• Article

TreeViewItem.OnCollapsed Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Raises a Collapsed event when the IsExpanded property changes from true to false.

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

Syntax

'Declaration
Protected Overridable Sub OnCollapsed ( _
    e As RoutedEventArgs _
)

protected virtual void OnCollapsed(
    RoutedEventArgs e
)

Parameters

Remarks

This method updates the visual state of the TreeViewItem when the value of the IsExpanded changes, and then raises the Collapsed event.

Raising an event invokes the event handler through a delegate. The OnCollapsed method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding OnCollapsed in a derived class, make sure to call the base class’s OnCollapsed method so that registered delegates receive the event.

Version Information

Silverlight

Supported in: 5, 4, 3

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.