DiagramControl.QueryItemSnapping Event
Fires repeatedly as the end-user triggers snapping while dragging or resizing a diagram shape.
Namespace: DevExpress.Xpf.Diagram
Assembly: DevExpress.Xpf.Diagram.v20.2.dll
NuGet Packages: DevExpress.WindowsDesktop.Wpf.Diagram, DevExpress.Wpf.Diagram
Declaration
Event Data
The QueryItemSnapping event's data class is DiagramQueryItemSnappingEventArgs. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| Allow | Specifies whether to allow snapping of diagram items. |
| 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. |
| Item | Returns the item that is being dragged by the end-user. |
| 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. |
| SnapTo | Returns the diagram item to which the item being dragged by the end-user can be snapped. |
| Source | Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs. |
The event data class exposes the following methods:
| Method | Description |
|---|---|
| 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 SnapTo event’s parameter returns the item suitable for snapping (nearest in height/width when the end-user resizes an item or one lying on the same line when the end-user drags an item). The item that is being moved or resized is returned by the Item parameter. The Allow parameter specifies whether to enable snapping to the suitable item.