Fires before the expanded state of the Navigation Pane is changed.
The NavPaneExpandedChanging event's data class is NavPaneExpandedChangingEventArgs. The following properties provide information specific to this event:
|Cancel||Gets or sets a value indicating whether the operation which raised an event should be canceled.|
|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.|
|IsExpanded||Gets a value indicating whether the Navigation Pane is expanded. Inherited from NavPaneExpandedChangedEventArgs.|
|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:
|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.|
The NavPaneExpandedChanging event occurs when the Navigation Pane's expanded state is going to be changed within the NavBarControl. This event allows you to cancel expanded state changing, if required.