--- a/graphics/GraphicCommons.py	Wed Sep 19 13:32:24 2007 +0200
+++ b/graphics/GraphicCommons.py	Wed Sep 19 15:20:59 2007 +0200
@@ -24,7 +24,7 @@
 
 import wx
 from math import *
-
+from plcopen.structures import IsOfType
 
 #-------------------------------------------------------------------------------
 #                               Common constants
@@ -707,6 +707,10 @@
     def GetType(self):
         return self.Type
     
+    # Returns if connector type is compatible with type given
+    def IsCompatible(self, type):
+        return IsOfType(type, self.Type) or IsOfType(self.Type, type)
+    
     # Changes the connector name
     def SetType(self, type):
         self.Type = type
@@ -968,10 +972,29 @@
     def GetStartConnected(self):
         return self.StartConnected
     
+    # Returns connector to which start point is connected
+    def GetStartConnectedType(self):
+        if self.StartConnected:
+            return self.StartConnected.GetType()
+        return None
+    
     # Returns connector to which end point is connected
     def GetEndConnected(self):
         return self.EndConnected
     
+    # Returns connector to which end point is connected
+    def GetEndConnectedType(self):
+        if self.EndConnected:
+            return self.EndConnected.GetType()
+        return None
+    
+    def IsConnectedCompatible(self):
+        if self.StartConnected:
+            return self.StartConnected.IsCompatible(self.GetEndConnectedType())
+        elif self.EndConnected:
+            return True
+        return False
+    
     # Unconnect the start and end points
     def Clean(self):
         if self.StartConnected:
@@ -1609,13 +1632,13 @@
             new_pos = wx.Point(self.Points[handle].x + movex, self.Points[handle].y + movey)
             connector = self.Parent.FindBlockConnector(new_pos)
             if connector:
-                if handle == 0 and self.EndConnected != connector:
+                if handle == 0 and self.EndConnected != connector and connector.IsCompatible(self.GetEndConnectedType()):
                     connector.Connect((self, handle))
                     self.SetStartPointDirection(connector.GetDirection())
                     self.ConnectStartPoint(connector.GetPosition(), connector)
                     self.oldPos = connector.GetPosition()
                     self.Dragging = False
-                elif handle != 0 and self.StartConnected != connector:
+                elif handle != 0 and self.StartConnected != connector and connector.IsCompatible(self.GetStartConnectedType()):
                     connector.Connect((self, handle))
                     self.SetEndPointDirection(connector.GetDirection())
                     self.ConnectEndPoint(connector.GetPosition(), connector)