如何触发TreeView LostFocus事件

Question

I have a TreeView like this:

        <TreeView LostFocus="treeView_LostFocus">
            <TreeViewItem Selected="treeViewItem_select"/>
        </TreeView>

it always trigger event treeView_LostFocus first when I select different item in TreeViewItem using treeViewItem_select . How can I do to trigger the lost focus event only when the the TreeView losing focus, not before trigger treeViewItem_select ?

ps: make e.Handle = true in the end of treeViewItem_select seems not work.

Answer 1

A solution is to check if the KeyboardFocus is still within the TreeView.

private void treeView_LostFocus(object sender, RoutedEventArgs e)
{
    var tv = sender as TreeView;

    if (tv.IsKeyboardFocusWithin == false)
    {
        //Your code
    }
}

That way when your child items get focus, your code won't get executed. Only when the whole TreeView loses focus.