Called when the Source collection changes.
protected virtual void OnSourceCollectionChanged(NotifyCollectionChangedEventArgs e)
The details of the collection change.
The implementation in SelectionNodeBase<T> calls Avalonia.Controls.Selection.SelectionNodeBase%601.OnItemsAdded(System.Int32%2cSystem.Collections.IList) and Avalonia.Controls.Selection.SelectionNodeBase%601.OnItemsRemoved(System.Int32%2cSystem.Collections.IList) in order to calculate how the collection change affects the currently selected items. It then calls OnIndexesChanged(Int32, Int32) and OnSelectionRemoved(Int32, Int32, IReadOnlyList<T?>) if necessary, according to the Avalonia.Controls.Selection.SelectionNodeBase%601.CollectionChangeState returned by those methods.
Override this method and OnSourceCollectionChangeFinished() to provide custom handling of source collection changes.