calling gdk_x11_drawable_get_xid() causes corruption with button_press_event handler

[Eigo Mori <eigom pop01 odn ne jp>]

Hi,

I am having trouble to catch button_press_event on gtk_drawing_area correctly after calling 
gdk_x11_drawable_get_xid() for the drawing_areas.

Please find the sample code below. It packs 10 drawing_area and set event handlers. When you click on the 
drawing_area, it prints out which drawing_area has been clicked. (i.e. 0-9)

This seems to work as I hope if I don't call gdk_x11_drawable_get_xid(). If I call 
gdk_x11_drawable_get_xid(), it reports correct number firstly but keep printing out the same number even if I 
click on the different drawing_area later. XID itself seems to be collected correctly.

This does not seem to occur with gtk+-2.18.0 or earlier but occurs with gtk+-2.18.1 or later.

It is quite possible that my code is wrong and was working by luck. But I couldn't find the right way after 
some struggling... I will appreciate if someone can kindly educate me.

-----
/*
  xid_test.c
  gcc -g -Wall `pkg-config --cflags --libs gtk+-2.0 gdk-2.0` -o xid_test xid_test.c
 */

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

GtkWidget *hbox, *window, *drawing_area[10];
GMainLoop *loop;
gulong xid[10];

static void
click_handler( GtkWidget *widget, GdkEventButton *event, int* p )
{
  g_printerr( "%dth icon clicked\n", *p );
}


static void
expose_handler( GtkWidget *widget, GdkEventButton *event, int* p )
{

  /*
  xid[*p] = gdk_x11_drawable_get_xid( widget->window );
  g_printerr( "getting xid for %dth icon : %ld\n", *p, xid[*p] );
  */
  gdk_draw_arc( widget->window,
                widget->style->fg_gc[GTK_WIDGET_STATE( widget )],
                TRUE,
                0, 
                0, 
                widget->allocation.width,
                widget->allocation.height,
                0, 
                64*36*(*p+1)
                );
}

int
main(int argc, char *argv[])
{
  int i;
  int id[10] = {0,1,2,3,4,5,6,7,8,9};

  gtk_init(&argc, &argv);

  hbox = gtk_hbox_new(FALSE,0);
  window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  gtk_widget_set_usize( window, 600, 50 );
  gtk_container_add(GTK_CONTAINER(window), hbox);

  for(i=0;i<10;i++){
    drawing_area[i] = gtk_drawing_area_new();
    gtk_signal_connect(GTK_OBJECT(drawing_area[i]), 
                       "button_press_event", GTK_SIGNAL_FUNC(click_handler), &id[i] );
    gtk_signal_connect(GTK_OBJECT(drawing_area[i]), 
                       "expose_event", GTK_SIGNAL_FUNC(expose_handler), &id[i] );
    gtk_widget_set_events(drawing_area[i], GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK);
    gtk_drawing_area_size(GTK_DRAWING_AREA(drawing_area[i]), 50, 50 );
    gtk_box_pack_start(GTK_BOX(hbox), drawing_area[i], FALSE, FALSE, 2);
  }

  gtk_widget_show( hbox );
  for(i=0;i<10;i++){
    gtk_widget_show(drawing_area[i]);
  }
  gtk_widget_show( window );

  for(i=0;i<10;i++){
  /* 
     seems that it does not matter whether you get xid here
     or in expose handler
  */
  /*  works if you comment it out  */
    xid[i] = gdk_x11_drawable_get_xid( drawing_area[i]->window );

    g_printerr( "getting xid for %dth icon : %ld\n", i, xid[i] );
  }

  loop = g_main_loop_new (NULL, FALSE);
  g_main_loop_run( loop );

  exit( 0 );
}
-----

Regards,
Eigo