Feature/form dataprovider

CHANGES.txt

@@ -7,6 +7,8 @@ Improvements
 - Added optional timezone parameter to Form initialisation.
 
 New feature
+- Added FormDataprovider. A Formdataprovider can be used to fill the form with
+  (dynamic) values and options.
 - Added datetime picker widget. See https://github.com/Eonasdan/bootstrap-datetimepicker
 - Added currency widget.
 - Added new "fields" command to generate.py command (in contrib) to export the
@@ -28,7 +30,6 @@ Bugfix:
 Internal release only already includes most of the features from 1.1.0 but
 never has been released in the public.
 
-
 1.0.2
 =====
 Maintenance release.

formbar/fields.py

@@ -759,6 +759,9 @@ def get_options(self):
         elif isinstance(user_defined_options, str):
             for option in self._form.merged_data.get(user_defined_options):
                 options.append((option[0], option[1], True))
+        elif self._form._item and hasattr(self._form._item, "get_options"):
+            for option in self._form._item.get_options(self.name):
+                options.append((option[0], option[1], True))
         return self.sort_options(options)
 
     def _from_python(self, value):

formbar/form.py

@@ -74,6 +74,42 @@ class ValidationException(Exception):
     pass
 
 
+class FormDataprovider(object):
+    """Dummy class which can be used to provided dynamic data to the
+    form. It can be provided as item on the form init to provide
+    dynamically loaded options and values.
+
+    As said the dataprovider can be user to provide `options` and `values`.
+    Both are provided by defining propertys.
+
+    1. Value
+    The function should simply return the pythonic value of the field:
+
+        @property
+        def foo(self):
+            return "1"
+
+    1. Options
+    The function should return a list of tuples. The first value of the
+    tuple is the displayed label and the second value is the value of
+    the option:
+
+        @property
+        def foo_options(self):
+            return [("Foo", "1"), ("Bar", "2")]
+
+    or you can use the helper method `get_options(fieldname)`
+    """
+
+    def __init__(self, ctx):
+        self.ctx = ctx
+        """Can be anything. E.g db connection, request. It depends on the context."""
+
+    def get_options(self, name):
+        if hasattr(self, name+"_options"):
+            return getattr(self, name+"_options")
+        return []
+
 class Validator(object):
     """Validator class for external validators. External validators can
     be used to implement more complicated validations on the converted