsCache[row];
            delete postProcessedRows[row];
            renderedRows--;
            counter_rows_removed++;
        }

        function invalidateRows(rows) {
            var i, rl;
            if (!rows || !rows.length) {
                return;
            }
            vScrollDir = 0;
            for (i = 0, rl = rows.length; i < rl; i++) {
                if (currentEditor && activeRow === rows[i]) {
                    makeActiveCellNormal();
                }
                if (rowsCache[rows[i]]) {
                    removeRowFromCache(rows[i]);
                }
            }
            if (options.enableAsyncPostRenderCleanup) {
                startPostProcessingCleanup();
            }

        }

        function invalidateRow(row) {
            invalidateRows([row]);
        }

        function updateCell(row, cell) {
            var cellNode = getCellNode(row, cell);
            if (!cellNode) {
                return;
            }

            var m = columns[cell], d = getDataItem(row);
            if (currentEditor && activeRow === row && activeCell === cell) {
                currentEditor.loadValue(d);
            } else {
                cellNode.innerHTML = d ? getFormatter(row, m)(row, cell, getDataItemValueForColumn(d, m), m, d) : "";
                invalidatePostProcessingResults(row);
            }
        }

        function updateRow(row) {
            var cacheEntry = rowsCache[row];
            if (!cacheEntry) {
                return;
            }

            ensureCellNodesInRowsCache(row);

            var d = getDataItem(row);

            for (var columnIdx in cacheEntry.cellNodesByColumnIdx) {
                if (!cacheEntry.cellNodesByColumnIdx.hasOwnProperty(columnIdx)) {
                    continue;
                }

                columnIdx = columnIdx | 0;
                var m = columns[columnIdx],
                    node = cacheEntry.cellNodesByColumnIdx[columnIdx];

                if (row === activeRow && columnIdx === activeCell && currentEditor) {
                    currentEditor.loadValue(d);
                } else if (d) {
                    node.innerHTML = getFormatter(row, m)(row, columnIdx, getDataItemValueForColumn(d, m), m, d);
                } else {
                    node.innerHTML = "";
                }
            }

            invalidatePostProcessingResults(row);
        }

        function getViewportHeight() {
            return parseFloat($.css($container[0], "height", true)) -
                parseFloat($.css($container[0], "paddingTop", true)) -
                parseFloat($.css($container[0], "paddingBottom", true)) -
                parseFloat($.css($headerScroller[0], "height")) - getVBoxDelta($headerScroller) -
                (options.showTopPanel ? options.topPanelHeight + getVBoxDelta($topPanelScroller) : 0) -
                (options.showHeaderRow ? options.headerRowHeight + getVBoxDelta($headerRowScroller) : 0);
        }

        function resizeCanvas() {
            if (!initialized) {
                return;
            }
            if (options.autoHeight) {
                viewportH = options.rowHeight * getDataLengthIncludingAddNew();
            } else {
                viewportH = getViewportHeight();
            }

            numVisibleRows = Math.ceil(viewportH / options.rowHeight);
            viewportW = parseFloat($.css($container[0], "width", true));
            if (!options.autoHeight) {
                $viewport.height(viewportH);
            }

            if (options.forceFitColumns) {
                autosizeColumns();
            }

            updateRowCount();
            handleScroll();
            // Since the width has changed, force the render() to reevaluate virtually rendered cells.
            lastRenderedScrollLeft = -1;
            render();
        }

        function getMinVisibleRows() {
            return Math.ceil(getViewportHeight() / options.rowHeight);
        }

        function updateRowCount() {
            if (!initialized) {
                return;
            }

            var dataLengthIncludingAddNew = getDataLengthIncludingAddNew();
            var numberOfRows = dataLengthIncludingAddNew +
                (options.leaveSpaceForNewRows ? numVisibleRows - 1 : 0);

            var oldViewportHasVScroll = viewportHasVScroll;
            // with autoHeight, we do not need to accommodate the vertical scroll bar
            viewportHasVScroll = !options.autoHeight && (numberOfRows * options.rowHeight > viewportH);

            makeActiveCellNormal();

            // remove the rows that are now outside of the data range
            // this helps avoid redundant calls to .removeRow() when the size of the data decreased by thousands of rows
            var l = dataLengthIncludingAddNew - 1;
            for (var i in rowsCache) {
                if (i >= l) {
                    removeRowFromCache(i);
                }
            }
            if (options.enableAsyncPostRenderCleanup) {
                startPostProcessingCleanup();
            }

            if (activeCellNode && activeRow > l) {
                resetActiveCell();
            }

            var oldH = h;
            th = Math.max(options.rowHeight * numberOfRows, viewportH - scrollbarDimensions.height);
            if (th < maxSupportedCssHeight) {
                // just one page
                h = ph = th;
                n = 1;
                cj = 0;
            } else {
                // break into pages
                h = maxSupportedCssHeight;
                ph = h / 100;
                n = Math.floor(th / ph);
                cj = (th - h) / (n - 1);
            }

            if (h !== oldH) {
                $canvas.css("height", h);
                scrollTop = $viewport[0].scrollTop;
            }

            var oldScrollTopInRange = (scrollTop + offset <= th - viewportH);

            if (th == 0 || scrollTop == 0) {
                page = offset = 0;
            } else if (oldScrollTopInRange) {
                // maintain virtual position
                scrollTo(scrollTop + offset);
            } else {
                // scroll to bottom
                scrollTo(th - viewportH);
            }

            if (h != oldH && options.autoHeight) {
                resizeCanvas();
            }

            if (options.forceFitColumns && oldViewportHasVScroll != viewportHasVScroll) {
                autosizeColumns();
            }
            updateCanvasWidth(false);
        }

        function getVisibleRange(viewportTop, viewportLeft) {
            if (viewportTop == null) {
                viewportTop = scrollTop;
            }
            if (viewportLeft == null) {
                viewportLeft = scrollLeft;
            }

            return {
                top: getRowFromPosition(viewportTop),
                bottom: getRowFromPosition(viewportTop + viewportH) + 1,
                leftPx: viewportLeft,
                rightPx: viewportLeft + viewportW
            };
        }

        function getRenderedRange(viewportTop, viewportLeft) {
            var range = getVisibleRange(viewportTop, viewportLeft);
            var buffer = Math.round(viewportH / options.rowHeight);
            var minBuffer = 3;

            if (vScrollDir == -1) {
                range.top -= buffer;
                range.bottom += minBuffer;
            } else if (vScrollDir == 1) {
                range.top -= minBuffer;
                range.bottom += buffer;
            } else {
                range.top -= minBuffer;
                range.bottom += minBuffer;
            }

            range.top = Math.max(0, range.top);
            range.bottom = Math.min(getDataLengthIncludingAddNew() - 1, range.bottom);

            range.leftPx -= viewportW;
            range.rightPx += viewportW;

            range.leftPx = Math.max(0, range.leftPx);
            range.rightPx = Math.min(canvasWidth, range.rightPx);

            return range;
        }

        function ensureCellNodesInRowsCache(row) {
            var cacheEntry = rowsCache[row];
            if (cacheEntry) {
                if (cacheEntry.cellRenderQueue.length) {
                    var lastChild = cacheEntry.rowNode.lastChild;
                    while (cacheEntry.cellRenderQueue.length) {
                        var columnIdx = cacheEntry.cellRenderQueue.pop();
                        cacheEntry.cellNodesByColumnIdx[columnIdx] = lastChild;
                        lastChild = lastChild.previousSibling;
                    }
                }
            }
        }

        function cleanUpCells(range, row) {
            var totalCellsRemoved = 0;
            var cacheEntry = rowsCache[row];

            // Remove cells outside the range.
            var cellsToRemove = [];
            for (var i in cacheEntry.cellNodesByColumnIdx) {
                // I really hate it when people mess with Array.prototype.
                if (!cacheEntry.cellNodesByColumnIdx.hasOwnProperty(i)) {
                    continue;
                }

                // This is a string, so it needs to be cast back to a number.
                i = i | 0;

                var colspan = cacheEntry.cellColSpans[i];
                if (columnPosLeft[i] > range.rightPx ||
                    columnPosRight[Math.min(columns.length - 1, i + colspan - 1)] < range.leftPx) {
                    if (!(row == activeRow && i == activeCell)) {
                        cellsToRemove.push(i);
                    }
                }
            }

            var cellToRemove, node;
            postProcessgroupId++;
            while ((cellToRemove = cellsToRemove.pop()) != null) {
                node = cacheEntry.cellNodesByColumnIdx[cellToRemove];
                if (options.enableAsyncPostRenderCleanup && postProcessedRows[row] && postProcessedRows[row][cellToRemove]) {
                    queuePostProcessedCellForCleanup(node, cellToRemove, row);
                } else {
                    cacheEntry.rowNode.removeChild(node);
                }

                delete cacheEntry.cellColSpans[cellToRemove];
                delete cacheEntry.cellNodesByColumnIdx[cellToRemove];
                if (postProcessedRows[row]) {
                    delete postProcessedRows[row][cellToRemove];
                }
                totalCellsRemoved++;
            }
        }

        function cleanUpAndRenderCells(range) {
            var cacheEntry;
            var stringArray = [];
            var processedRows = [];
            var cellsAdded;
            var totalCellsAdded = 0;
            var colspan;

            for (var row = range.top, btm = range.bottom; row <= btm; row++) {
                cacheEntry = rowsCache[row];
                if (!cacheEntry) {
                    continue;
                }

                // cellRenderQueue populated in renderRows() needs to be cleared first
                ensureCellNodesInRowsCache(row);

                cleanUpCells(range, row);

                // Render missing cells.
                cellsAdded = 0;

                var metadata = data.getItemMetadata && data.getItemMetadata(row);
                metadata = metadata && metadata.columns;

                var d = getDataItem(row);

                // TODO:  shorten this loop (index? heuristics? binary search?)
                for (var i = 0, ii = columns.length; i < ii; i++) {
                    // Cells to the right are outside the range.
                    if (columnPosLeft[i] > range.rightPx) {
                        break;
                    }

                    // Already rendered.
                    if ((colspan = cacheEntry.cellColSpans[i]) != null) {
                        i += (colspan > 1 ? colspan - 1 : 0);
                        continue;
                    }

                    colspan = 1;
                    if (metadata) {
                        var columnData = metadata[columns[i].id] || metadata[i];
                        colspan = (columnData && columnData.colspan) || 1;
                        if (colspan === "*") {
                            colspan = ii - i;
                        }
                    }

                    if (columnPosRight[Math.min(ii - 1, i + colspan - 1)] > range.leftPx) {
                        appendCellHtml(stringArray, row, i, colspan, d);
                        cellsAdded++;
                    }

                    i += (colspan > 1 ? colspan - 1 : 0);
                }

                if (cellsAdded) {
                    totalCellsAdded += cellsAdded;
                    processedRows.push(row);
                }
            }

            if (!stringArray.length) {
                return;
            }

            var x = document.createElement("div");
            x.innerHTML = stringArray.join("");

            var processedRow;
            var node;
            while ((processedRow = processedRows.pop()) != null) {
                cacheEntry = rowsCache[processedRow];
                var columnIdx;
                while ((columnIdx = cacheEntry.cellRenderQueue.pop()) != null) {
                    node = x.lastChild;
                    cacheEntry.rowNode.appendChild(node);
                    cacheEntry.cellNodesByColumnIdx[columnIdx] = node;
                }
            }
        }

        function renderRows(range) {
            var parentNode = $canvas[0],
                stringArray = [],
                rows = [],
                needToReselectCell = false,
                dataLength = getDataLength();

            for (var i = range.top, ii = range.bottom; i <= ii; i++) {
                if (rowsCache[i]) {
                    continue;
                }
                renderedRows++;
                rows.push(i);

                // Create an entry right away so that appendRowHtml() can
                // start populatating it.
                rowsCache[i] = {
                    "rowNode": null,

                    // ColSpans of rendered cells (by column idx).
                    // Can also be used for checking whether a cell has been rendered.
                    "cellColSpans": [],

                    // Cell nodes (by column idx).  Lazy-populated by ensureCellNodesInRowsCache().
                    "cellNodesByColumnIdx": [],

                    // Column indices of cell nodes that have been rendered, but not yet indexed in
                    // cellNodesByColumnIdx.  These are in the same order as cell nodes added at the
                    // end of the row.
                    "cellRenderQueue": []
                };

                appendRowHtml(stringArray, i, range, dataLength);
                if (activeCellNode && activeRow === i) {
                    needToReselectCell = true;
                }
                counter_rows_rendered++;
            }

            if (!rows.length) {
                return;
            }

            var x = document.createElement("div");
            x.innerHTML = stringArray.join("");

            for (var i = 0, ii = rows.length; i < ii; i++) {
                rowsCache[rows[i]].rowNode = parentNode.appendChild(x.firstChild);
            }

            if (needToReselectCell) {
                activeCellNode = getCellNode(activeRow, activeCell);
            }
        }

        function startPostProcessing() {
            if (!options.enableAsyncPostRender) {
                return;
            }
            clearTimeout(h_postrender);
            h_postrender = setTimeout(asyncPostProcessRows, options.asyncPostRenderDelay);
        }

        function startPostProcessingCleanup() {
            if (!options.enableAsyncPostRenderCleanup) {
                return;
            }
            clearTimeout(h_postrenderCleanup);
            h_postrenderCleanup = setTimeout(asyncPostProcessCleanupRows, options.asyncPostRenderCleanupDelay);
        }

        function invalidatePostProcessingResults(row) {
            // change status of columns to be re-rendered
            for (var columnIdx in postProcessedRows[row]) {
                if (postProcessedRows[row].hasOwnProperty(columnIdx)) {
                    postProcessedRows[row][columnIdx] = 'C';
                }
            }
            postProcessFromRow = Math.min(postProcessFromRow, row);
            postProcessToRow = Math.max(postProcessToRow, row);
            startPostProcessing();
        }

        function updateRowPositions() {
            for (var row in rowsCache) {
                rowsCache[row].rowNode.style.top = getRowTop(row) + "px";
            }
        }

        function render() {
            if (!initialized) {
                return;
            }
            var visible = getVisibleRange();
            var rendered = getRenderedRange();

            // remove rows no longer in the viewport
            cleanupRows(rendered);

            // add new rows & missing cells in existing rows
            if (lastRenderedScrollLeft != scrollLeft) {
                cleanUpAndRenderCells(rendered);
            }

            // render missing rows
            renderRows(rendered);

            postProcessFromRow = visible.top;
            postProcessToRow = Math.min(getDataLengthIncludingAddNew() - 1, visible.bottom);
            startPostProcessing();

            lastRenderedScrollTop = scrollTop;
            lastRenderedScrollLeft = scrollLeft;
            h_render = null;

            trigger(self.onRendered, {grid: this, lastRenderedScrollTop: scrollTop, lastRenderedScrollLeft: scrollLeft});
        }

        function handleHeaderRowScroll() {
            var scrollLeft = $headerRowScroller[0].scrollLeft;
            if (scrollLeft != $viewport[0].scrollLeft) {
                $viewport[0].scrollLeft = scrollLeft;
            }
        }

        function handleScroll() {
            scrollTop = $viewport[0].scrollTop;
            scrollLeft = $viewport[0].scrollLeft;
            var vScrollDist = Math.abs(scrollTop - prevScrollTop);
            var hScrollDist = Math.abs(scrollLeft - prevScrollLeft);

            if (hScrollDist) {
                prevScrollLeft = scrollLeft;
                $headerScroller[0].scrollLeft = scrollLeft;
                $topPanelScroller[0].scrollLeft = scrollLeft;
                $headerRowScroller[0].scrollLeft = scrollLeft;
            }

            if (vScrollDist) {
                vScrollDir = prevScrollTop < scrollTop ? 1 : -1;
                prevScrollTop = scrollTop;

                // switch virtual pages if needed
                if (vScrollDist < viewportH) {
                    scrollTo(scrollTop + offset);
                } else {
                    var oldOffset = offset;
                    if (h == viewportH) {
                        page = 0;
                    } else {
                        page = Math.min(n - 1, Math.floor(scrollTop * ((th - viewportH) / (h - viewportH)) * (1 / ph)));
                    }
                    offset = Math.round(page * cj);
                    if (oldOffset != offset) {
                        invalidateAllRows();
                    }
                }
            }

            if (hScrollDist || vScrollDist) {
                if (h_render) {
                    clearTimeout(h_render);
                }

                if (Math.abs(lastRenderedScrollTop - scrollTop) > 20 ||
                    Math.abs(lastRenderedScrollLeft - scrollLeft) > 20) {
                    if (options.forceSyncScrolling || (
                        Math.abs(lastRenderedScrollTop - scrollTop) < viewportH &&
                        Math.abs(lastRenderedScrollLeft - scrollLeft) < viewportW)) {
                        render();
                    } else {
                        h_render = setTimeout(render, 50);
                    }

                    trigger(self.onViewportChanged, {grid: self});
                }
            }

            trigger(self.onScroll, {scrollLeft: scrollLeft, scrollTop: scrollTop, grid: self});
        }

        function asyncPostProcessRows() {
            var dataLength = getDataLength();
            while (postProcessFromRow <= postProcessToRow) {
                var row = (vScrollDir >= 0) ? postProcessFromRow++ : postProcessToRow--;
                var cacheEntry = rowsCache[row];
                if (!cacheEntry || row >= dataLength) {
                    continue;
                }

                if (!postProcessedRows[row]) {
                    postProcessedRows[row] = {};
                }

                ensureCellNodesInRowsCache(row);
                for (var columnIdx in cacheEntry.cellNodesByColumnIdx) {
                    if (!cacheEntry.cellNodesByColumnIdx.hasOwnProperty(columnIdx)) {
                        continue;
                    }

                    columnIdx = columnIdx | 0;

                    var m = columns[columnIdx];
                    var processedStatus = postProcessedRows[row][columnIdx]; // C=cleanup and re-render, R=rendered
                    if (m.asyncPostRender && processedStatus !== 'R') {
                        var node = cacheEntry.cellNodesByColumnIdx[columnIdx];
                        if (node) {
                            m.asyncPostRender(node, row, getDataItem(row), m, (processedStatus === 'C'));
                        }
                        postProcessedRows[row][columnIdx] = 'R';
                    }
                }

                h_postrender = setTimeout(asyncPostProcessRows, options.asyncPostRenderDelay);
                return;
            }
        }

        function asyncPostProcessCleanupRows() {
            if (postProcessedCleanupQueue.length > 0) {
                var groupId = postProcessedCleanupQueue[0].groupId;

                // loop through all queue members with this groupID
                while (postProcessedCleanupQueue.length > 0 && postProcessedCleanupQueue[0].groupId == groupId) {
                    var entry = postProcessedCleanupQueue.shift();
                    if (entry.actionType == 'R') {
                        $(entry.node).remove();
                    }
                    if (entry.actionType == 'C') {
                        var column = columns[entry.columnIdx];
                        if (column.asyncPostRenderCleanup && entry.node) {
                            // cleanup must also remove element
                            column.asyncPostRenderCleanup(entry.node, entry.rowIdx, column);
                        }
                    }
                }

                // call this function again after the specified delay
                h_postrenderCleanup = setTimeout(asyncPostProcessCleanupRows, options.asyncPostRenderCleanupDelay);
            }
        }

        function updateCellCssStylesOnRenderedRows(addedHash, removedHash) {
            var node, columnId, addedRowHash, removedRowHash;
            for (var row in rowsCache) {
                removedRowHash = removedHash && removedHash[row];
                addedRowHash = addedHash && addedHash[row];

                if (removedRowHash) {
                    for (columnId in removedRowHash) {
                        if (!addedRowHash || removedRowHash[columnId] != addedRowHash[columnId]) {
                            node = getCellNode(row, getColumnIndex(columnId));
                            if (node) {
                                $(node).removeClass(removedRowHash[columnId]);
                            }
                        }
                    }
                }

                if (addedRowHash) {
                    for (columnId in addedRowHash) {
                        if (!removedRowHash || removedRowHash[columnId] != addedRowHash[columnId]) {
                            node = getCellNode(row, getColumnIndex(columnId));
                            if (node) {
                                $(node).addClass(addedRowHash[columnId]);
                            }
                        }
                    }
                }
            }
        }

        function addCellCssStyles(key, hash) {
            if (cellCssClasses[key]) {
                throw "addCellCssStyles: cell CSS hash with key '" + key + "' already exists.";
            }

            cellCssClasses[key] = hash;
            updateCellCssStylesOnRenderedRows(hash, null);

            trigger(self.onCellCssStylesChanged, { "key": key, "hash": hash, "grid": self });
        }

        function removeCellCssStyles(key) {
            if (!cellCssClasses[key]) {
                return;
            }

            updateCellCssStylesOnRenderedRows(null, cellCssClasses[key]);
            delete cellCssClasses[key];

            trigger(self.onCellCssStylesChanged, { "key": key, "hash": null, "grid": self });
        }

        function setCellCssStyles(key, hash) {
            var prevHash = cellCssClasses[key];

            cellCssClasses[key] = hash;
            updateCellCssStylesOnRenderedRows(hash, prevHash);

            trigger(self.onCellCssStylesChanged, { "key": key, "hash": hash, "grid": self });
        }

        function getCellCssStyles(key) {
            return cellCssClasses[key];
        }

        function flashCell(row, cell, speed) {
            speed = speed || 100;
            if (rowsCache[row]) {
                var $cell = $(getCellNode(row, cell));

                function toggleCellClass(times) {
                    if (!times) {
                        return;
                    }
                    setTimeout(function () {
                            $cell.queue(function () {
                                $cell.toggleClass(options.cellFlashingCssClass).dequeue();
                                toggleCellClass(times - 1);
                            });
                        },
                        speed);
                }

                toggleCellClass(4);
            }
        }

        //////////////////////////////////////////////////////////////////////////////////////////////
        // Interactivity

        function handleMouseWheel(e) {
            var rowNode = $(e.target).closest(".slick-row")[0];
            if (rowNode != rowNodeFromLastMouseWheelEvent) {
                if (zombieRowNodeFromLastMouseWheelEvent && zombieRowNodeFromLastMouseWheelEvent != rowNode) {
                    $canvas[0].removeChild(zombieRowNodeFromLastMouseWheelEvent);
                    if (options.enableAsyncPostRenderCleanup && zombieRowPostProcessedFromLastMouseWheelEvent) {
                        queuePostProcessedRowForCleanup(zombieRowCacheFromLastMouseWheelEvent,
                            zombieRowPostProcessedFromLastMouseWheelEvent);
                    } else {
                        $canvas[0].removeChild(zombieRowNodeFromLastMouseWheelEvent);
                    }
                    zombieRowNodeFromLastMouseWheelEvent = null;
                    zombieRowCacheFromLastMouseWheelEvent = null;
                    zombieRowPostProcessedFromLastMouseWheelEvent = null;

                    if (options.enableAsyncPostRenderCleanup) {
                        startPostProcessingCleanup();
                    }
                }
                rowNodeFromLastMouseWheelEvent = rowNode;
            }
        }

        function handleDragInit(e, dd) {
            var cell = getCellFromEvent(e);
            if (!cell || !cellExists(cell.row, cell.cell)) {
                return false;
            }

            var retval = trigger(self.onDragInit, dd, e);
            if (e.isImmediatePropagationStopped()) {
                return retval;
            }

            // if nobody claims to be handling drag'n'drop by stopping immediate propagation,
            // cancel out of it
            return false;
        }

        function handleDragStart(e, dd) {
            var cell = getCellFromEvent(e);
            if (!cell || !cellExists(cell.row, cell.cell)) {
                return false;
            }

            var retval = trigger(self.onDragStart, dd, e);
            if (e.isImmediatePropagationStopped()) {
                return retval;
            }

            return false;
        }

        function handleDrag(e, dd) {
            return trigger(self.onDrag, dd, e);
        }

        function handleDragEnd(e, dd) {
            trigger(self.onDragEnd, dd, e);
        }

        function handleKeyDown(e) {
            trigger(self.onKeyDown, {row: activeRow, cell: activeCell, grid: self}, e);
            var handled = e.isImmediatePropagationStopped();
            var keyCode = Slick.keyCode;

            if (!handled) {
                if (!e.shiftKey && !e.altKey && !e.ctrlKey) {
                    if (e.which == keyCode.ESCAPE) {
                        if (!getEditorLock().isActive()) {
                            return; // no editing mode to cancel, allow bubbling and default processing (exit without cancelling the event)
                        }
                        cancelEditAndSetFocus();
                    } else if (e.which == keyCode.PAGEDOWN) {
                        navigatePageDown(e);
                        handled = true;
                    } else if (e.which == keyCode.PAGEUP) {
                        navigatePageUp(e);
                        handled = true;
                    } else if (e.which == keyCode.LEFT) {
                        handled = navigateLeft(e);
                    } else if (e.which == keyCode.RIGHT) {
                        handled = navigateRight(e);
                    } else if (e.which == keyCode.UP) {
                        handled = navigateUp();
                    } else if (e.which == keyCode.DOWN) {
                        handled = navigateDown(e);
                    } else if (e.which == keyCode.TAB) {
                        handled = navigateNext(e);
                    } else if (e.which == keyCode.ENTER) {
                        if (options.editable) {
                            if (currentEditor) {
                                // adding new row
                                if (activeRow === getDataLength()) {
                                    navigateDown(e);
                                } else {
                                    commitEditAndSetFocus(e);
                                }
                            } else {
                                if (getEditorLock().commitCurrentEdit()) {
                                    makeActiveCellEditable(null, e);
                                }
                            }
                        }
                        handled = true;
                    }
                } else if (e.which == keyCode.TAB && e.shiftKey && !e.ctrlKey && !e.altKey) {
                    handled = navigatePrev(e);
                }
            }

            if (handled) {
                // the event has been handled so don't let parent element (bubbling/propagation) or browser (default) handle it
                e.stopPropagation();
                e.preventDefault();
                try {
                    e.originalEvent.keyCode = 0; // prevent default behaviour for special keys in IE browsers (F3, F5, etc.)
                }
                    // ignore exceptions - setting the original event's keycode throws access denied exception for "Ctrl"
                    // (hitting control key only, nothing else), "Shift" (maybe others)
                catch (error) {
                }
            }
        }

        function handleClick(e) {
            if (!currentEditor) {
                // if this click resulted in some cell child node getting focus,
                // don't steal it back - keyboard events will still bubble up
                // IE9+ seems to default DIVs to tabIndex=0 instead of -1, so check for cell clicks directly.
                if (e.target != document.activeElement || $(e.target).hasClass("slick-cell")) {
                    setFocus();
                }
            }

            var cell = getCellFromEvent(e);
            if (!cell || (currentEditor !== null && activeRow == cell.row && activeCell == cell.cell)) {
                return;
            }

            trigger(self.onClick, {row: cell.row, cell: cell.cell, grid: self}, e);
            if (e.isImmediatePropagationStopped()) {
                return;
            }

            if ((activeCell != cell.cell || activeRow != cell.row) && canCellBeActive(cell.row, cell.cell)) {
                if (!getEditorLock().isActive() || getEditorLock().commitCurrentEdit()) {
                    scrollRowIntoView(cell.row, false);
                    setActiveCellInternal(getCellNode(cell.row, cell.cell), null, e);
                }
            }
        }


        function outsideClickHandler(ev) {
            isOutsideEventFired = true;
            trigger(self.onOutsideGridClick, {grid: self, EditorLock: getEditorLock()}, ev);
        }

        function handleContextMenu(e) {
            var $cell = $(e.target).closest(".slick-cell", $canvas);
            if ($cell.length === 0) {
                return;
            }

            // are we editing this cell?
            if (activeCellNode === $cell[0] && currentEditor !== null) {
                return;
            }

            trigger(self.onContextMenu, {grid: self}, e);
        }

        function handleDblClick(e) {
            var cell = getCellFromEvent(e);
            if (!cell || (currentEditor !== null && activeRow == cell.row && activeCell == cell.cell)) {
                return;
            }

            trigger(self.onDblClick, {row: cell.row, cell: cell.cell, grid: self}, e);
            if (e.isImmediatePropagationStopped()) {
                return;
            }

            if (options.editable) {
                gotoCell(cell.row, cell.cell, true, e);
            }
        }

        function handleHeaderMouseEnter(e) {
            trigger(self.onHeaderMouseEnter, {
                "column": $(this).data("column"),
                "grid": self
            }, e);
        }

        function handleHeaderMouseLeave(e) {
            trigger(self.onHeaderMouseLeave, {
                "column": $(this).data("column"),
                "grid": self
            }, e);
        }

        function handleHeaderContextMenu(e) {
            var $header = $(e.target).closest(".slick-header-column", ".slick-header-columns");
            var column = $header && $header.data("column");
            trigger(self.onHeaderContextMenu, {column: column, grid: self}, e);
        }

        function handleHeaderClick(e) {
            var $header = $(e.target).closest(".slick-header-column", ".slick-header-columns");
            var column = $header && $header.data("column");
            if (column) {
                trigger(self.onHeaderClick, {column: column, grid: self}, e);
            }
        }

        function handleMouseEnter(e) {
            trigger(self.onMouseEnter, {grid: self}, e);
        }

        function handleMouseLeave(e) {
            trigger(self.onMouseLeave, {grid: self}, e);
        }

        function cellExists(row, cell) {
            return !(row < 0 || row >= getDataLength() || cell < 0 || cell >= columns.length);
        }

        function getCellFromPoint(x, y) {
            var row = getRowFromPosition(y);
            var cell = 0;

            var w = 0;
            for (var i = 0; i < columns.length && w < x; i++) {
                w += columns[i].width;
                cell++;
            }

            if (cell < 0) {
                cell = 0;
            }

            return {row: row, cell: cell - 1};
        }

        function getCellFromNode(cellNode) {
            // read column number from .l<columnNumber> CSS class
            var cls = /l\d+/.exec(cellNode.className);
            if (!cls) {
                throw "getCellFromNode: cannot get cell - " + cellNode.className;
            }
            return parseInt(cls[0].substr(1, cls[0].length - 1), 10);
        }

        function getRowFromNode(rowNode) {
            for (var row in rowsCache) {
                if (rowsCache[row].rowNode === rowNode) {
                    return row | 0;
                }
            }

            return null;
        }

        function getCellFromEvent(e) {
            var $cell = $(e.target).closest(".slick-cell", $canvas);
            if (!$cell.length) {
                return null;
            }

            var row = getRowFromNode($cell[0].parentNode);
            var cell = getCellFromNode($cell[0]);

            if (row == null || cell == null) {
                return null;
            } else {
                return {
                    "row": row,
                    "cell": cell
                };
            }
        }

        function getCellNodeBox(row, cell) {
            if (!cellExists(row, cell)) {
                return null;
            }

            var y1 = getRowTop(row);
            var y2 = y1 + options.rowHeight - 1;
            var x1 = 0;
            for (var i = 0; i < cell; i++) {
                x1 += columns[i].width;
            }
            var x2 = x1 + columns[cell].width;

            return {
                top: y1,
                left: x1,
                bottom: y2,
                right: x2
            };
        }

        //////////////////////////////////////////////////////////////////////////////////////////////
        // Cell switching

        function resetActiveCell() {
            setActiveCellInternal(null, false);
        }

        function setFocus() {
            if (tabbingDirection == -1) {
                $focusSink[0].focus();
            } else {
                $focusSink2[0].focus();
            }
        }

        function scrollCellIntoView(row, cell, doPaging) {
            scrollRowIntoView(row, doPaging);

            var colspan = getColspan(row, cell);
            var left = columnPosLeft[cell],
                right = columnPosRight[cell + (colspan > 1 ? colspan - 1 : 0)],
                scrollRight = scrollLeft + viewportW;

            if (left < scrollLeft) {
                $viewport.scrollLeft(left);
                handleScroll();
                render();
            } else if (right > scrollRight) {
                $viewport.scrollLeft(Math.min(left, right - $viewport[0].clientWidth));
                handleScroll();
                render();
            }
        }

        function setActiveCellInternal(newCell, opt_editMode, e) {
            if (activeCellNode !== null) {
                makeActiveCellNormal();
                $(activeCellNode).removeClass("active");
                if (rowsCache[activeRow]) {
                    $(rowsCache[activeRow].rowNode).removeClass("active");
                }
            }

            var activeCellChanged = (activeCellNode !== newCell);
            activeCellNode = newCell;

            if (activeCellNode != null) {
                activeRow = getRowFromNode(activeCellNode.parentNode);
                activeCell = activePosX = getCellFromNode(activeCellNode);

                if (opt_editMode == null) {
                    opt_editMode = (activeRow == getDataLength()) || options.autoEdit;
                }

                $(activeCellNode).addClass("active");
                $(rowsCache[activeRow].rowNode).addClass("active");

                if (options.editable && opt_editMode && isCellPotentiallyEditable(activeRow, activeCell)) {
                    clearTimeout(h_editorLoader);

                    if (options.asyncEditorLoading) {
                        h_editorLoader = setTimeout(function () {
                            makeActiveCellEditable(null, e);
                        }, options.asyncEditorLoadDelay);
                    } else {
                        makeActiveCellEditable(null, e);
                    }
                }
            } else {
                activeRow = activeCell = null;
            }

            if (activeCellChanged) {
                trigger(self.onActiveCellChanged, getActiveCell());
            }
        }

        function clearTextSelection() {
            if (document.selection && document.selection.empty) {
                try {
                    //IE fails here if selected element is not in dom
                    document.selection.empty();
                } catch (e) {
                }
            } else if (window.getSelection) {
                var sel = window.getSelection();
                if (sel && sel.removeAllRanges) {
                    sel.removeAllRanges();
                }
            }
        }

        function isCellPotentiallyEditable(row, cell) {
            var dataLength = getDataLength();
            // is the data for this row loaded?
            if (row < dataLength && !getDataItem(row)) {
                return false;
            }

            // are we in the Add New row?  can we create new from this cell?
            if (columns[cell].cannotTriggerInsert && row >= dataLength) {
                return false;
            }

            // does this cell have an editor?
            if (!getEditor(row, cell)) {
                return false;
            }

            return true;
        }

        function makeActiveCellNormal() {
            if (!currentEditor) {
                return;
            }
            trigger(self.onBeforeCellEditorDestroy, {editor: currentEditor, grid: self});
            currentEditor.destroy();
            currentEditor = null;

            if (activeCellNode) {
                var d = getDataItem(activeRow);
                $(activeCellNode).removeClass("editable invalid");
                if (d) {
                    var column = columns[activeCell];
                    var formatter = getFormatter(activeRow, column);
                    activeCellNode.innerHTML = formatter(activeRow, activeCell, getDataItemValueForColumn(d, column), column, d, self);
                    invalidatePostProcessingResults(activeRow);
                }
            }

            // if there previously was text selected on a page (such as selected text in the edit cell just removed),
            // IE can't set focus to anything else correctly
            if (navigator.userAgent.toLowerCase().match(/msie/)) {
                clearTextSelection();
            }

            getEditorLock().deactivate(editController);
        }

        function makeActiveCellEditable(editor, e) {
            if (!activeCellNode) {
                return;
            }
            if (!options.editable) {
                throw "Grid : makeActiveCellEditable : should never get called when options.editable is false";
            }

            // cancel pending async call if there is one
            clearTimeout(h_editorLoader);

            if (!isCellPotentiallyEditable(activeRow, activeCell)) {
                return;
            }

            var columnDef = columns[activeCell];
            var item = getDataItem(activeRow);

            if (trigger(self.onBeforeEditCell, {row: activeRow, cell: activeCell, item: item, column: columnDef, grid: self, ev: e}) === false) {
                setFocus();
                return;
            }

            getEditorLock().activate(editController);
            $(activeCellNode).addClass("editable");

            var useEditor = editor || getEditor(activeRow, activeCell);

            // don't clear the cell if a custom editor is passed through
            if (!editor && !columnDef.preventClearOnEdit) {
                activeCellNode.innerHTML = "";
            }

            currentEditor = new useEditor({
                grid: self,
                gridPosition: absBox($container[0]),
                position: absBox(activeCellNode),
                container: activeCellNode,
                column: columnDef,
                item: item || {},
                commitChanges: commitEditAndSetFocus,
                cancelChanges: cancelEditAndSetFocus
            }, e);

            e.stopPropagation(); //We have to prevent the propogation

            if (item) {
                currentEditor.loadValue(item);
            }

            serializedEditorValue = currentEditor.serializeValue();

            if (currentEditor.position) {
                handleActiveCellPositionChange();
            }
        }

        function commitEditAndSetFocus(e) {
            // if the commit fails, it would do so due to a validation error
            // if so, do not steal the focus from the editor
            if (getEditorLock().commitCurrentEdit()) {
                setFocus();
                if (options.autoEdit) {
                    navigateDown(e);
                }
            }
        }

        function cancelEditAndSetFocus() {
            if (getEditorLock().cancelCurrentEdit()) {
                setFocus();
            }
        }

        function absBox(elem) {
            var box = {
                top: elem.offsetTop,
                left: elem.offsetLeft,
                bottom: 0,
                right: 0,
                width: $(elem).outerWidth(),
                height: $(elem).outerHeight(),
                visible: true};
            box.bottom = box.top + box.height;
            box.right = box.left + box.width;

            // walk up the tree
            var offsetParent = elem.offsetParent;
            while ((elem = elem.parentNode) != document.body) {
                if (elem == null) break;

                if (box.visible && elem.scrollHeight != elem.offsetHeight && $(elem).css("overflowY") != "visible") {
                    box.visible = box.bottom > elem.scrollTop && box.top < elem.scrollTop + elem.clientHeight;
                }

                if (box.visible && elem.scrollWidth != elem.offsetWidth && $(elem).css("overflowX") != "visible") {
                    box.visible = box.right > elem.scrollLeft && box.left < elem.scrollLeft + elem.clientWidth;
                }

                box.left -= elem.scrollLeft;
                box.top -= elem.scrollTop;

                if (elem === offsetParent) {
                    box.left += elem.offsetLeft;
                    box.top += elem.offsetTop;
                    offsetParent = elem.offsetParent;
                }

                box.bottom = box.top + box.height;
                box.right = box.left + box.width;
            }

            return box;
        }

        function getActiveCellPosition() {
            return absBox(activeCellNode);
        }

        function getGridPosition() {
            return absBox($container[0])
        }

        function handleActiveCellPositionChange() {
            if (!activeCellNode) {
                return;
            }

            trigger(self.onActiveCellPositionChanged, {grid: self});

            if (currentEditor) {
                var cellBox = getActiveCellPosition();
                if (currentEditor.show && currentEditor.hide) {
                    if (!cellBox.visible) {
                        currentEditor.hide();
                    } else {
                        currentEditor.show();
                    }
                }

                if (currentEditor.position) {
                    currentEditor.position(cellBox);
                }
            }
        }

        function getCellEditor() {
            return currentEditor;
        }

        function getActiveCell() {
            if (!activeCellNode) {
                return null;
            } else {
                return {row: activeRow, cell: activeCell, grid: self};
            }
        }

        function getActiveCellNode() {
            return activeCellNode;
        }

        function scrollRowIntoView(row, doPaging) {
            var rowAtTop = row * options.rowHeight;
            var rowAtBottom = (row + 1) * options.rowHeight - viewportH + (viewportHasHScroll ? scrollbarDimensions.height : 0);

            // need to page down?
            if ((row + 1) * options.rowHeight > scrollTop + viewportH + offset) {
                scrollTo(doPaging ? rowAtTop : rowAtBottom);
                render();
            }
            // or page up?
            else if (row * options.rowHeight < scrollTop + offset) {
                scrollTo(doPaging ? rowAtBottom : rowAtTop);
                render();
            }
        }

        function scrollRowToTop(row) {
            scrollTo(row * options.rowHeight);
            render();
        }

        function scrollPage(dir) {
            var deltaRows = dir * numVisibleRows;
            scrollTo((getRowFromPosition(scrollTop) + deltaRows) * options.rowHeight);
            render();

            if (options.enableCellNavigation && activeRow != null) {
                var row = activeRow + deltaRows;
                var dataLengthIncludingAddNew = getDataLengthIncludingAddNew();
                if (row >= dataLengthIncludingAddNew) {
                    row = dataLengthIncludingAddNew - 1;
                }
                if (row < 0) {
                    row = 0;
                }

                var cell = 0, prevCell = null;
                var prevActivePosX = activePosX;
                while (cell <= activePosX) {
                    if (canCellBeActive(row, cell)) {
                        prevCell = cell;
                    }
                    cell += getColspan(row, cell);
                }

                if (prevCell !== null) {
                    setActiveCellInternal(getCellNode(row, prevCell));
                    activePosX = prevActivePosX;
                } else {
                    resetActiveCell();
                }
            }
        }

        function navigatePageDown() {
            scrollPage(1);
        }

        function navigatePageUp() {
            scrollPage(-1);
        }

        function getColspan(row, cell) {
            var metadata = data.getItemMetadata && data.getItemMetadata(row);
            if (!metadata || !metadata.columns) {
                return 1;
            }

            var columnData = metadata.columns[columns[cell].id] || metadata.columns[cell];
            var colspan = (columnData && columnData.colspan);
            if (colspan === "*") {
                colspan = columns.length - cell;
            } else {
                colspan = colspan || 1;
            }

            return colspan;
        }

        function findFirstFocusableCell(row) {
            var cell = 0;
            while (cell < columns.length) {
                if (canCellBeActive(row, cell)) {
                    return cell;
                }
                cell += getColspan(row, cell);
            }
            return null;
        }

        function findLastFocusableCell(row) {
            var cell = 0;
            var lastFocusableCell = null;
            while (cell < columns.length) {
                if (canCellBeActive(row, cell)) {
                    lastFocusableCell = cell;
                }
                cell += getColspan(row, cell);
            }
            return lastFocusableCell;
        }

        function gotoRight(row, cell, posX) {
            if (cell >= columns.length) {
                return null;
            }

            do {
                cell += getColspan(row, cell);
            }
            while (cell < columns.length && !canCellBeActive(row, cell));

            if (cell < columns.length) {
                return {
                    "row": row,
                    "cell": cell,
                    "posX": cell
                };
            }
            return null;
        }

        function gotoLeft(row, cell, posX) {
            if (cell <= 0) {
                return null;
            }

            var firstFocusableCell = findFirstFocusableCell(row);
            if (firstFocusableCell === null || firstFocusableCell >= cell) {
                return null;
            }

            var prev = {
                "row": row,
                "cell": firstFocusableCell,
                "posX": firstFocusableCell
            };
            var pos;
            while (true) {
                pos = gotoRight(prev.row, prev.cell, prev.posX);
                if (!pos) {
                    return null;
                }
                if (pos.cell >= cell) {
                    return prev;
                }
                prev = pos;
            }
        }

        function gotoDown(row, cell, posX) {
            var prevCell;
            var dataLengthIncludingAddNew = getDataLengthIncludingAddNew();
            while (true) {
                if (++row >= dataLengthIncludingAddNew) {
                    return null;
                }

                prevCell = cell = 0;
                while (cell <= posX) {
                    prevCell = cell;
                    cell += getColspan(row, cell);
                }

                if (canCellBeActive(row, prevCell)) {
                    return {
                        "row": row,
                        "cell": prevCell,
                        "posX": posX
                    };
                }
            }
        }

        function gotoUp(row, cell, posX) {
            var prevCell;
            while (true) {
                if (--row < 0) {
                    return null;
                }

                prevCell = cell = 0;
                while (cell <= posX) {
                    prevCell = cell;
                    cell += getColspan(row, cell);
                }

                if (canCellBeActive(row, prevCell)) {
                    return {
                        "row": row,
                        "cell": prevCell,
                        "posX": posX
                    };
                }
            }
        }

        function gotoNext(row, cell, posX) {
            if (row == null && cell == null) {
                row = cell = posX = 0;
                if (canCellBeActive(row, cell)) {
                    return {
                        "row": row,
                        "cell": cell,
                        "posX": cell
                    };
                }
            }

            var pos = gotoRight(row, cell, posX);
            if (pos) {
                return pos;
            }

            var firstFocusableCell = null;
            var dataLengthIncludingAddNew = getDataLengthIncludingAddNew();
            while (++row < dataLengthIncludingAddNew) {
                firstFocusableCell = findFirstFocusableCell(row);
                if (firstFocusableCell !== null) {
                    return {
                        "row": row,
                        "cell": firstFocusableCell,
                        "posX": firstFocusableCell
                    };
                }
            }
            return null;
        }

        function gotoPrev(row, cell, posX) {
            if (row == null && cell == null) {
                row = getDataLengthIncludingAddNew() - 1;
                cell = posX = columns.length - 1;
                if (canCellBeActive(row, cell)) {
                    return {
                        "row": row,
                        "cell": cell,
                        "posX": cell
                    };
                }
            }

            var pos;
            var lastSelectableCell;
            while (!pos) {
                pos = gotoLeft(row, cell, posX);
                if (pos) {
                    break;
                }
                if (--row < 0) {
                    return null;
                }

                cell = 0;
                lastSelectableCell = findLastFocusableCell(row);
                if (lastSelectableCell !== null) {
                    pos = {
                        "row": row,
                        "cell": lastSelectableCell,
                        "posX": lastSelectableCell
                    };
                }
            }
            return pos;
        }

        function navigateRight(e) {
            return navigate("right", e);
        }

        function navigateLeft(e) {
            return navigate("left", e);
        }

        function navigateDown(e) {
            return navigate("down", e);
        }

        function navigateUp(e) {
            return navigate("up", e);
        }

        function navigateNext(e) {
            return navigate("next", e);
        }

        function navigatePrev(e) {
            return navigate("prev", e);
        }

        /**
         * @param {string} dir Navigation direction.
         * @return {boolean} Whether navigation resulted in a change of active cell.
         */
        function navigate(dir, e) {
            if (!options.enableCellNavigation) {
                return false;
            }

            if (!activeCellNode && dir != "prev" && dir != "next") {
                return false;
            }

            if (!getEditorLock().commitCurrentEdit()) {
                return true;
            }
            setFocus();

            var tabbingDirections = {
                "up": -1,
                "down": 1,
                "left": -1,
                "right": 1,
                "prev": -1,
                "next": 1
            };
            tabbingDirection = tabbingDirections[dir];

            var stepFunctions = {
                "up": gotoUp,
                "down": gotoDown,
                "left": gotoLeft,
                "right": gotoRight,
                "prev": gotoPrev,
                "next": gotoNext
            };
            var stepFn = stepFunctions[dir];
            var pos = stepFn(activeRow, activeCell, activePosX);
            if (pos) {
                var isAddNewRow = (pos.row == getDataLength());
                scrollCellIntoView(pos.row, pos.cell, !isAddNewRow);
                setActiveCellInternal(getCellNode(pos.row, pos.cell), null, e);
                activePosX = pos.posX;
                return true;
            } else {
                setActiveCellInternal(getCellNode(activeRow, activeCell), null, e);
                return false;
            }
        }

        function getCellNode(row, cell) {
            if (rowsCache[row]) {
                ensureCellNodesInRowsCache(row);
                return rowsCache[row].cellNodesByColumnIdx[cell];
            }
            return null;
        }

        function setActiveCell(row, cell) {
            if (!initialized) {
                return;
            }
            if (row > getDataLength() || row < 0 || cell >= columns.length || cell < 0) {
                return;
            }

            if (!options.enableCellNavigation) {
                return;
            }

            scrollCellIntoView(row, cell, false);
            setActiveCellInternal(getCellNode(row, cell), false);
        }

        function canCellBeActive(row, cell) {
            if (!options.enableCellNavigation || row >= getDataLengthIncludingAddNew() ||
                row < 0 || cell >= columns.length || cell < 0) {
                return false;
            }

            var rowMetadata = data.getItemMetadata && data.getItemMetadata(row);
            if (rowMetadata && typeof rowMetadata.focusable === "boolean") {
                return rowMetadata.focusable;
            }

            var columnMetadata = rowMetadata && rowMetadata.columns;
            if (columnMetadata && columnMetadata[columns[cell].id] && typeof columnMetadata[columns[cell].id].focusable === "boolean") {
                return columnMetadata[columns[cell].id].focusable;
            }
            if (columnMetadata && columnMetadata[cell] && typeof columnMetadata[cell].focusable === "boolean") {
                return columnMetadata[cell].focusable;
            }

            return columns[cell].focusable;
        }

        function canCellBeSelected(row, cell) {
            if (row >= getDataLength() || row < 0 || cell >= columns.length || cell < 0) {
                return false;
            }

            var rowMetadata = data.getItemMetadata && data.getItemMetadata(row);
            if (rowMetadata && typeof rowMetadata.selectable === "boolean") {
                return rowMetadata.selectable;
            }

            var columnMetadata = rowMetadata && rowMetadata.columns && (rowMetadata.columns[columns[cell].id] || rowMetadata.columns[cell]);
            if (columnMetadata && typeof columnMetadata.selectable === "boolean") {
                return columnMetadata.selectable;
            }

            return columns[cell].selectable;
        }

        function gotoCell(row, cell, forceEdit, e) {
            if (!initialized) {
                return;
            }
            if (!canCellBeActive(row, cell)) {
                return;
            }

            if (!getEditorLock().commitCurrentEdit()) {
                return;
            }

            scrollCellIntoView(row, cell, false);

            var newCell = getCellNode(row, cell);

            // if selecting the 'add new' row, start editing right away
            setActiveCellInternal(newCell, forceEdit || (row === getDataLength()) || options.autoEdit, e);

            // if no editor was created, set the focus back on the grid
            if (!currentEditor) {
                setFocus();
            }
        }


        //////////////////////////////////////////////////////////////////////////////////////////////
        // IEditor implementation for the editor lock

        function commitCurrentEdit() {
            var item = getDataItem(activeRow);
            var column = columns[activeCell];
            if (currentEditor) {
                if (currentEditor.isValueChanged()) {
                    var validationResults = currentEditor.validate();

                    if (validationResults.valid) {
                        if (activeRow < getDataLength()) {
                            var editCommand = {
                                row: activeRow,
                                cell: activeCell,
                                editor: currentEditor,
                                serializedValue: currentEditor.serializeValue(),
                                prevSerializedValue: serializedEditorValue,
                                execute: function () {
                                    this.editor.applyValue(item, this.serializedValue);
                                    updateRow(this.row);
                                    trigger(self.onCellChange, {
                                        row: activeRow,
                                        cell: activeCell,
                                        item: item,
                                        grid: self
                                    });
                                },
                                undo: function () {
                                    this.editor.applyValue(item, this.prevSerializedValue);
                                    updateRow(this.row);
                                    trigger(self.onCellChange, {
                                        row: activeRow,
                                        cell: activeCell,
                                        item: item,
                                        grid: self
                                    });
                                }
                            };

                            if (options.editCommandHandler) {
                                makeActiveCellNormal();
                                options.editCommandHandler(item, column, editCommand);
                            } else {
                                editCommand.execute();
                                makeActiveCellNormal();
                            }

                        } else {
                            var newItem = {};
                            currentEditor.applyValue(newItem, currentEditor.serializeValue());
                            makeActiveCellNormal();
                            trigger(self.onAddNewRow, {item: newItem, column: column, grid: self});
                        }

                        // check whether the lock has been re-acquired by event handlers
                        return !getEditorLock().isActive();
                    } else {
                        // Re-add the CSS class to trigger transitions, if any.
                        $(activeCellNode).removeClass("invalid");
                        $(activeCellNode).width();  // force layout
                        $(activeCellNode).addClass("invalid");

                        trigger(self.onValidationError, {
                            editor: currentEditor,
                            cellNode: activeCellNode,
                            validationResults: validationResults,
                            row: activeRow,
                            cell: activeCell,
                            column: column,
                            grid: self,
                            isOutsideClicked: isOutsideEventFired,
                            EditorLock: getEditorLock()
                        });

                        if(getEditorLock().isActive()) {
                            currentEditor.focus();
                        }

                        return false;
                    }
                }

                makeActiveCellNormal();
            }
            return true;
        }

        function cancelCurrentEdit() {
            makeActiveCellNormal();
            return true;
        }

        function rowsToRanges(rows) {
            var ranges = [];
            var lastCell = columns.length - 1;
            for (var i = 0; i < rows.length; i++) {
                ranges.push(new Slick.Range(rows[i], 0, rows[i], lastCell));
            }
            return ranges;
        }

        function getSelectedRows() {
            if (!selectionModel) {
                throw "Selection model is not set";
            }
            return selectedRows;
        }

        function setSelectedRows(rows) {
            if (!selectionModel) {
                throw "Selection model is not set";
            }
            selectionModel.setSelectedRanges(rowsToRanges(rows));
        }

        function isInitialized() {
            return initialized;
        }

        //////////////////////////////////////////////////////////////////////////////////////////////
        // Debug

        this.debug = function () {
            var s = "";

            s += ("\n" + "counter_rows_rendered:  " + counter_rows_rendered);
            s += ("\n" + "counter_rows_removed:  " + counter_rows_removed);
            s += ("\n" + "renderedRows:  " + renderedRows);
            s += ("\n" + "numVisibleRows:  " + numVisibleRows);
            s += ("\n" + "maxSupportedCssHeight:  " + maxSupportedCssHeight);
            s += ("\n" + "n(umber of pages):  " + n);
            s += ("\n" + "(current) page:  " + page);
            s += ("\n" + "page height (ph):  " + ph);
            s += ("\n" + "vScrollDir:  " + vScrollDir);

            alert(s);
        };

        // a debug helper to be able to access private members
        this.eval = function (expr) {
            return eval(expr);
        };

        //////////////////////////////////////////////////////////////////////////////////////////////
        // Public API

        $.extend(this, {
            "getVersion": "2.3.0",

            // Events
            "onScroll": new Slick.Event(),
            "onSort": new Slick.Event(),
            "onHeaderMouseEnter": new Slick.Event(),
            "onHeaderMouseLeave": new Slick.Event(),
            "onHeaderContextMenu": new Slick.Event(),
            "onHeaderClick": new Slick.Event(),
            "onHeaderCellRendered": new Slick.Event(),
            "onBeforeHeaderCellDestroy": new Slick.Event(),
            "onHeaderRowCellRendered": new Slick.Event(),
            "onBeforeHeaderRowCellDestroy": new Slick.Event(),
            "onMouseEnter": new Slick.Event(),
            "onMouseLeave": new Slick.Event(),
            "onClick": new Slick.Event(),
            "onDblClick": new Slick.Event(),
            "onContextMenu": new Slick.Event(),
            "onKeyDown": new Slick.Event(),
            "onAddNewRow": new Slick.Event(),
            "onValidationError": new Slick.Event(),
            "onViewportChanged": new Slick.Event(),
            "onColumnsReordered": new Slick.Event(),
            "onColumnsResized": new Slick.Event(),
            "onCellChange": new Slick.Event(),
            "onBeforeEditCell": new Slick.Event(),
            "onBeforeCellEditorDestroy": new Slick.Event(),
            "onBeforeDestroy": new Slick.Event(),
            "onActiveCellChanged": new Slick.Event(),
            "onActiveCellPositionChanged": new Slick.Event(),
            "onDragInit": new Slick.Event(),
            "onDragStart": new Slick.Event(),
            "onDrag": new Slick.Event(),
            "onDragEnd": new Slick.Event(),
            "onSelectedRowsChanged": new Slick.Event(),
            "onCellCssStylesChanged": new Slick.Event(),
            "onInitialize": new Slick.Event(),
            "onRendered": new Slick.Event(),
            "onOutsideGridClick": new Slick.Event(),
            // Methods
            "registerPlugin": registerPlugin,
            "unregisterPlugin": unregisterPlugin,
            "getColumns": getColumns,
            "setColumns": setColumns,
            "getColumnIndex": getColumnIndex,
            "updateColumnHeader": updateColumnHeader,
            "setSortColumn": setSortColumn,
            "setSortColumns": setSortColumns,
            "getSortColumns": getSortColumns,
            "autosizeColumns": autosizeColumns,
            "getOptions": getOptions,
            "setOptions": setOptions,
            "getData": getData,
            "getDataLength": getDataLength,
            "getDataItem": getDataItem,
            "setData": setData,
            "getSelectionModel": getSelectionModel,
            "setSelectionModel": setSelectionModel,
            "getSelectedRows": getSelectedRows,
            "setSelectedRows": setSelectedRows,
            "getContainerNode": getContainerNode,

            "render": render,
            "invalidate": invalidate,
            "invalidateRow": invalidateRow,
            "invalidateRows": invalidateRows,
            "invalidateAllRows": invalidateAllRows,
            "updateCell": updateCell,
            "updateRow": updateRow,
            "getViewport": getVisibleRange,
            "getRenderedRange": getRenderedRange,
            "resizeCanvas": resizeCanvas,
            "updateRowCount": updateRowCount,
            "scrollRowIntoView": scrollRowIntoView,
            "scrollRowToTop": scrollRowToTop,
            "scrollCellIntoView": scrollCellIntoView,
            "getCanvasNode": getCanvasNode,
            "focus": setFocus,

            "getCellFromPoint": getCellFromPoint,
            "getCellFromEvent": getCellFromEvent,
            "getActiveCell": getActiveCell,
            "setActiveCell": setActiveCell,
            "getActiveCellNode": getActiveCellNode,
            "getActiveCellPosition": getActiveCellPosition,
            "resetActiveCell": resetActiveCell,
            "editActiveCell": makeActiveCellEditable,
            "getCellEditor": getCellEditor,
            "getCellNode": getCellNode,
            "getCellNodeBox": getCellNodeBox,
            "canCellBeSelected": canCellBeSelected,
            "canCellBeActive": canCellBeActive,
            "navigatePrev": navigatePrev,
            "navigateNext": navigateNext,
            "navigateUp": navigateUp,
            "navigateDown": navigateDown,
            "navigateLeft": navigateLeft,
            "navigateRight": navigateRight,
            "navigatePageUp": navigatePageUp,
            "navigatePageDown": navigatePageDown,
            "gotoCell": gotoCell,
            "getTopPanel": getTopPanel,
            "setTopPanelVisibility": setTopPanelVisibility,
            "setHeaderRowVisibility": setHeaderRowVisibility,
            "getHeaderRow": getHeaderRow,
            "getHeaderRowColumn": getHeaderRowColumn,
            "getGridPosition": getGridPosition,
            "flashCell": flashCell,
            "addCellCssStyles": addCellCssStyles,
            "setCellCssStyles": setCellCssStyles,
            "removeCellCssStyles": removeCellCssStyles,
            "getCellCssStyles": getCellCssStyles,

            "init": finishInitialization,
            "destroy": destroy,

            // IEditor implementation
            "getEditorLock": getEditorLock,
            "getEditController": getEditController,


            //Few additional methods exposed
            "getHeaderWidth": getHeadersWidth,
            "getCanvasWidth": getCanvasWidth,
            "getViewportHeight": getViewportHeight,
            "getUID": getUID,
            "isInitialized": isInitialized
        });

        init();
    }

}(jQuery));