atk/atkvalue.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 "atkvalue.h"
  21
  22 GType
  23 atk_value_get_type ()
  24 {
  25   static GType type = 0;
  26
  27   if (!type) {
  28     GTypeInfo tinfo =
  29     {
  30       sizeof (AtkValueIface),
  31       NULL,
  32       NULL,
  33
  34     };
  35
  36     type = g_type_register_static (G_TYPE_INTERFACE, "AtkValue", &tinfo, 0);
  37   }
  38
  39   return type;
  40 }
  41
  42 /**
  43  * atk_value_get_current_value:
  44  * @obj@: a GObject instance that implements AtkValueIface
  45  * @value: a #GValue representing the current accessible value
  46  *
  47  * WARNING: callers should not rely on %NULL or on a zero value for
  48  * indication of whether AtkValue is implemented, they should
  49  * use type checking/interface checking macros or the
  50  * atk_get_accessible_value() convenience method.
  51  **/
  52 void
  53 atk_value_get_current_value (AtkValue *obj,
  54                              GValue   *value)
  55 {
  56   AtkValueIface *iface;
  57
  58   g_return_if_fail (obj != NULL);
  59   g_return_if_fail (value != NULL);
  60   g_return_if_fail (ATK_IS_VALUE (obj));
  61
  62   iface = ATK_VALUE_GET_IFACE (obj);
  63
  64   if (iface->get_current_value)
  65     (iface->get_current_value) (obj, value);
  66 }
  67
  68 /**
  69  * atk_value_get_maximum_value:
  70  * @obj: a GObject instance that implements AtkValueIface
  71  * @value: a #GValue representing the maximum accessible value
  72  *
  73  * WARNING: callers should not rely on %NULL or on a zero value for
  74  * indication of whether AtkValue is implemented, they should
  75  * use type checking/interface checking macros or the
  76  * atk_get_accessible_value() convenience method.
  77  **/
  78 void
  79 atk_value_get_maximum_value  (AtkValue *obj,
  80                               GValue   *value)
  81 {
  82   AtkValueIface *iface;
  83
  84   g_return_if_fail (obj != NULL);
  85   g_return_if_fail (value != NULL);
  86   g_return_if_fail (ATK_IS_VALUE (obj));
  87
  88   iface = ATK_VALUE_GET_IFACE (obj);
  89
  90   if (iface->get_maximum_value)
  91     (iface->get_maximum_value) (obj, value);
  92 }
  93
  94 /**
  95  * atk_value_get_minimum_value:
  96  * @obj: a GObject instance that implements AtkValueIface
  97  * @value: a #GValue representing the minimum accessible value
  98  *
  99  * WARNING: callers should not rely on %NULL or on a zero value for
 100  * indication of whether AtkValue is implemented, they should
 101  * use type checking/interface checking macros or the
 102  * atk_get_accessible_value() convenience method.
 103  **/
 104 void
 105 atk_value_get_minimum_value (AtkValue *obj,
 106                              GValue   *value)
 107 {
 108   AtkValueIface *iface;
 109
 110   g_return_if_fail (obj != NULL);
 111   g_return_if_fail (value != NULL);
 112   g_return_if_fail (ATK_IS_VALUE (obj));
 113
 114   iface = ATK_VALUE_GET_IFACE (obj);
 115
 116   if (iface->get_minimum_value)
 117     return (iface->get_minimum_value) (obj, value);
 118 }
 119
 120 /**
 121  * atk_value_set_current_value:
 122  * @obj: a GObject instance that implements AtkValueIface
 123  * @value: a #GValue which is the desired new accessible value.
 124  * @return: %true if new value is successfully set, %false otherwise.
 125  **/
 126 gboolean
 127 atk_value_set_current_value (AtkValue *obj,
 128                              GValue   *value)
 129 {
 130   AtkValueIface *iface;
 131
 132   g_return_val_if_fail (obj != NULL, FALSE);
 133   g_return_val_if_fail (value != NULL, FALSE);
 134   g_return_val_if_fail (ATK_IS_VALUE (obj), FALSE);
 135   g_return_val_if_fail (G_IS_VALUE (value), FALSE);
 136
 137   iface = ATK_VALUE_GET_IFACE (obj);
 138
 139   if (iface->set_current_value)
 140     return (iface->set_current_value) (obj, value);
 141   else
 142     return FALSE;
 143 }