diff -r 47b9ad1471cc -r d751b1c609b3 controls/CustomGrid.py
--- a/controls/CustomGrid.py	Mon Apr 23 11:16:40 2012 +0200
+++ b/controls/CustomGrid.py	Fri Apr 27 01:55:45 2012 +0200
@@ -72,16 +72,17 @@
                 button.Bind(wx.EVT_BUTTON, getattr(self, "On%sButton" % name))
     
     def RefreshButtons(self):
-        rows = self.Table.GetNumberRows()
-        row = self.GetGridCursorRow()
-        if self.AddButton is not None:
-            self.AddButton.Enable(self.Editable)
-        if self.DeleteButton is not None:
-            self.DeleteButton.Enable(self.Editable and rows > 0)
-        if self.UpButton is not None:
-            self.UpButton.Enable(self.Editable and row > 0)
-        if self.DownButton is not None:
-            self.DownButton.Enable(self.Editable and 0 <= row < rows - 1)
+        if self:
+            rows = self.Table.GetNumberRows()
+            row = self.GetGridCursorRow()
+            if self.AddButton is not None:
+                self.AddButton.Enable(self.Editable)
+            if self.DeleteButton is not None:
+                self.DeleteButton.Enable(self.Editable and rows > 0)
+            if self.UpButton is not None:
+                self.UpButton.Enable(self.Editable and row > 0)
+            if self.DownButton is not None:
+                self.DownButton.Enable(self.Editable and 0 <= row < rows - 1)
     
     def CloseEditControl(self):
         row, col = self.GetGridCursorRow(), self.GetGridCursorCol()