Merge pull request #3890 from vallsv/added-backend-signal

PlotWidget: Added sigBackendChanged
silx-kit · Jul 10, 2023 · 577d260 · 577d260
2 parents b64664a + bbe5a47
commit 577d260
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Showing 2 changed files with 7 additions and 12 deletions.
diff --git a/src/silx/gui/plot/PlotWidget.py b/src/silx/gui/plot/PlotWidget.py
@@ -360,6 +360,9 @@ class PlotWidget(qt.QMainWindow):
     It provides the menu which will be displayed.
     """
 
+    sigBackendChanged = qt.Signal()
+    """Signal emitted when the backend have changed."""
+
     def __init__(self, parent=None, backend=None):
         self._autoreplot = False
         self._dirty = False
@@ -623,6 +626,8 @@ def setBackend(self, backend):
         for item in self.getItems():
             item._updated()
 
+        self.sigBackendChanged.emit()
+
     def getBackend(self):
         """Returns the backend currently used by :class:`PlotWidget`.
 

diff --git a/src/silx/gui/plot/actions/control.py b/src/silx/gui/plot/actions/control.py
@@ -639,7 +639,6 @@ def __init__(self, plot, parent=None):
         }
 
         name = self._getBackendName(plot)
-        self.__state = name
         icon, tooltip = self._states[name]
         super(OpenGLAction, self).__init__(
             plot,
@@ -649,10 +648,10 @@ def __init__(self, plot, parent=None):
             triggered=self._actionTriggered,
             checkable=True,
             parent=parent)
+        plot.sigBackendChanged.connect(self._backendUpdated)
 
     def _backendUpdated(self):
         name = self._getBackendName(self.plot)
-        self.__state = name
         icon, tooltip = self._states[name]
         self.setIcon(icon)
         self.setToolTip(tooltip)
@@ -671,21 +670,12 @@ def _getBackendName(self, plot):
     def _actionTriggered(self, checked=False):
         plot = self.plot
         name = self._getBackendName(self.plot)
-        if self.__state != name:
-            # THere is no event to know the backend was updated
-            # So here we check if there is a mismatch between the displayed state
-            # and the real state of the widget
-            self._backendUpdated()
-            return
         if name != "opengl":
             from silx.gui.utils import glutils
             result = glutils.isOpenGLAvailable()
             if not result:
-                qt.QMessageBox.critical(plot, "OpenGL rendering not available", result.error)
-                # Uncheck if needed
-                self._backendUpdated()
+                qt.QMessageBox.critical(plot, "OpenGL rendering is not available", result.error)
                 return
             plot.setBackend("opengl")
         else:
             plot.setBackend("matplotlib")
-        self._backendUpdated()