Ignore parent in PreviewMouseButtonDown on TreeviewItem

Question

I have a treeview and im trying to implement a drag and drop functionallity.

<TreeView.ItemContainerStyle>
    <Style TargetType="{x:Type TreeViewItem}">
         <EventSetter Event="TreeViewItem.PreviewMouseLeftButtonDown" Handler="PreviewMouseLeftButtonDown" />
    </Style>
</TreeView.ItemContainerStyle>

Then i have an event in the code behind to handle the click, and start the drag:

void PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    if (sender is TreeViewItem)
    {
       //clone the tree item, create an adorner, apply adorner
       //doDragDrop
    }
}

My problem is since PreviewMouseLftButtonDown is a routed event using the tunneling strategy, when the mouse is clicked on a treenode item, I get the root node first. I am not interested in the root node, only the leaf nodes. My structure is like this:

HeaderNodeObject
   |_LeafnodeObject
   |_LeafNodeOject

So in my event I need to basically not do anything and just proceed if the sender treeViewItem is a HeaderNodeObject. But how can i tell what it is? the sender comes in as a treeViewItem, im not sure how to tell what the object it holds is.

Answer 1

I solved this fairly simply by just checking if the itemsource on the sender is null. If its null that means its a leaf node:

if (sender is TreeViewItem)
{
   Item = sender as TreeViewItem;

    //make sure we have a leaf node, if we dont just move on.
    if (Item.ItemsSource == null)
    {
     //do my stuff
    }
}