private void ImplicitAnimationSetVectorChanged(IObservableVector <DependencyObject> sender, IVectorChangedEventArgs @event)
        {
            if (@event.CollectionChange == CollectionChange.ItemInserted ||
                @event.CollectionChange == CollectionChange.ItemChanged)
            {
                IImplicitTimeline item = (IImplicitTimeline)sender[(int)@event.Index];

                item.AnimationPropertyChanged -= RaiseAnimationsChanged;
                item.AnimationPropertyChanged += RaiseAnimationsChanged;
            }

            AnimationsChanged?.Invoke(this, EventArgs.Empty);
        }
 private void RaiseAnimationsChanged(object sender, EventArgs e)
 {
     AnimationsChanged?.Invoke(this, e);
 }