Can I rollback collection changes on collection changed event?

Question

I have 2 list views...and add/remove buttons between them.

On collection changed event of a list-view-collection in viewmodel, can i rollback the changes for a particula

Answer 1

Shimmy's answer didn't work for me on a Windows Store application, you'll still run into re-entrancy issues and get an InvalidOperationException saying "Cannot change ObservableCollection during a CollectionChanged event."

I had to use the UI's dispatcher and disable/enable the event handler to avoid these issues.

Be warned: this is a hack, and the framework designers went to great lengths to prevent you from doings this. So if you want to ignore their warning, be careful not to shoot yourself in the foot.

Items.CollectionChanged += ItemsChanged;

private async void ItemsChanged(object sender, NotifyCollectionChangedEventArgs e)
{
    if(condition)
    {
        //rollback
        await CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(
            CoreDispatcherPriority.Normal, () => {

                //disable/enable event handler
                Items.CollectionChanged -= ItemsChanged;

                Items.Remove(e.NewItems[0]);

                Items.CollectionChanged += ItemsChanged;
            })).AsTask();
    }
}

This will avoid the exception, avoid calling the handler recursively, and update the UI correctly.