HorizontalSliderWithBrowser: slider with play button

src/silx/gui/widgets/FrameBrowser.py

@@ -21,6 +21,7 @@
 # THE SOFTWARE.
 #
 # ###########################################################################*/
+from __future__ import annotations
 """This module defines two main classes:
 
     - :class:`FrameBrowser`: a widget with 4 buttons (first, previous, next,
@@ -218,6 +219,70 @@ def setValue(self, value):
         self._textChangedSlot()
 
 
+class _SliderPlayWidgetAction(qt.QWidgetAction):
+
+    sigValueChanged = qt.Signal(int)
+
+    def __init__(
+            self,
+            parent: qt.QWidget | None = None,
+            label: str | None = None,
+            tooltip: str | None = None,
+    ):
+        super().__init__(parent)
+        self._build(label=label, tooltip=tooltip)
+
+    def _build(self, label: str, tooltip: str):
+        widget = qt.QWidget()
+        layout = qt.QHBoxLayout()
+        widget.setLayout(layout)
+        self._spinbox = qt.QSpinBox()
+        self._spinbox.setToolTip(tooltip)
+        self._spinbox.setRange(1,1000000)
+        self._spinbox.valueChanged.connect(self.sigValueChanged)
+        label = qt.QLabel(label)
+        label.setToolTip(tooltip)
+        layout.addWidget(label)
+        layout.addWidget(self._spinbox)
+        self.setDefaultWidget(widget)
+
+    def value(self) -> int:
+        return self._spinbox.value()
+
+    def setValue(self, value: int):
+        self._spinbox.setValue(value)
+
+
+class _PlayButtonContextMenu(qt.QMenu):
+
+    sigFrameRateChanged = qt.Signal(int)
+
+    def __init__(self, parent: qt.QWidget | None = None):
+        super().__init__(parent)
+        self._build()
+
+    def _build(self):
+        self._framerateAction = _SliderPlayWidgetAction(self, label="FPS:", tooltip="Display speed in frames per second")
+        self._framerateAction.sigValueChanged.connect(self.sigFrameRateChanged)
+        self._stepAction = _SliderPlayWidgetAction(self, label="Step:", tooltip="Step between displayed frames")
+        self.addAction(self._framerateAction)
+        self._framerateAction.setValue(10)
+        self.addAction(self._stepAction)
+        self._stepAction.setValue(1)
+
+    def getFrameRate(self) -> int:
+        return self._framerateAction.value()
+
+    def setFrameRate(self, rate: int):
+        self._framerateAction.setValue(rate)
+
+    def getStep(self) -> int:
+        return self._stepAction.value()
+
+    def setStep(self, interval: int):
+        self._stepAction.setValue(interval)
+
+
 class HorizontalSliderWithBrowser(qt.QAbstractSlider):
     """
     Slider widget combining a :class:`QSlider` and a :class:`FrameBrowser`.
@@ -254,6 +319,27 @@ def __init__(self, parent=None):
         self._slider.valueChanged[int].connect(self._sliderSlot)
         self._browser.sigIndexChanged.connect(self._browserSlot)
 
+        fontMetric = self.fontMetrics()
+        iconSize = qt.QSize(fontMetric.height(), fontMetric.height())
+
+        self.__timer = qt.QTimer(self)
+        self.__timer.timeout.connect(self._updateState)
+
+        self._playButton = qt.QToolButton(self)
+        self._playButton.setToolTip("Display dataset movie.")
+        self._playButton.setIcon(icons.getQIcon("camera"))
+        self._playButton.setIconSize(iconSize)
+        self._playButton.setCheckable(True)
+        self.mainLayout.addWidget(self._playButton)
+
+        self._playButton.toggled.connect(self._playButtonToggled)
+        self._menuPlaySlider = _PlayButtonContextMenu(self)
+        self._menuPlaySlider.sigFrameRateChanged.connect(self._frameRateChanged)
+        self._frameRateChanged(self.getFrameRate())
+        self._playButton.setMenu(self._menuPlaySlider)
+        self._playButton.setPopupMode(qt.QToolButton.MenuButtonPopup)
+
+
     def lineEdit(self):
         """Returns the line edit provided by this widget.
 
@@ -312,3 +398,38 @@ def setValue(self, value):
     def value(self):
         """Get selected value"""
         return self._slider.value()
+
+    def setFrameRate(self, value: int):
+        """Set the frame rate at which images are displayed"""
+        self._menuPlaySlider.setFrameRate(value)
+
+    def getFrameRate(self) -> int:
+        """Get the frame rate at which images are displayed"""
+        return self._menuPlaySlider.getFrameRate()
+
+    def setPlayImageStep(self, value: int):
+        """Set the step between displayed images when playing"""
+        self._menuPlaySlider.setStep(value)
+
+    def getPlayImageStep(self) -> int:
+        """Returns the step between displayed images"""
+        return self._menuPlaySlider.getStep()
+
+    def _frameRateChanged(self, framerate: int):
+        """Update the timer interval"""
+        self.__timer.setInterval(int(1 / framerate * 1e3))
+
+    def _playButtonToggled(self, checked: bool):
+        """Start/Stop the slider sequence."""
+        if checked:
+            self.__timer.start()
+            return
+        self.__timer.stop()
+
+    def _updateState(self):
+        """Advance an interval number of frames in the browser sequence."""
+        currentIndex = self._browser.getValue()
+        if currentIndex < self._browser.getRange()[-1]:
+            self.setValue(currentIndex + self.getPlayImageStep())
+        else:
+            self._playButton.setChecked(False)