How can we get information about a focused widget in another GTK application?

["samereberlin gmail com" <samereberlin gmail com>]

Hi all,

    How can we get information (type, status and label) about a focused
widget in another GTK application?  (The “gtk_window_get_focus” and
“GTK_WIDGET_TYPE” would be usefull only if we could get a pointer to
this “another” GtkWindow, but I think it's not possible).

    Obviously, the another GTK application must be the top level of the
current screen, and I think that, to work (and interact) with another
top level application, is possible only using GDK (or Xlib) resources.
Then I wrote the following code (see below), but (for the time being) it
gives us only the name of the top level (focused) application, and I
would like to reach the focused widget information too.

    The reason: I'd like to reach those informations to drive (help by
audio returns) the user actions in this another application, cause I'll
start (or at least I'll try a lot) to work on a Screen Reader project.

Thanks very much,
Samer Eberlin.

/* = = = = = = = = = = = = Start Code = = = = = = = = = = = = = = = = */

#include <gtk/gtk.h>
#include <gdk/gdkx.h>

/**********************************************************************/
/* Main function: *****************************************************/
/**********************************************************************/
int main (int argc, char *argv[])
{
    /* Function prototypes */
    void GetWin (Window*);

    /* Variables */
    Window toplevel;
    XEvent ev;

    /* GDK init */
    gtk_init (&argc, &argv);

    /* GetWin function */
    GetWin (&toplevel);

    /* Main Loop */
    while (1)
    {
        XNextEvent (GDK_DISPLAY(), &ev);
        switch (ev.type)
        {
            case FocusOut:
                GetWin (&toplevel);
                break;
            default:
                break;
        }
    }
    return 0;
}

/**********************************************************************/
/* GetWin: gets the focused window: ***********************************/
/**********************************************************************/
void GetWin (Window *toplevel)
{
    /* Variables */
    Window win, focwin, root, parent, *children;
    int focus; unsigned int nchildren;
    GtkWidget *dialog;
    XClassHint ch;
        ch.res_name = NULL;
        ch.res_class = NULL;

    /* XGet functions */
    XGetInputFocus (GDK_DISPLAY(), &focwin, &focus);
    XGetClassHint (GDK_DISPLAY(), focwin, &ch);
    if (ch.res_class != NULL)
        win = focwin;
    else
    {
        XQueryTree (GDK_DISPLAY(), focwin, &root, &parent,
                    &children, &nchildren);
        XFree (children);
        XGetClassHint (GDK_DISPLAY(), parent, &ch);
        win = parent;
    }

    /* Focus change */
    if (win != *toplevel)
    {
        printf ("The focused window's name is: \"%s\"\n", ch.res_class);
        dialog = gtk_message_dialog_new (NULL, GTK_DIALOG_MODAL,
                                         GTK_MESSAGE_INFO,
                                         GTK_BUTTONS_CLOSE,
                                         ch.res_class);
        gtk_dialog_run (GTK_DIALOG (dialog));
        gtk_widget_destroy (dialog);
        XSelectInput (GDK_DISPLAY(), win, FocusChangeMask);
        *toplevel = win;
    }
}

/* = = = = = = = = = = = = End Code = = = = = = = = = = = = = = = = = */