replace tkinter errormessage with custom create error dialog

daemon/core/gui/dialogs/mobilityconfig.py

@@ -29,12 +29,14 @@ class MobilityConfigDialog(Dialog):
         self.canvas_node = canvas_node
         self.node = canvas_node.core_node
         self.config_frame = None
+        self.has_error = False
         try:
             self.config = self.app.core.get_mobility_config(self.node.id)
+            self.draw()
         except grpc.RpcError as e:
-            show_grpc_error(e)
+            self.has_error = True
+            show_grpc_error(e, self.app, self.app)
             self.destroy()
-        self.draw()
 
     def draw(self):
         self.top.columnconfigure(0, weight=1)