DiagramControl.ItemsChanged Event

Fires each time an item is added or removed from the diagram.

Namespace: DevExpress.Xpf.Diagram

Assembly: DevExpress.Xpf.Diagram.v24.2.dll

NuGet Package: DevExpress.Wpf.Diagram

Declaration

C#

public event EventHandler<DiagramItemsChangedEventArgs> ItemsChanged

VB.NET

Public Event ItemsChanged As EventHandler(Of DiagramItemsChangedEventArgs)

Event Data

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

Property	Description
Action	Indicates whether the item is being added or removed.
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 diagram item that is being added or removed from the diagram.
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.

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 ItemsChanged event fires whenever the DiagramControl.Items collection is modified (a document is loaded, a user performs the Undo/Redo actions, etc.).

The event parameter’s DiagramItemsChangedEventArgs.Action property indicates whether the item has been added or removed.