// OnEventSystemCaptureEnd - process an EventSystemCaptureEnd WinEvent.
private void OnEventSystemCaptureEnd(int eventId, IntPtr hwnd, int idObject, int idChild, uint eventTime)
{
// Deal only with Combolbox dropdowns...
if (Accessible.IsComboDropdown(hwnd))
{
SafeNativeMethods.GUITHREADINFO guiThreadInfo = new SafeNativeMethods.GUITHREADINFO();
if (!Misc.GetGUIThreadInfo(0, ref guiThreadInfo))
{
return;
}
Accessible acc = Accessible.Create(guiThreadInfo.hwndFocus, UnsafeNativeMethods.OBJID_CLIENT, 0);
if (acc == null)
{
return;
}
HandleFocusChange(hwnd, acc, idObject, idChild, eventTime);
}
}
internal static bool GetGUIThreadInfo(int idThread, ref SafeNativeMethods.GUITHREADINFO guiThreadInfo)
{
guiThreadInfo.cbSize = Marshal.SizeOf(guiThreadInfo);
bool result = SafeNativeMethods.GetGUIThreadInfo(0, ref guiThreadInfo);
int lastWin32Error = Marshal.GetLastWin32Error();
if (!result)
{
// If the focused thread is on another [secure] desktop, GetGUIThreadInfo
// will fail with ERROR_ACCESS_DENIED - don't throw an exception for that case,
// instead treat as a failure. Callers will treat this as though no window has
// focus.
if (lastWin32Error == 5 /*ERROR_ACCESS_DENIED*/)
{
return(false);
}
ThrowWin32ExceptionsIfError(lastWin32Error);
}
return(result);
}
