DataViewBase.GiveRecordDragFeedback Event

Occurs continuously while a drag-and-drop operation is in progress, and enables the drag source to give feedback to the user.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v20.1.Core.dll

Declaration

public event EventHandler<GiveRecordDragFeedbackEventArgs> GiveRecordDragFeedback
Public Event GiveRecordDragFeedback As EventHandler(Of GiveRecordDragFeedbackEventArgs)

Event Data

The GiveRecordDragFeedback event's data class is GiveRecordDragFeedbackEventArgs. The following properties provide information specific to this event:

Property Description
Data Gets or sets a data object that contains the data associated with the DataViewBase.GiveRecordDragFeedback event.
Effects Gets or sets the target drag-and-drop operation.
Handled Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route. Inherited from RoutedEventArgs.
OriginalSource Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class. Inherited from RoutedEventArgs.
RoutedEvent Gets or sets the RoutedEvent associated with this RoutedEventArgs instance. Inherited from RoutedEventArgs.
Source Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.
UseDefaultCursors Gets or sets whether a drag operation should use the default cursors that are associated with drag-drop effects.

Remarks

You can use the GiveRecordDragFeedback to change the mouse pointer appearance to indicate the effects allowed by the drop target.

The DataViewBase.DragRecordOver event is paired with the GiveRecordDragFeedback event. In the DataViewBase.DragRecordOver event handler, you can check whether any modifier keys are pressed, which typically indicates whether the user intends a move or a copy action. After these checks are performed, you set DragEventArgsBase.Effects property to notify the drag source what effect dropping the data will have. The drag source receives this information in the GiveRecordDragFeedbackEventArgs.Effects property of the GiveRecordDragFeedback event arguments, and can set an appropriate cursor to give feedback to the user.

The code sample below shows how to display an arrow symbol for moving nodes to another node's child collection:

<dxg:GridControl>
   <!----> 
   <dxg:GridControl.View>
      <dxg:TreeListView AllowDragDrop="True" DragRecordOver="OnDragRecordOver" GiveRecordDragFeedback="OnGiveRecordDragFeedback" />
   </dxg:GridControl.View>
</dxg:GridControl>
void OnDragRecordOver(object sender, DragRecordOverEventArgs e) {
   if (e.DropPosition == DropPosition.Inside) {
      e.Effects = DragDropEffects.Link;
      e.Handled = true;
   }
}
void OnGiveRecordDragFeedback(object sender, GiveRecordDragFeedbackEventArgs e) {
   if (e.Effects == DragDropEffects.Link) {
      Mouse.SetCursor(Cursors.UpArrow);
   } else {
      e.UseDefaultCursors = true;
   }
   e.Handled = true;
}
See Also