When we have a long running filter operation that can occur when filtering 50K+ items, what is the recommended best practice to cancel the filter operation and to show filter progress as it enumerates possibly all items? Is there any event that indicates when a filter operation has started and ended? These long running operations cause the UI to completely freeze until the filtering operation has completed. Is there a recommended way to prevent this UI freeze such as when or where to "IsFilterActive" that kicks off the Filter operation? We use a custom PredicateFilter that is set prior to setting
It appears the only property available is TreeListBox.IsFilterActive.