Snackbar DeactivateStoryboardCompletedEvent Bug

Dieses Issue hat noch niemand übernommen.

I think this is a bug...

**.../MaterialDesignThemes.Wpf/Snackbar.cs**

```

public static readonly RoutedEvent DeactivateStoryboardCompletedEvent = EventManager.RegisterRoutedEvent(
nameof(DeactivateStoryboardCompleted), RoutingStrategy.Bubble, typeof(SnackbarMessageEventArgs), typeof(Snackbar));

public event RoutedPropertyChangedEventHandler DeactivateStoryboardCompleted
{
add => AddHandler(DeactivateStoryboardCompletedEvent, value);
remove => RemoveHandler(DeactivateStoryboardCompletedEvent, value);
}

private static void OnDeactivateStoryboardCompleted(IInputElement snackbar, SnackbarMessage message)
{
var args = new SnackbarMessageEventArgs(DeactivateStoryboardCompletedEvent, message);
snackbar.RaiseEvent(args);
}

```

Prompt type mismatch when I register events...

I didn't look at all the code. Maybe it's right?

```

public static readonly RoutedEvent DeactivateStoryboardCompletedEvent = EventManager.RegisterRoutedEvent(
nameof(DeactivateStoryboardCompleted), RoutingStrategy.Bubble, typeof(RoutedPropertyChangedEventHandler), typeof(Snackbar));

public event RoutedPropertyChangedEventHandler DeactivateStoryboardCompleted
{
add => AddHandler(DeactivateStoryboardCompletedEvent, value);
remove => RemoveHandler(DeactivateStoryboardCompletedEvent, value);
}

private static void OnDeactivateStoryboardCompleted(IInputElement snackbar, SnackbarMessage message)
{
var snackbarMessageEventArgs = new SnackbarMessageEventArgs(DeactivateStoryboardCompletedEvent, snackbar, message);
var args = new RoutedPropertyChangedEventArgs(snackbarMessageEventArgs, snackbarMessageEventArgs, DeactivateStoryboardCompletedEvent);
snackbar.RaiseEvent(args);
}

```

Beginne in MaterialDesignThemes.Wpf/Snackbar.cs und überprüfe gemeinsam die Registrierung des DeactivateStoryboardCompleted-Ereignisses, die Delegatdeklaration und den Aufruf von OnDeactivateStoryboardCompleted. Überprüfe die beteiligten WPF-Routed-Event-Typen und erstelle das Projekt, um zu bestätigen, dass der gemeldete Typkonflikt behoben ist, ohne einen weiteren Fehler bei der Ereignissignatur einzuführen.

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