|
//---------------------------------------------------------------------------
//
// <copyright file="WindowHideOrCloseTracker.cs" company="Microsoft">
// Copyright (C) Microsoft Corporation. All rights reserved.
// </copyright>
//
//
// Description: Class used to track new UI appearing and make sure any events
// are propogated to that new UI.
//
// History:
// 11/20/2003 : Micw Created
//
//---------------------------------------------------------------------------
using System;
using System.Text;
using System.Windows.Automation;
using MS.Win32;
using System.Diagnostics;
namespace MS.Internal.Automation
{
// WindowHideOrCloseTracker - Class used to track new UI appearing and make sure any events
// are propogated to that new UI.
internal delegate void WindowHideOrCloseHandler( IntPtr hwnd, AutomationElement rawEl, int[] runtimeId );
// Class used to track new UI appearing and make sure any events
// are propogated to that new UI.
internal class WindowHideOrCloseTracker : WinEventWrap
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
internal WindowHideOrCloseTracker(WindowHideOrCloseHandler newUIHandler)
: base(new int[]
{NativeMethods.EVENT_OBJECT_DESTROY, NativeMethods.EVENT_OBJECT_HIDE})
{
AddCallback(newUIHandler);
}
#endregion Constructors
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
#region Internal Methods
internal override void WinEventProc(int eventId, IntPtr hwnd, int idObject, int idChild, uint eventTime)
{
// ignore any event not pertaining directly to the window
if (idObject != UnsafeNativeMethods.OBJID_WINDOW)
return;
// Ignore if this is a bogus hwnd (shouldn't happen)
if (hwnd == IntPtr.Zero)
return;
NativeMethods.HWND nativeHwnd = NativeMethods.HWND.Cast( hwnd );
// Purposefully including windows that have been destroyed (e.g. IsWindow will return
// false here for EVENT_OBJECT_DESTROY) because we need that notification.
if (eventId == NativeMethods.EVENT_OBJECT_HIDE && !SafeNativeMethods.IsWindow( nativeHwnd ))
{
return;
}
int[] runtimeId;
AutomationElement rawEl;
if (eventId == NativeMethods.EVENT_OBJECT_DESTROY)
{
// If the window has been destroyed just report the RuntimeId with the event.
runtimeId = HwndProxyElementProvider.MakeRuntimeId( nativeHwnd );
rawEl = null;
}
else
{
// If the window is just being hidden then can create (and return as event src) a real element
rawEl = AutomationElement.FromHandle( hwnd );
runtimeId = rawEl.GetRuntimeId();
}
// Do the notify. Note that this handler is used to notify client-side UIAutomation providers of windows
// being destroyed or hidden. The delegate called here is itself protected by a lock. This delegate may
// call out to proxies but also calls ClientEventManager.RaiseEventInThisClientOnly which properly
// queues the actual callout to client code.
object[] handlers = GetHandlers();
Debug.Assert(handlers.Length <= 1, "handlers.Length");
if ( handlers.Length > 0 )
( (WindowHideOrCloseHandler)handlers [0] )( hwnd, rawEl, runtimeId );
}
#endregion Internal Methods
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
// no state
#endregion Private Fields
}
}
|