/// <summary>
/// Removes a handler from the attached Drop event.
/// </summary>
/// <param name="element">The DependencyObject to attach an event handler for.</param>
/// <param name="handler">The event handler.</param>
internal static void RemoveDropHandler(DependencyObject element, DragEventHandler handler)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
if (handler == null)
{
throw new ArgumentNullException("handler");
}
ExtendedRoutedEventHandlerCollection <DragEventHandler, DragEventArgs> handlers = element.GetDropHandlers();
if (handlers != null)
{
handlers.Remove(handler);
}
}
/// <summary>
/// Adds a handler to the attached Drop event.
/// </summary>
/// <param name="element">The DependencyObject to attach an event handler for.</param>
/// <param name="handler">The event handler.</param>
/// <param name="handledEventsToo">A value Indicating whether to invoke the handler if the event is handled.</param>
internal static void AddDropHandler(DependencyObject element, DragEventHandler handler, bool handledEventsToo)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
if (handler == null)
{
throw new ArgumentNullException("handler");
}
ExtendedRoutedEventHandlerCollection <DragEventHandler, DragEventArgs> originalHandlers = element.GetDropHandlers();
ExtendedRoutedEventHandlerCollection <DragEventHandler, DragEventArgs> handlers = originalHandlers ?? new ExtendedRoutedEventHandlerCollection <DragEventHandler, DragEventArgs>((h, a) => h(element, a));
handlers.Add(handler, handledEventsToo);
if (handlers != originalHandlers)
{
element.SetValue(DropHandlerProperty, handlers);
}
}
/// <summary>
/// Raises the attached DragLeave event on a element.
/// </summary>
/// <param name="element">The element to raise the event on.</param>
/// <param name="args">Information about the event.</param>
internal static void OnDragLeave(this DependencyObject element, SW.DragEventArgs args)
{
if (!args.Handled)
{
IAcceptDrop acceptDrop = element as IAcceptDrop;
if (acceptDrop != null)
{
acceptDrop.OnDragLeave(args);
}
}
ExtendedRoutedEventHandlerCollection <SW.DragEventHandler, SW.DragEventArgs> handlers = element.GetDragLeaveHandlers();
if (handlers != null)
{
handlers.Raise(args);
}
}
/// <summary>
/// Raises the attached GiveFeedback event on a element.
/// </summary>
/// <param name="element">The element to raise the event on.</param>
/// <param name="args">Information about the event.</param>
internal static void OnGiveFeedback(this DependencyObject element, SW.GiveFeedbackEventArgs args)
{
if (!args.Handled)
{
IAcceptDrop acceptDrop = element as IAcceptDrop;
if (acceptDrop != null)
{
acceptDrop.OnGiveFeedback(args);
}
}
ExtendedRoutedEventHandlerCollection <GiveFeedbackEventHandler, SW.GiveFeedbackEventArgs> handlers = element.GetGiveFeedbackHandlers();
if (handlers != null)
{
handlers.Raise(args);
}
}
