private void _getGroupsByNameWorker_DoWork(object sender, DoWorkEventArgs e) { switch (_getGroupsByNameWorker.CancellationPending) { case true: e.Cancel = true; break; case false: { try { GroupListView.Dispatcher.InvokeAsync(() => { GroupListView.ItemsSource = _server.GetGroupsByName(GroupNameTextBox.Text); }); } catch (Exception ex) { ErrorOrSuccesTextBlock.Dispatcher.InvokeAsync(() => { ErrorOrSuccesTextBlock.Text += ex; }); } break; } } }