Re: _NET_WM_USER_TIME reconsidered

[Matthias Clasen <mclasen redhat com>]

On Tue, 2006-09-26 at 17:58 +0200, Lubos Lunak wrote:
> Dne úterý 26 září 2006 12:21 Bill Haneman napsal(a):
> > Matthias/All:
> >
> > The whole _NET_WM_USER_TIME thing is a continuing problem for
> > accessibility, as it now stands.  In an assistive technology setting,
> > there isn't always an X event that corresponds to the "user action"
> > which results in a new window being posted or focus changing.  Since X
> > doesn't allow us to get a meaningful answer to "what's the current
> > timestamp", we have serious problems when trying to interact with
> > windows via non-X-device-based user requests.
> >
> > We really need a solution for this!
> 
>  Copy&paste from KApplication::updateUserTimestamp():
> 
> // get current X timestamp
> Window w = XCreateSimpleWindow( qt_xdisplay(), qt_xrootwin(), 0, 0, 1, 1, 0, 
> 0, 0 );
> XSelectInput( qt_xdisplay(), w, PropertyChangeMask );
> unsigned char data[ 1 ];
> XChangeProperty( qt_xdisplay(), w, XA_ATOM, XA_ATOM, 8, PropModeAppend, data, 
> 1 );
> XEvent ev;
> XWindowEvent( qt_xdisplay(), w, PropertyChangeMask, &ev );
> time = ev.xproperty.time;
> XDestroyWindow( qt_xdisplay(), w );
> 

Here is the gdk equivalent:

guint32
gdk_x11_get_server_time (GdkWindow *window)
{
  Display *xdisplay;
  Window   xwindow;
  guchar c = 'a';
  XEvent xevent;
  Atom timestamp_prop_atom;
  g_return_val_if_fail (GDK_IS_WINDOW (window), 0);
  g_return_val_if_fail (!GDK_WINDOW_DESTROYED (window), 0);
  xdisplay = GDK_WINDOW_XDISPLAY (window);
  xwindow = GDK_WINDOW_XWINDOW (window);
  timestamp_prop_atom =
    gdk_x11_get_xatom_by_name_for_display (GDK_WINDOW_DISPLAY (window),
                                           "GDK_TIMESTAMP_PROP");
  XChangeProperty (xdisplay, xwindow, timestamp_prop_atom,
                   timestamp_prop_atom,
                   8, PropModeReplace, &c, 1);
  XIfEvent (xdisplay, &xevent,
            timestamp_predicate, GUINT_TO_POINTER(xwindow));
  return xevent.xproperty.time;
}

it is even exported, so you can just use it.