atkcomponent.c

linux下图形库开发包atk-1.4.0.tar.gz

/* ATK -  Accessibility Toolkit
 * Copyright 2001 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
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */


#include "atkcomponent.h"

static void       atk_component_base_init (AtkComponentIface *class);

static gboolean   atk_component_real_contains                (AtkComponent *component,
                                                              gint         x,
                                                              gint         y,
                                                              AtkCoordType coord_type);

static AtkObject* atk_component_real_ref_accessible_at_point (AtkComponent *component,
                                                              gint         x,
                                                              gint         y,
                                                              AtkCoordType coord_type);

static void      atk_component_real_get_position             (AtkComponent *component,
                                                              gint         *x,
                                                              gint         *y,
                                                              AtkCoordType coord_type);

static void      atk_component_real_get_size                 (AtkComponent *component,
                                                              gint         *width,
                                                              gint         *height);

GType
atk_component_get_type (void)
{
  static GType type = 0;

  if (!type) {
    static const GTypeInfo tinfo =
    {
      sizeof (AtkComponentIface),
      (GBaseInitFunc) atk_component_base_init,
      (GBaseFinalizeFunc) NULL,

    };

    type = g_type_register_static (G_TYPE_INTERFACE, "AtkComponent", &tinfo, 0);
  }

  return type;
}

static void
atk_component_base_init (AtkComponentIface *class)
{
  static gboolean initialized = FALSE;

  if (! initialized)
    {
      class->ref_accessible_at_point = atk_component_real_ref_accessible_at_point;
      class->contains = atk_component_real_contains;
      class->get_position = atk_component_real_get_position;
      class->get_size = atk_component_real_get_size;
    }
}


/**
 * atk_component_add_focus_handler:
 * @component: The #AtkComponent to attach the @handler to
 * @handler: The #AtkFocusHandler to be attached to @component
 *
 * Add the specified handler to the set of functions to be called 
 * when this object receives focus events (in or out). If the handler is
 * already added it is not added again
 *
 * Returns: a handler id which can be used in atk_component_remove_focus_handler
 * or zero if the handler was already added.
 **/
guint
atk_component_add_focus_handler (AtkComponent    *component,
                                 AtkFocusHandler handler)
{
  AtkComponentIface *iface = NULL;
  g_return_val_if_fail (ATK_IS_COMPONENT (component), 0);

  iface = ATK_COMPONENT_GET_IFACE (component);

  if (iface->add_focus_handler)
    return (iface->add_focus_handler) (component, handler);
  else
    return 0;
}

/**
 * atk_component_remove_focus_handler:
 * @component: the #AtkComponent to remove the focus handler from
 * @handler_id: the handler id of the focus handler to be removed
 * from @component
 *
 * Remove the handler specified by @handler_id from the list of
 * functions to be executed when this object receives focus events 
 * (in or out).
 **/
void
atk_component_remove_focus_handler (AtkComponent    *component,
                                    guint           handler_id)
{
  AtkComponentIface *iface = NULL;
  g_return_if_fail (ATK_IS_COMPONENT (component));

  iface = ATK_COMPONENT_GET_IFACE (component);

  if (iface->remove_focus_handler)
    (iface->remove_focus_handler) (component, handler_id);
}

/**
 * atk_component_contains:
 * @component: the #AtkComponent
 * @x: x coordinate
 * @y: y coordinate
 * @coord_type: specifies whether the coordinates are relative to the screen
 * or to the components top level window
 *
 * Checks whether the specified point is within the extent of the @component.
 *
 * Returns: %TRUE or %FALSE indicating whether the specified point is within
 * the extent of the @component or not
 **/
gboolean
atk_component_contains (AtkComponent    *component,
                        gint            x,
                        gint            y,
                        AtkCoordType    coord_type)
{
  AtkComponentIface *iface = NULL;
  g_return_val_if_fail (ATK_IS_COMPONENT (component), FALSE);

  iface = ATK_COMPONENT_GET_IFACE (component);

  if (iface->contains)
    return (iface->contains) (component, x, y, coord_type);
  else
    return FALSE;
}

/**
 * atk_component_ref_accessible_at_point:
 * @component: the #AtkComponent
 * @x: x coordinate
 * @y: y coordinate
 * @coord_type: specifies whether the coordinates are relative to the screen
 * or to the components top level window
 *
 * Gets a reference to the accessible child, if one exists, at the
 * coordinate point specified by @x and @y.
 *
 * Returns: a reference to the accessible child, if one exists
 **/
AtkObject*
atk_component_ref_accessible_at_point (AtkComponent    *component,
                                       gint            x,
                                       gint            y,
                                       AtkCoordType    coord_type)
{
  AtkComponentIface *iface = NULL;
  g_return_val_if_fail (ATK_IS_COMPONENT (component), NULL);

  iface = ATK_COMPONENT_GET_IFACE (component);

  if (iface->ref_accessible_at_point)
    return (iface->ref_accessible_at_point) (component, x, y, coord_type);
  else
    return NULL;
}

/**
 * atk_component_get_extents:
 * @component: an #AtkComponent
 * @x: address of #gint to put x coordinate
 * @y: address of #gint to put y coordinate
 * @width: address of #gint to put width
 * @height: address of #gint to put height
 * @coord_type: specifies whether the coordinates are relative to the screen
 * or to the components top level window
 *
 * Gets the rectangle which gives the extent of the @component.
 *
 **/
void
atk_component_get_extents    (AtkComponent    *component,
                              gint            *x,
                              gint            *y,
                              gint            *width,
                              gint            *height,
                              AtkCoordType    coord_type)
{
  AtkComponentIface *iface = NULL;
  gint local_x, local_y, local_width, local_height;
  gint *real_x, *real_y, *real_width, *real_height;

  g_return_if_fail (ATK_IS_COMPONENT (component));

  if (x)
    real_x = x;
  else
    real_x = &local_x;
  if (y)
    real_y = y;
  else
    real_y = &local_y;
  if (width)
    real_width = width;
  else
    real_width = &local_width;
  if (height)
    real_height = height;
  else
    real_height = &local_height;

  iface = ATK_COMPONENT_GET_IFACE (component);

  if (iface->get_extents)
    (iface->get_extents) (component, real_x, real_y, real_width, real_height, coord_type);
}

/**
 * atk_component_get_position:
 * @component: an #AtkComponent
 * @x: address of #gint to put x coordinate position
 * @y: address of #gint to put y coordinate position
 * @coord_type: specifies whether the coordinates are relative to the screen
 * or to the components top level window
 *
 * Gets the position of @component in the form of 
 * a point specifying @component's top-left corner.
 **/
void
atk_component_get_position   (AtkComponent    *component,
                              gint            *x,
                              gint            *y,
                              AtkCoordType    coord_type)
{
  AtkComponentIface *iface = NULL;
  gint local_x, local_y;
  gint *real_x, *real_y;

  g_return_if_fail (ATK_IS_COMPONENT (component));

  if (x)
    real_x = x;
  else
    real_x = &local_x;
  if (y)
    real_y = y;
  else
    real_y = &local_y;

  iface = ATK_COMPONENT_GET_IFACE (component);

  if (iface->get_position)
    (iface->get_position) (component, real_x, real_y, coord_type);
}