private void Deregister(BaseViewModel oldViewModel)
{
PagedViewModelWithPopups old = oldViewModel as PagedViewModelWithPopups;
if (old != null)
{
old.Popups.CollectionChanged -= _popupsCollectionChangedHandler;
old.CurrentPopupAllowsLightDismissChanged -= CurrentPopupAllowsLightDismissChanged;
}
}
protected override void OnViewModelChanged(PagedViewModel oldViewModel, PagedViewModel currentViewModel)
{
_listPresenter.ViewModels = ViewModel?.Popups;
Deregister(oldViewModel);
if (_popupsCollectionChangedHandler == null)
{
_popupsCollectionChangedHandler = new WeakEventHandler <NotifyCollectionChangedEventArgs>(Popups_CollectionChanged).Handler;
}
PagedViewModelWithPopups newModel = currentViewModel as PagedViewModelWithPopups;
if (newModel != null)
{
newModel.Popups.CollectionChanged += _popupsCollectionChangedHandler;
newModel.CurrentPopupAllowsLightDismissChanged += CurrentPopupAllowsLightDismissChanged;
}
UpdateVisibility();
UpdateLightDismiss();
base.OnViewModelChanged(oldViewModel, currentViewModel);
}