public GraphViewModel(IInspectorTool inspectorTool) { DisplayName = "[New Graph]"; _elements = new BindableCollection <ElementViewModel>(); _connections = new BindableCollection <ConnectionViewModel>(); _inspectorTool = inspectorTool; var element1 = AddElement <ImageSource>(100, 50); element1.Bitmap = BitmapUtility.CreateFromBytes(DesignTimeImages.Desert); var element2 = AddElement <ColorInput>(100, 300); element2.Color = Colors.Green; var element3 = AddElement <Add>(400, 250); Connections.Add(new ConnectionViewModel( element1.OutputConnector, element3.InputConnectors[0])); Connections.Add(new ConnectionViewModel( element2.OutputConnector, element3.InputConnectors[1])); element1.IsSelected = true; }