private void Stk_MouseLeftButtonDown(object sender, RoutedEventArgs e) { if (!HasItems) { IsSelected = true; if (IsChoosed == false) { IsChoosed = true; } else { e.Handled = true; return; } ParentTreeView.OnChoosedItemChanged(); } else { IsSelected = false; if (!ParentTreeView.IsExpandDoubleClick) { IsExpanded = !IsExpanded; } } }