LostFocusEventManager Class

Provides a WeakEventManager implementation so that you can use the "weak event listener" pattern to attach listeners for the UIElement.LostFocus or ContentElement.LostFocus events.

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

'Declaration
Public Class LostFocusEventManager _
	Inherits WeakEventManager

The LostFocusEventManager type exposes the following members.

  NameDescription
Public propertyDispatcherGets the Dispatcher this DispatcherObject is associated with. (Inherited from DispatcherObject.)
Protected propertyItemGets or sets the data being stored for the specified source. (Inherited from WeakEventManager.)
Protected propertyReadLockEstablishes a read-lock on the underlying data table, and returns an IDisposable. (Inherited from WeakEventManager.)
Protected propertyWriteLockEstablishes a write-lock on the underlying data table, and returns anIDisposable. (Inherited from WeakEventManager.)
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  NameDescription
Public methodStatic memberAddHandlerAdds the specified event handler, which is called when specified source raises the UIElement.LostFocus or ContentElement.LostFocus event.
Public methodStatic memberAddListenerAdds the provided listener to the list of listeners on the provided source.
Public methodCheckAccessDetermines whether the calling thread has access to this DispatcherObject. (Inherited from DispatcherObject.)
Protected methodDeliverEventDelivers the event being managed to each listener. (Inherited from WeakEventManager.)
Protected methodDeliverEventToListDelivers the event being managed to each listener in the provided list. (Inherited from WeakEventManager.)
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Protected methodNewListenerListReturns a new object to contain listeners to the UIElement.LostFocus or ContentElement.LostFocus event. (Overrides WeakEventManager.NewListenerList.)
Protected methodProtectedAddHandlerAdds the specified delegate as an event handler of the specified source. (Inherited from WeakEventManager.)
Protected methodProtectedAddListenerAdds the provided listener to the provided source for the event being managed. (Inherited from WeakEventManager.)
Protected methodProtectedRemoveHandlerRemoves the previously added handler from the specified source. (Inherited from WeakEventManager.)
Protected methodProtectedRemoveListenerRemoves a previously added listener from the provided source. (Inherited from WeakEventManager.)
Protected methodPurgeRemoves inactive listener entries from the data list for the provided source. Returns true if some entries were actually removed from the list. (Inherited from WeakEventManager.)
Protected methodRemoveRemoves all listeners for the specified source. (Inherited from WeakEventManager.)
Public methodStatic memberRemoveHandlerRemoves the specified event handler from the specified source.
Public methodStatic memberRemoveListenerRemoves the specified listener from the list of listeners on the provided source.
Protected methodScheduleCleanupRequests that a purge of unused entries in the underlying listener list be performed on a lower priority thread. (Inherited from WeakEventManager.)
Protected methodStartListeningBegins listening for the LostFocus event on the given source, attaching an internal class handler to that source. (Overrides WeakEventManager.StartListening(Object).)
Protected methodStopListeningStops listening for the LostFocus event on the given source. (Overrides WeakEventManager.StopListening(Object).)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
Public methodVerifyAccessEnforces that the calling thread has access to this DispatcherObject. (Inherited from DispatcherObject.)
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In order to be listeners in this pattern, your listener objects must implement IWeakEventListener. You do not need to implement IWeakEventListener on the class that is the source of the events.

WPF data binding uses this WeakEventManager so that internal classes that update bindings can attach listeners for a UIElement.LostFocus or ContentElement.LostFocus event on an object that is the target of a binding. This supports notification for the LostFocus mode of data binding, without creating strong references to data binding targets.

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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