delete node

Hello,

When the user select some of the nodes and press delete key, I only want to change the appearance of the nodes and make it cannot be selected and moved, so I add a property IsDeleted in my node model, and write my own node remover, in the node remover I only set the IsDeleted property of the nodes to true, and I add some triggers in FullDiagramNodeTemplate:

<DataTrigger Binding="{Binding Content.IsDeleted, RelativeSource={RelativeSource TemplatedParent}}" Value="True">
            <Setter TargetName="Mover" Property="Visibility" Value="Collapsed" />
            <Setter TargetName="Mover" Property="IsEnabled" Value="False" />
            <Setter TargetName="Mover" Property="IsHitTestVisible" Value="False" />

But it doesn't work, the node can be selected and moved, so what should I do?

Thanks

Hello,

I have fixed this by changing the "Content.IsDeleted" to "Node.IsDeleted", now the mover is collapsed, and the node can not be selected singlely.

But it still can be selected with the other node together, and can be moved with the other nodes, how can I make it not selectable, and how can I make a connection not selectable.

Thanks

Hello Jzhou

Good to see you solved the binding issue. I'll have a look next week at the best way to disable selection for individual nodes and connections.

Jason Fauchelle

Hello Jzhou

Here is the best way I've found to handle this selection logic. Attach a handler to the DiagramSurface that listens to the ListBoxItem.SelectedEvent. Here is how this would look:

ds.AddHandler(ListBoxItem.SelectedEvent, new RoutedEventHandler(ItemSelected), true);

Then in the handler, you can check e.OriginalSource to get the selected element. If the element is a node element, and the model of this element has IsDeleted set to true, then deselect the element. Similar logic can be used for connections. Here is an example:

private void ItemSelected(object sender, RoutedEventArgs e)
{
  DiagramNodeElement nodeElement = e.OriginalSource as DiagramNodeElement;
  if (nodeElement != null)
  {
    SampleNode node = nodeElement.Node as SampleNode;
    if (node != null && node.IsDeleted)
    {
      nodeElement.IsSelected = false;
    }
  }
  else
  {
    DiagramConnectionElement connectionElement = e.OriginalSource as DiagramConnectionElement;
    if (connectionElement != null)
    {
      connectionElement.IsSelected = false;
    }
  }
}

SampleNode is just a node implementation that has the IsDeleted property. My connection logic example simply prevents any connection from ever being selected.

Jason Fauchelle