Fixed improper menu disposal, leading to segfaults under certain circ…

…umstances.

This is implemented in the wx backend, but was inexplicably missing here.

enthought/pyface/ui/qt4/action/action_item.py

@@ -65,6 +65,7 @@ def __init__(self, parent, menu, item, controller):
         else:
             self.control = menu.addAction(action.image.create_icon(),
                     action.name, self._qt4_on_triggered, action.accelerator)
+        menu.menu_items.append(self)
 
         self.control.setToolTip(action.tooltip)
         self.control.setWhatsThis(action.description)
@@ -103,6 +104,17 @@ def __init__(self, parent, menu, item, controller):
             self.controller = controller
             controller.add_to_menu(self)
 
+    def dispose(self):
+        action = self.item.action
+        action.on_trait_change(self._on_action_enabled_changed, 'enabled',
+            remove=True)
+        action.on_trait_change(self._on_action_visible_changed, 'visible',
+            remove=True)
+        action.on_trait_change(self._on_action_checked_changed, 'checked',
+            remove=True)
+        action.on_trait_change(self._on_action_name_changed, 'name',
+            remove=True)
+
     ###########################################################################
     # Private interface.
     ###########################################################################

enthought/pyface/ui/qt4/action/menu_manager.py

@@ -91,6 +91,9 @@ def __init__(self, manager, parent, controller):
         # The controller.
         self._controller = controller
 
+        # List of menu items
+        self.menu_items = []
+
         # Create the menu structure.
         self.refresh()
 
@@ -104,6 +107,16 @@ def __init__(self, manager, parent, controller):
     # '_Menu' interface.
     ###########################################################################
 
+    def clear(self):
+        """ Clears the items from the menu. """
+
+        for item in self.menu_items:
+            item.dispose()
+
+        self.menu_items = []
+
+        super(_Menu, self).clear()
+
     def is_empty(self):
         """ Is the menu empty? """