+ self.parent = parent
+ self.onShow.append(self.addWatcher)
+ self.onHide.append(self.removeWatcher)
+
+ def addWatcher(self):
+ self.parent["menu"].onSelectionChanged.append(self.selectionChanged)
+ self.selectionChanged()
+
+ def removeWatcher(self):
+ self.parent["menu"].onSelectionChanged.remove(self.selectionChanged)