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Is it possible to create a weak event listener on a static event using WeakEventManager?
I would like to create a weak event listener on the static CompositionTarget.Rendering event to avoid memory leaks when I don't know the lifetime of the WPF/Silverlight source element.
I implemented the rendering event manager by the weak event pattern:
public class RenderingEventManager : WeakEventManager
{
public static void AddListener(IWeakEventListener listener)
{
CurrentManager.ProtectedAddListener(null, listener);
}
public static void RemoveListener(IWeakEventListener listener)
{
CurrentManager.ProtectedRemoveListener(null, listener);
}
private static RenderingEventManager CurrentManager
{
get
{
var managerType = typeof(RenderingEventManager);
var manager = (RenderingEventManager)GetCurrentManager(managerType);
if (manager == null)
{
manager = new RenderingEventManager();
SetCurrentManager(managerType, manager);
}
return manager;
}
}
protected sealed override void StartListening(object source)
{
CompositionTarget.Rendering += this.OnCompositionTargetRendering;
}
protected sealed override void StopListening(object source)
{
CompositionTarget.Rendering -= this.OnCompositionTargetRendering;
}
void OnCompositionTargetRendering(object sender, EventArgs e)
{
this.DeliverEvent(sender, e);
}
}
and tested the manager in a simple window:
public partial class Window1 : Window, IWeakEventListener
{
public Window1()
{
InitializeComponent();
RenderingEventManager.AddListener(this);
}
bool IWeakEventListener.ReceiveWeakEvent(Type managerType, object sender, EventArgs e)
{