private void OnWrapOptionsAppBarButtonClick(object sender, RoutedEventArgs e) { var dialog = new WrapOptionsSelect() { TextWrapping = this.txtbox.TextWrapping }; // Bind dialog to TextBox Binding binding = new Binding { Source = dialog, Path = new PropertyPath("TextWrapping"), Mode = BindingMode.TwoWay }; txtbox.SetBinding(TextBox.TextWrappingProperty, binding); var popup = new Popup() { Child = dialog, IsLightDismissEnabled = true }; popup.IsOpen = true; }