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DataGridRowsPresenter.OnCleanUpVirtualizedItem Method

Definition

Raises the CleanUpVirtualizedItem event for rows that have scrolled out of view.

protected:
 override void OnCleanUpVirtualizedItem(System::Windows::Controls::CleanUpVirtualizedItemEventArgs ^ e);
protected override void OnCleanUpVirtualizedItem (System.Windows.Controls.CleanUpVirtualizedItemEventArgs e);
override this.OnCleanUpVirtualizedItem : System.Windows.Controls.CleanUpVirtualizedItemEventArgs -> unit
Protected Overrides Sub OnCleanUpVirtualizedItem (e As CleanUpVirtualizedItemEventArgs)

Parameters

Remarks

By default, the DataGridRowsPresenter class maintains DataGridRow instances only for data items that are currently on display within the user interface. When rows are scrolled out of view, the DataGridRow instances become available for garbage collection.

This OnCleanUpVirtualizedItem method override cancels cleanup for rows that have validation errors. You can override this method or handle the CleanUpVirtualizedItem event to provide your own logic for canceling the cleanup of particular rows.

Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.

The OnCleanUpVirtualizedItem method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding OnCleanUpVirtualizedItem(CleanUpVirtualizedItemEventArgs) in a derived class, make sure to call the base class' OnCleanUpVirtualizedItem(CleanUpVirtualizedItemEventArgs) method so that registered delegates receive the event.

Applies to

See also