/// <summary>
/// Handles changes to the ContextMenu DependencyProperty.
/// </summary>
/// <param name="o">DependencyObject that changed.</param>
/// <param name="e">Event data for the DependencyPropertyChangedEvent.</param>
private static void OnContextMenuChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
{
FrameworkElement element = o as FrameworkElement;
if (null != element)
{
MenuFlyout oldContextMenu = e.OldValue as MenuFlyout;
if (null != oldContextMenu)
{
var holdListener = GetHoldListener(element);
holdListener.HoldingStarted -= OnHoldingStarted;
holdListener.HoldingEnded -= OnHoldingEnded;
holdListener.Dispose();
element.ClearValue(HoldListenerProperty);
element.ClearValue(ReleaseThresholdProperty);
}
MenuFlyout newContextMenu = e.NewValue as MenuFlyout;
if (null != newContextMenu)
{
var holdListener = new HoldListener(element);
holdListener.HoldingStarted += OnHoldingStarted;
holdListener.HoldingEnded += OnHoldingEnded;
SetHoldListener(element, holdListener);
}
}
}
private static void SetHoldListener(UIElement element, HoldListener value)
{
element.SetValue(HoldListenerProperty, value);
}
