TreeViewControl.DragRecordOver Event
Occurs continuously while a drag-and-drop operation is in progress.
Namespace: DevExpress.Xpf.Grid
Assembly: DevExpress.Xpf.Grid.v24.1.dll
NuGet Package: DevExpress.Wpf.Grid.Core
Declaration
Event Data
The DragRecordOver event's data class is DragRecordOverEventArgs. The following properties provide information specific to this event:
Property | Description |
---|---|
AllowedEffects | Gets a member of the DragDropEffects enumeration that specifies which operations are allowed by the originator of the drag event. Inherited from DragEventArgsBase. |
Data | Gets or sets a data object that contains the data associated with the corresponding drag event. Inherited from DragEventArgsBase. |
DropPosition | Gets a drop position that specifies how a record is placed after it has been dropped. Inherited from DragEventArgsBase. |
DropPositionRelativeCoefficient | Gets a number between 0 and 1, presenting a drop position relative to the target record. |
Effects | Gets or sets the target drag-and-drop operation. Inherited from DragEventArgsBase. |
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. |
IsFromOutside | Gets whether the dragged record is from another control. Inherited from DragEventArgsBase. |
KeyStates | Gets a flag enumeration indicating the current state of the SHIFT, CTRL, and ALT keys, as well as the state of the mouse buttons. Inherited from DragEventArgsBase. |
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. |
TargetRecord | Gets a record that is drop target. Inherited from DragEventArgsBase. |
TargetRowHandle | Gets the target row handle. Inherited from DragEventArgsBase. |
The event data class exposes the following methods:
Method | Description |
---|---|
GetRecordType() | Gets the Type of the transferred records. Inherited from DragEventArgsBase. |
InvokeEventHandler(Delegate, Object) | When overridden in a derived class, provides a way to invoke event handlers in a type-specific way, which can increase efficiency over the base implementation. Inherited from RoutedEventArgs. |
OnSetSource(Object) | When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes. Inherited from RoutedEventArgs. |
Remarks
The following code sample does not allow users to drop records to the root level.
<dxg:TreeViewControl x:Name="treeview"
AllowDragDrop="True"
DragRecordOver="treeview_DragRecordOver"/>
void treeview_DragRecordOver(object sender, DevExpress.Xpf.Core.DragRecordOverEventArgs e) {
TreeListNode node = treeview.GetNodeByRowHandle(e.TargetRowHandle);
if (node != null && node.Level == 0) {
e.Effects = DragDropEffects.None;
e.Handled = true;
}
}
For information about drag-and-drop operations, refer to the following DevExpress WPF Grid help topic: Drag-and-Drop.
See Also