/// <exception cref="T:System.ArgumentException">Could not find eventName on the Target.</exception>
private void RegisterEvent(object obj, string eventName)
{
EventInfo @event = obj.GetType().GetRuntimeEvent(eventName);
if (@event == null)
{
if (this.SourceObject == null)
{
return;
}
throw new ArgumentException("EventTrigger cannot find EventName");
}
else if (!EventTriggerBase.IsValidEvent(@event))
{
if (this.SourceObject == null)
{
return;
}
throw new ArgumentException("EventTriggerBase invalid event");
}
else
{
this.eventHandlerMethodInfo = typeof(EventTriggerBase).GetTypeInfo().GetDeclaredMethod("OnEventImpl");
Delegate handler = this.eventHandlerMethodInfo.CreateDelegate(@event.EventHandlerType, this);
WindowsRuntimeMarshal.AddEventHandler <Delegate>(
dlg => (EventRegistrationToken)@event.AddMethod.Invoke(obj, new object[] { dlg }),
etr => @event.RemoveMethod.Invoke(obj, new object[] { etr }), handler);
}
}
private static void OnSourceObjectChanged(DependencyObject obj, DependencyPropertyChangedEventArgs args)
{
EventTriggerBase eventTriggerBase = (EventTriggerBase)obj;
object newSource = (object)eventTriggerBase.SourceNameResolver.Object;
if (args.NewValue == null)
{
eventTriggerBase.OnSourceChanged(args.OldValue, newSource);
}
else
{
if (args.OldValue == null && newSource != null)
{
eventTriggerBase.UnregisterEvent(newSource, eventTriggerBase.GetEventName());
}
eventTriggerBase.OnSourceChanged(args.OldValue, args.NewValue);
}
}
