ComponentDispatcher Class

Definition

Namespace:

System.Windows.Interop

Assembly:

WindowsBase.dll

Enables shared control of the message pump between Win32 and WPF in interoperation scenarios.

public ref class ComponentDispatcher abstract sealed

public static class ComponentDispatcher

type ComponentDispatcher = class

Public Class ComponentDispatcher

Inheritance

Object

ComponentDispatcher

Remarks

Although the class itself is static, all members of ComponentDispatcher are specific to a particular thread. For example, if you examine the value of IsThreadModal on two different threads, you might get different values.

The methods are static but they are backed by per-thread data structures. The static methods allow singleton access but the ComponentDispatcher is sorting out the appropriate per-thread operations.

The owner of the message pump is defined by the code that calls the Win32 function GetMessage. The owner calls RaiseThreadMessage for every keyboard message. This method raises the ThreadFilterMessage event with the messages contained in the event data. If that event is not handled, the owner raises the ThreadPreprocessMessage event with the messages contained in the event argument.

Note

Only keyboard messages are supported.

Properties

CurrentKeyboardMessage	Gets the last message that was raised.
IsThreadModal	Gets a value that indicates whether the thread is modal.

Methods

PopModal()	Called to indicate that a modal thread is no longer modal.
PushModal()	Called to indicate that the thread is modal.
RaiseIdle()	Called to indicate that a thread is idle.
RaiseThreadMessage(MSG)	Indicates that a new message is available for possible handling.

Events

EnterThreadModal	Occurs when a thread becomes modal.
LeaveThreadModal	Occurs when a modal thread becomes nonmodal.
ThreadFilterMessage	Occurs when the message pump receives a keyboard message.
ThreadIdle	Occurs when the thread is idle.
ThreadPreprocessMessage	Occurs when the message pump receives a keyboard message.

See also

• IKeyboardInputSink