Export (0) Print
Expand All
Expand Minimize

PropertyChangedCallback Delegate

Represents the callback that is invoked when the effective property value of a dependency property changes.

Namespace:  System.Windows
Assembly:  WindowsBase (in WindowsBase.dll)

public delegate void PropertyChangedCallback(
	DependencyObject d,
	DependencyPropertyChangedEventArgs e
)
In XAML, you can use delegates but you cannot define your own.

Parameters

d
Type: System.Windows.DependencyObject

The DependencyObject on which the property has changed value.

e
Type: System.Windows.DependencyPropertyChangedEventArgs

Event data that is issued by any event that tracks changes to the effective value of this property.

The following example registers a new dependency property, using the signature that specifies a PropertyChangedCallback. The PropertyChangedCallback is used to create a callback that changes an internal property whenever the public property changes.

public static readonly DependencyProperty AquariumGraphicProperty = DependencyProperty.Register(
  "AquariumGraphic",
  typeof(Uri),
  typeof(AquariumObject),
  new FrameworkPropertyMetadata(null,
      FrameworkPropertyMetadataOptions.AffectsRender, 
      new PropertyChangedCallback(OnUriChanged)
  )
);
private static void OnUriChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) {
  Shape sh = (Shape) d;
  sh.Fill = new ImageBrush(new BitmapImage((Uri)e.NewValue));
}

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0

Community Additions

ADD
Show:
© 2014 Microsoft