Wrap TreeWidget's invisible root item so that child items will receive tree change notifications

pyqtgraph/widgets/TreeWidget.py

@@ -168,7 +168,6 @@ class TreeWidget(QtGui.QTreeWidget):
         for i in xrange(item.childCount()):
             TreeWidget.informTreeWidgetChange(item.child(i))
         
-        
     def addTopLevelItem(self, item):
         QtGui.QTreeWidget.addTopLevelItem(self, item)
         self.informTreeWidgetChange(item)
@@ -209,6 +208,11 @@ class TreeWidget(QtGui.QTreeWidget):
         #for item in items:
             #self.informTreeWidgetChange(item)
 
+    def invisibleRootItem(self):
+        # wrap this item so that we can propagate tree change information
+        # to children.
+        return InvisibleRootItem(QtGui.QTreeWidget.invisibleRootItem(self))
+        
     def itemFromIndex(self, index):
         """Return the item and column corresponding to a QModelIndex.
         """
@@ -334,3 +338,46 @@ class TreeWidgetItem(QtGui.QTreeWidgetItem):
         elif (role in (QtCore.Qt.DisplayRole, QtCore.Qt.EditRole) and text != self.text(column)):
             treewidget.sigItemTextChanged.emit(self, column)
 
+            
+class InvisibleRootItem(QtGui.QTreeWidgetItem):
+    """Wrapper around a TreeWidget's invisible root item that calls
+    TreeWidget.informTreeWidgetChange when child items are added/removed.
+    """
+    def __init__(self, item):
+        self._real_item = item
+        
+    def addChild(self, child):
+        self._real_item.addChild(child)
+        TreeWidget.informTreeWidgetChange(child)
+            
+    def addChildren(self, childs):
+        self._real_item.addChildren(childs)
+        for child in childs:
+            TreeWidget.informTreeWidgetChange(child)
+
+    def insertChild(self, index, child):
+        self._real_item.insertChild(index, child)
+        TreeWidget.informTreeWidgetChange(child)
+    
+    def insertChildren(self, index, childs):
+        self._real_item.addChildren(index, childs)
+        for child in childs:
+            TreeWidget.informTreeWidgetChange(child)
+    
+    def removeChild(self, child):
+        self._real_item.removeChild(child)
+        TreeWidget.informTreeWidgetChange(child)
+            
+    def takeChild(self, index):
+        child = self._real_item.takeChild(index)
+        TreeWidget.informTreeWidgetChange(child)
+        return child
+    
+    def takeChildren(self):
+        childs = self._real_item.takeChildren()
+        for child in childs:
+            TreeWidget.informTreeWidgetChange(child)
+        return childs
+
+    def __getattr__(self, attr):
+        return getattr(self._real_item, attr)