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CompositionTarget.Rendering Event

Definition

Occurs just before the objects in the composition tree are rendered.

public:
 static event EventHandler ^ Rendering;
public static event EventHandler Rendering;
member this.Rendering : EventHandler 
Public Shared Custom Event Rendering As EventHandler 

Event Type

Examples

The Rendering event is raised during the Windows Presentation Foundation (WPF) rendering process. The following example shows how you register an EventHandler delegate to the static Rendering method on CompositionTarget.

// Add an event handler to update canvas background color just before it is rendered.
CompositionTarget.Rendering += UpdateColor;
' Add an event handler to update canvas background color just before it is rendered.
AddHandler CompositionTarget.Rendering, AddressOf UpdateColor

You can use your rendering event handler to create custom drawing content. This event handler gets called once per frame. Each time that Windows Presentation Foundation (WPF) marshals the persisted rendering data in the visual tree across to the composition tree, your event handler is called. In addition, if changes to the visual tree force updates to the composition tree, your event handler is also called. Note that your event handler is called after layout has been computed. However, you can modify layout in your event handler, which means that layout will be computed once more before rendering.

Remarks

The Rendering event is routed to the specified event handler after animation and layout have been applied to the composition tree.

Applies to