atk/atkutil.c

   1 /* ATK -  Accessibility Toolkit
   2  * Copyright 2001 Sun Microsystems Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include "atkutil.h"
  21
  22 /*
  23  * This file supports the addition and removal of multiple focus handlers
  24  * as long as they are all called in the same thread.
  25  */
  26 static AtkFocusTrackerInit  focus_tracker_init = NULL;
  27
  28 static gboolean init_done = FALSE;
  29
  30 /*
  31  * Array of FocusTracker structs
  32  */
  33 static GArray *trackers = NULL;
  34 static guint  index = 0;
  35
  36 struct _FocusTracker {
  37   guint index;
  38   AtkFocusTracker func;
  39 };
  40 typedef struct _FocusTracker FocusTracker;
  41
  42 void
  43 atk_focus_tracker_init (AtkFocusTrackerInit    init)
  44 {
  45   if (focus_tracker_init == NULL)
  46     focus_tracker_init = init;
  47 }
  48
  49 guint
  50 atk_add_focus_tracker (AtkFocusTracker   focus_tracker)
  51 {
  52   g_return_val_if_fail ((focus_tracker != NULL), 0);
  53
  54   if (!init_done)
  55   {
  56     if (focus_tracker_init != NULL)
  57     {
  58       focus_tracker_init ();
  59     }
  60     trackers = g_array_sized_new (FALSE, TRUE, sizeof (FocusTracker), 0);
  61     init_done = TRUE;
  62   }
  63   if (init_done)
  64   {
  65     FocusTracker item;
  66
  67     item.index = ++index;
  68     item.func = focus_tracker;
  69     trackers = g_array_append_val (trackers, item);
  70     return index;
  71   }
  72   else
  73   {
  74     return 0;
  75   }
  76 }
  77
  78 void
  79 atk_remove_focus_tracker (guint            tracker_id)
  80 {
  81   FocusTracker *item;
  82   guint i;
  83
  84   if (trackers == NULL)
  85     return;
  86
  87   if (tracker_id == 0)
  88     return;
  89
  90   for (i = 0; i < trackers->len; i++)
  91   {
  92     item = &g_array_index (trackers, FocusTracker, i);
  93     if (item->index == tracker_id)
  94     {
  95       trackers = g_array_remove_index (trackers, i);
  96       break;
  97     }
  98   }
  99 }
 100
 101 void
 102 atk_focus_tracker_notify (AtkObject       *object)
 103 {
 104   FocusTracker *item;
 105   guint i;
 106
 107   if (trackers == NULL)
 108     return;
 109
 110   for (i = 0; i < trackers->len; i++)
 111   {
 112     item = &g_array_index (trackers, FocusTracker, i);
 113     g_return_if_fail (item != NULL);
 114     item->func (object);
 115   }
 116 }