/* ATK - Accessibility Toolkit
- * Copyright 2001 Sun Microsystems Inc.
+ * Copyright 2001, 2002, 2003 Sun Microsystems Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* Boston, MA 02111-1307, USA.
*/
+#include <string.h>
#include "atkvalue.h"
+/**
+ * SECTION:atkvalue
+ * @Short_description: The ATK interface implemented by valuators and
+ * components which display or select a value from a bounded range of
+ * values.
+ * @Title:AtkValue
+ *
+ * #AtkValue should be implemented for components which either display
+ * a value from a bounded range, or which allow the user to specify a
+ * value from a bounded range, or both. For instance, most sliders
+ * and range controls, as well as dials, should have #AtkObject
+ * representations which implement #AtkValue on the component's
+ * behalf. #AtKValues may be read-only, in which case attempts to
+ * alter the value return FALSE to indicate failure.
+ */
+
GType
-atk_value_get_type ()
+atk_value_get_type (void)
{
static GType type = 0;
* @obj: a GObject instance that implements AtkValueIface
* @value: a #GValue representing the current accessible value
*
- * Gets the value of this object
- * Note: callers should not rely on %NULL or on a zero value for
- * indication of whether AtkValue is implemented, they should
- * use type checking/interface checking macros or the
- * atk_get_accessible_value() convenience method.
+ * Gets the value of this object.
**/
void
atk_value_get_current_value (AtkValue *obj,
{
AtkValueIface *iface;
- g_return_if_fail (obj != NULL);
g_return_if_fail (value != NULL);
g_return_if_fail (ATK_IS_VALUE (obj));
iface = ATK_VALUE_GET_IFACE (obj);
if (iface->get_current_value)
- (iface->get_current_value) (obj, value);
+ {
+ if (G_IS_VALUE (value))
+ g_value_unset (value);
+ else
+ memset (value, 0, sizeof (*value));
+
+ (iface->get_current_value) (obj, value);
+ }
}
/**
* @obj: a GObject instance that implements AtkValueIface
* @value: a #GValue representing the maximum accessible value
*
- * Gets the maximum value of this object
- * Note: callers should not rely on %NULL or on a zero value for
- * indication of whether AtkValue is implemented, they should
- * use type checking/interface checking macros or the
- * atk_get_accessible_value() convenience method.
+ * Gets the maximum value of this object.
**/
void
atk_value_get_maximum_value (AtkValue *obj,
{
AtkValueIface *iface;
- g_return_if_fail (obj != NULL);
g_return_if_fail (value != NULL);
g_return_if_fail (ATK_IS_VALUE (obj));
iface = ATK_VALUE_GET_IFACE (obj);
if (iface->get_maximum_value)
- (iface->get_maximum_value) (obj, value);
+ {
+ if (G_IS_VALUE (value))
+ g_value_unset (value);
+ else
+ memset (value, 0, sizeof (*value));
+
+ (iface->get_maximum_value) (obj, value);
+ }
}
/**
* @obj: a GObject instance that implements AtkValueIface
* @value: a #GValue representing the minimum accessible value
*
- * Gets the mimnimum value of this object
- * Note: callers should not rely on %NULL or on a zero value for
- * indication of whether AtkValue is implemented, they should
- * use type checking/interface checking macros or the
- * atk_get_accessible_value() convenience method.
+ * Gets the minimum value of this object.
**/
void
atk_value_get_minimum_value (AtkValue *obj,
{
AtkValueIface *iface;
- g_return_if_fail (obj != NULL);
g_return_if_fail (value != NULL);
g_return_if_fail (ATK_IS_VALUE (obj));
iface = ATK_VALUE_GET_IFACE (obj);
if (iface->get_minimum_value)
- (iface->get_minimum_value) (obj, value);
+ {
+ if (G_IS_VALUE (value))
+ g_value_unset (value);
+ else
+ memset (value, 0, sizeof (*value));
+
+ (iface->get_minimum_value) (obj, value);
+ }
+}
+
+/**
+ * atk_value_get_minimum_increment:
+ * @obj: a GObject instance that implements AtkValueIface
+ * @value: a #GValue representing the minimum increment by which the accessible value may be changed
+ *
+ * Gets the minimum increment by which the value of this object may be changed. If zero,
+ * the minimum increment is undefined, which may mean that it is limited only by the
+ * floating point precision of the platform.
+ *
+ * Since: 1.12
+ **/
+void
+atk_value_get_minimum_increment (AtkValue *obj,
+ GValue *value)
+{
+ AtkValueIface *iface;
+
+ g_return_if_fail (value != NULL);
+ g_return_if_fail (ATK_IS_VALUE (obj));
+
+ iface = ATK_VALUE_GET_IFACE (obj);
+
+ if (iface->get_minimum_increment)
+ {
+ if (G_IS_VALUE (value))
+ g_value_unset (value);
+ else
+ memset (value, 0, sizeof (*value));
+
+ (iface->get_minimum_increment) (obj, value);
+ }
}
/**
* @obj: a GObject instance that implements AtkValueIface
* @value: a #GValue which is the desired new accessible value.
*
- * Sets the value of this object
+ * Sets the value of this object.
*
* Returns: %TRUE if new value is successfully set, %FALSE otherwise.
**/
{
AtkValueIface *iface;
- g_return_val_if_fail (obj != NULL, FALSE);
- g_return_val_if_fail (value != NULL, FALSE);
g_return_val_if_fail (ATK_IS_VALUE (obj), FALSE);
g_return_val_if_fail (G_IS_VALUE (value), FALSE);