--- a/PLCOpenEditor.py	Wed Dec 16 14:36:44 2009 +0100
+++ b/PLCOpenEditor.py	Wed Dec 16 14:53:01 2009 +0100
@@ -4106,7 +4106,12 @@
         self.VariablesGrid.SetSelectionBackground(wx.WHITE)
         self.VariablesGrid.SetSelectionForeground(wx.BLACK)
         self.VariablesGrid.SetDropTarget(DebugVariableDropTarget(self))
-        self.VariablesGrid.Bind(wx.grid.EVT_GRID_CELL_RIGHT_CLICK, self.OnVariablesGridRightClick)
+        if wx.VERSION >= (2, 6, 0):
+            self.VariablesGrid.Bind(wx.grid.EVT_GRID_SELECT_CELL, self.OnVariablesGridCellSelect)
+            self.VariablesGrid.Bind(wx.grid.EVT_GRID_CELL_RIGHT_CLICK, self.OnVariablesGridCellRightClick)
+        else:
+            wx.grid.EVT_GRID_SELECT_CELL(self.VariablesGrid, self.OnVariablesGridCellSelect)
+            wx.grid.EVT_GRID_CELL_RIGHT_CLICK(self.VariablesGrid, self.OnVariablesGridCellRightClick)
         
         self.UpButton = wx.Button(id=ID_DEBUGVARIABLEPANELUPBUTTON, label='^',
               name='UpButton', parent=self, pos=wx.Point(0, 0),
@@ -4141,6 +4146,7 @@
             self.VariablesGrid.SetColSize(col, 100)
         
         self.Table.ResetView(self.VariablesGrid)
+        self.RefreshButtons()
     
     def RefreshNewData(self):
         if self.HasNewData:
@@ -4174,7 +4180,11 @@
             self.ReleaseDataValue(iec_path)
         return ReleaseVariableFunction
     
-    def OnVariablesGridRightClick(self, event):
+    def OnVariablesGridCellSelect(self, event):
+        wx.CallAfter(self.RefreshButtons)
+        event.Skip()
+    
+    def OnVariablesGridCellRightClick(self, event):
         row, col = event.GetRow(), event.GetCol()
         if self.Table.GetColLabelValue(col, False) == "Value":
             iec_path = self.Table.GetValueByName(row, "Variable").upper()
@@ -4193,6 +4203,16 @@
             self.PopupMenu(menu)
         event.Skip()
     
+    def RefreshButtons(self):
+        if getattr(self, "Table", None):
+            table_length = len(self.Table.data)
+            row = 0
+            if table_length > 0:
+                row = self.VariablesGrid.GetGridCursorRow()
+            self.DeleteButton.Enable(table_length > 0)
+            self.UpButton.Enable(table_length > 0 and row > 0)
+            self.DownButton.Enable(table_length > 0 and row < table_length - 1)
+    
     def OnDeleteButton(self, event):
         idx = self.VariablesGrid.GetGridCursorRow()
         if idx >= 0:
@@ -4200,6 +4220,7 @@
             self.RemoveDataConsumer(item)
             self.Table.RemoveItem(idx)
             self.RefreshGrid()
+            self.RefreshButtons()
         event.Skip()
 
     def OnUpButton(self, event):
@@ -4221,6 +4242,7 @@
         if result is not None:
             self.Table.InsertItem(idx, item)
             self.RefreshGrid()
+            self.RefreshButtons()
 
     def MoveValue(self, idx, move):
         new_idx = max(0, min(idx + move, self.Table.GetNumberRows() - 1))
@@ -4228,7 +4250,8 @@
             self.Table.MoveItem(idx, new_idx)
             self.RefreshGrid()
             self.VariablesGrid.SetGridCursor(new_idx, self.VariablesGrid.GetGridCursorCol())
-    
+            self.RefreshButtons()
+            
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 #                               Viewer Printout
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