Hi, I have a TreeVIew WPF with 2 Levels of Data. I have deleted the ToogleButton from the TreeViewItemTemplate. Now I'd like to expand / collapse the groups with a single mouse-click (not with a double click as the default behaviour). I have tried in this way:

Private Sub tvArt_SelectedItemChanged(ByVal sender As System.Object, _ ByVal e As RoutedPropertyChangedEventArgs(Of System.Object)) Handles tvArt.SelectedItemChanged

If e.NewValue Is Nothing = False Then
    Dim ri As P_RicambiItem = TryCast(e.NewValue, P_RicambiItem)
    If ri Is Nothing = False Then
        If ri.isExpanded Then
            ri.isExpanded = False
        Else
            ri.isExpanded = True
        End If
        ri.isSelected = False
    End If
End If

End Sub

Using my properties "isExpanded" and "isSelected" in the collection data source. But it works only halfway: after the first click, infact, I can't click for a second time on the same item, because, even if I've deselected it, the event handler "remembers" that it was the last selected item and it doesn't capture the event "SelectedItemChanged". How can I do? Thanks a lot, Pileggi