Handling collection-changed events

The following example demonstrates how to subscribe to the CollectionChanged event of the DataGridCollectionView.SortDescriptions collection's INotifyCollectionChanged interface implementation to be notified when sorting applied to a grid's columns changes.

VB.NET	Copy Code
Protected Overrides Sub OnInitialized(ByVal e As EventArgs) MyBase.OnInitialized(e) Dim view As DataGridCollectionView = TryCast(Me.OrdersGrid.ItemsSource, DataGridCollectionView) AddHandler (CType(view.SortDescriptions, INotifyCollectionChanged)).CollectionChanged, AddressOf SortCollectionChanged End Sub Private Sub SortCollectionChanged(ByVal sender As Object, ByVal e As NotifyCollectionChangedEventArgs) Debug.WriteLine("Sort changed") End Sub

VB.NET

Copy Code

Protected Overrides Sub OnInitialized(ByVal e As EventArgs)
  MyBase.OnInitialized(e)

  Dim view As DataGridCollectionView = TryCast(Me.OrdersGrid.ItemsSource, DataGridCollectionView)
  AddHandler (CType(view.SortDescriptions, INotifyCollectionChanged)).CollectionChanged,
                                           AddressOf SortCollectionChanged
End Sub
Private Sub SortCollectionChanged(ByVal sender As Object, ByVal e As NotifyCollectionChangedEventArgs)
  Debug.WriteLine("Sort changed")
End Sub

C#	Copy Code
protected override void OnInitialized( EventArgs e ) { base.OnInitialized( e ); DataGridCollectionView view = this.OrdersGrid.ItemsSource as DataGridCollectionView; ( ( INotifyCollectionChanged )view.SortDescriptions ).CollectionChanged += new NotifyCollectionChangedEventHandler( this.SortCollectionChanged ); } private void SortCollectionChanged( object sender, NotifyCollectionChangedEventArgs e ) { Debug.WriteLine( "Sort changed" ); }

Copy Code

protected override void OnInitialized( EventArgs e )
{
  base.OnInitialized( e ); 
  DataGridCollectionView view = this.OrdersGrid.ItemsSource as DataGridCollectionView;
  ( ( INotifyCollectionChanged )view.SortDescriptions ).CollectionChanged +=
                                      new NotifyCollectionChangedEventHandler( this.SortCollectionChanged );
} 
private void SortCollectionChanged( object sender, NotifyCollectionChangedEventArgs e )
{
  Debug.WriteLine( "Sort changed" );
}