path: root/atk/atkobject.h

/* 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 Library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library 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.
 */

#ifndef __ATK_OBJECT_H__
#define __ATK_OBJECT_H__

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

#include <glib-object.h>

/*
 * AtkObject represents the minimum information all accessible objects
 * return. This information includes accessible name, accessible
 * description, role and state of the object, as well information about
 * its parent and children. It is also possible to obtain more specific
 * accessibility information about a component if it supports one or more
 * of the following interfaces:
 */
typedef enum
{
  ATK_CHILD_ADDED,
  ATK_CHILD_REMOVED,
  ATK_CHILD_CHANGED
} AtkChildChangeType;

typedef enum
{
  ATK_ROLE_INVALID,
  /* Object is used to alert the user about something */
  ATK_ROLE_ALERT,
  /* Object that can be drawn into and is sued to trap events */
  ATK_ROLE_CANVAS,
  /*
   * A choice that can be checked or unchecked and provides a separate
   * indicator for the current state.
   */
  ATK_ROLE_CHECK_BOX,
  /* A specialized dialog that lets the user choose a color. */
  ATK_ROLE_COLOR_CHOOSER,
  /* The header for a column of data */
  ATK_ROLE_COLUMN_HEADER,
  /* A list of choices the user can select from */
  ATK_ROLE_COMBO_BOX,
  /* An inconifed internal frame within a DESKTOP_PANE */
  ATK_ROLE_DESKTOP_ICON,
  /*
   * A pane that supports internal frames and iconified versions of those
   * internal frames.
   */
  ATK_ROLE_DESKTOP_FRAME,
  /* A top level window with title bar and a border */
  ATK_ROLE_DIALOG,
  /*
   * A pane that allows the user to navigate through and select the contents
   * of a directory
   */
  ATK_ROLE_DIRECTORY_PANE,
  /*
   * A specialized dialog that displays the files in the directory and lets
   * the user select a file, browse a different directory, or specify a
   * filename.
   */
  ATK_ROLE_FILE_CHOOSER,
  /*
   * A object that fills up space in a user interface
   */
  ATK_ROLE_FILLER,
  /* XXX Don't know sure about this. */
  ATK_ROLE_FOCUS_TRAVERSABLE,
  /* A top level window with a title bar, border, menubar, etc. */
  ATK_ROLE_FRAME,
  /* A pane that is guaranteed to be painted on top of all panes beneath it */
  ATK_ROLE_GLASS_PANE,
  /*
   * A document container for HTML, whose children
   * represent the document content.
   */
  ATK_ROLE_HTML_CONTAINER,
  /* A small fixed size picture, typically used to decorate components */
  ATK_ROLE_ICON,
  /* A frame-like object that is clipped by a desktop pane. */
  ATK_ROLE_INTERNAL_FRAME,
  /* An object used to present an icon or short string in an interface */
  ATK_ROLE_LABEL,
  /*
   * A specialized pane that allows its children to be drawn in layers,
   * providing a form of stacking order.
   */
  ATK_ROLE_LAYERED_PANE,
  /*
   * An object that presents a list of objects to the user and allows the
   * user to select one or more of them.
   */
  ATK_ROLE_LIST,
   /* An object that represents an element of a list. */
  ATK_ROLE_LIST_ITEM,
  /*
   * An object usually found inside a menu bar that contains a list of
   * actions the user can choose from.
   */
  ATK_ROLE_MENU,
  /*
   * An object usually drawn at the top of the primary dialog box of an
   * application that contains a list of menus the user can choose from.
   */
  ATK_ROLE_MENU_BAR,
  /*
   * An object usually contained in a menu that presents an action the
   * user can choose.
   */
  ATK_ROLE_MENU_ITEM,
  /* A specialized pane whose primary use is inside a DIALOG */
  ATK_ROLE_OPTION_PANE,
  /* An object that is a child of a page tab list */
  ATK_ROLE_PAGE_TAB,
  /*
   * An object that presents a series of panels (or page tabs), one at a time,
   * through some mechanism provided by the object.
   */
  ATK_ROLE_PAGE_TAB_LIST,
  /* A generic container that is often used to group objects. */
  ATK_ROLE_PANEL,
  /*
   * A text object uses for passwords, or other places where the text
   * content is not shown visibly to the user.
   */
  ATK_ROLE_PASSWORD_TEXT,
  /*
   * A temporary window that is usually used to offer the user a list of
   * choices, and then hides when the user selects one of those choices.
   */
  ATK_ROLE_POPUP_MENU,
  /* An object used to indicate how much of a task has been completed. */
  ATK_ROLE_PROGRESS_BAR,
  /*
   * An object the user can manipulate to tell the application to do
   * something.
   */
  ATK_ROLE_PUSH_BUTTON,
  /*
   * A specialized check box that will cause other radio buttons in the
   * same group to become uncghecked when this one is checked.
   */
  ATK_ROLE_RADIO_BUTTON,
  /*
   * A specialized pane that has a glass pane and a layered pane as its
   * children.
   */
  ATK_ROLE_ROOT_PANE,
  /* The header for a row of data */
  ATK_ROLE_ROW_HEADER,
  /*
   * An object usually used to allow a user to incrementally view a large
   * amount of data.
   */
  ATK_ROLE_SCROLL_BAR,
  /*
   * An object that allows a user to incrementally view a large amount
   * of information.
   */
  ATK_ROLE_SCROLL_PANE,
  /*
   * An object usually contained in a menu to provide a visible and
   * logical separation of the contents in a menu.
   */
  ATK_ROLE_SEPARATOR,
  /* An object that allows the user to select from a bounded range */
  ATK_ROLE_SLIDER,
  /* A specialized panel that presents two other panels at the same time. */
  ATK_ROLE_SPLIT_PANE,
  /* An object used to rpesent information in terms of rows and columns. */
  ATK_ROLE_TABLE,
  ATK_ROLE_TABLE_CELL,
  ATK_ROLE_TABLE_COLUMN_HEADER,
  ATK_ROLE_TABLE_ROW_HEADER,
  /* An object that presents text to the user */
  ATK_ROLE_TEXT,
  /*
   * A specialized push button that can be checked or unchecked, but does
   * not procide a separate indicator for the current state.
   */
  ATK_ROLE_TOGGLE_BUTTON,
  /*
   * A bar or palette usually composed of push buttons or toggle buttons
   */
  ATK_ROLE_TOOL_BAR,
  /*
   * An object that provides information about another object
   */
  ATK_ROLE_TOOL_TIP,
  /* An object used to repsent hierarchical information to the user. */
  ATK_ROLE_TREE,
  /*
   * The object contains some Accessible information, but its role is
   * not known.
   */
  ATK_ROLE_UNKNOWN,
  /* An object usually used in a scroll pane. */
  ATK_ROLE_VIEWPORT,
  /* A top level window with no title or border */
  ATK_ROLE_WINDOW,
  /* not a valid role, used for finding end of enumeration. */
  ATK_ROLE_LAST_DEFINED
} AtkRole;

AtkRole                  atk_role_register        (gchar *name);

typedef enum
{
  ATK_STATE_INVALID,
  /* Indicates a window is currently the active window */
  ATK_STATE_ACTIVE,
  /* Indicates that the object is armed */
  ATK_STATE_ARMED,
  /* Indicates the current object is busy */
  ATK_STATE_BUSY,
  /* Indicates this object is currently checked */
  ATK_STATE_CHECKED,
  /* Indicates this object is collapsed */
  ATK_STATE_COLLAPSED,
  /* Indicates the user can change the contents of this object */
  ATK_STATE_EDITABLE,
  /* Indicates this object allows progressive disclosure of its children */
  ATK_STATE_EXPANDABLE,
  /* Indicates this object its expanded */
  ATK_STATE_EXPANDED,
  /*
   * Indicates this object can accept keyboard focus, which means all
   * events resulting from typing on the keyboard will normally be passed
   * to it when it has focus
   */
  ATK_STATE_FOCUSABLE,
  /* Indicates this object currently has the keyboard focus */
  ATK_STATE_FOCUSED,
  /* Indicates the orientation of thsi object is horizontal */
  ATK_STATE_HORIZONTAL,
  /* Indicates this object is minimized and is represented only by an icon */
  ATK_STATE_ICONIFIED,
  /*
   * Indicates something must be done with this object before the user can
   * interact with an object in a different window.
   */
  ATK_STATE_MODAL,
  /* Indicates this (text) object can contain multiple lines of text */
  ATK_STATE_MULTI_LINE,
  /*
   * Indicates this object allows more than one of its children to be
   * selected at the same time
   */
  ATK_STATE_MULTISELECTABLE,
  /* Indicates this object paints every pixel within its rectangular region. */
  ATK_STATE_OPAQUE,
  /* Indicates this object is currently pressed */
  ATK_STATE_PRESSED,
  /* Indicates the size of this object is not fixed */
  ATK_STATE_RESIZABLE,
  /*
   * Indicates this object is the child of an object that allows its
   * children to be selected and that this child is one of those children
   * that can be selected.
   */
  ATK_STATE_SELECTABLE,
  /*
   * Indicates this object is the child of an object that allows its
   * children to be selected and that this child is one of those children
   * that has been selected.
   */
  ATK_STATE_SELECTED,
  /* Indicates this object is sensitive */
  ATK_STATE_SENSITIVE,
  /*
   * Indicates this object, the object's parent, the object's parent's
   * parent, and so on, are all visible
   */
  ATK_STATE_SHOWING,
  /* Indicates this (text) object can contain only a single line of text */
  ATK_STATE_SINGLE_LINE,
  /* Indicates this object is transient */
  ATK_STATE_TRANSIENT,
  /* Indicates the orientation of this object is vertical */
  ATK_STATE_VERTICAL,
  /* Indicates this object is visible */
  ATK_STATE_VISIBLE,
  ATK_STATE_LAST_DEFINED
} AtkStateType;

AtkStateType               atk_state_type_register      (gchar *name);


#define ATK_TYPE_OBJECT                           (atk_object_get_type ())
#define ATK_OBJECT(obj)                           (G_TYPE_CHECK_INSTANCE_CAST ((obj), ATK_TYPE_OBJECT, AtkObject))
#define ATK_OBJECT_CLASS(klass)                   (G_TYPE_CHECK_CLASS_CAST ((klass), ATK_TYPE_OBJECT, AtkObjectClass))
#define ATK_IS_OBJECT(obj)                        (G_TYPE_CHECK_INSTANCE_TYPE ((obj), ATK_TYPE_OBJECT))
#define ATK_IS_OBJECT_CLASS(klass)                (G_TYPE_CHECK_CLASS_TYPE ((klass), ATK_TYPE_OBJECT))
#define ATK_OBJECT_GET_CLASS(obj)                 (G_TYPE_INSTANCE_GET_CLASS ((obj), ATK_TYPE_OBJECT, AtkObjectClass))

#define ATK_TYPE_OBJECT_IFACE                     (atk_object_iface_get_type ())
#define ATK_OBJECT_GET_IFACE(obj)                 (G_TYPE_INSTANCE_GET_INTERFACE ((obj), ATK_TYPE_OBJECT_IFACE, AtkObjectIface))


/* Forward declarations of interface structures */

typedef struct _AtkIfaceImplementor               AtkIfaceImplementor;

typedef struct _AtkObjectIface                    AtkObjectIface;

typedef struct _AtkActionIface                    AtkActionIface;
typedef struct _AtkComponentIface                 AtkComponentIface;
typedef struct _AtkEditableTextIface              AtkEditableTextIface;
typedef struct _AtkHypertextIface                 AtkHypertextIface;
typedef struct _AtkImageIface                     AtkImageIface;
typedef struct _AtkSelectionIface                 AtkSelectionIface;
typedef struct _AtkTableIface                     AtkTableIface;
typedef struct _AtkTextIface                      AtkTextIface;
typedef struct _AtkValueIface                     AtkValueIface;


typedef struct _AtkObject                         AtkObject;
typedef struct _AtkObjectClass                    AtkObjectClass;
typedef struct _AtkRelation                       AtkRelation;
typedef struct _AtkRelationSet                    AtkRelationSet;

typedef guint64                                 AtkStateMask;
typedef guint64                                 AtkState;

#define ATK_STATE(state_enum)                   ((AtkStateMask)(1 << ((guint64)(state_enum)%64)))

struct _AtkPropertyValues
{
  gchar  *property_name;
  GValue old_value;
  GValue new_value;
};

typedef struct _AtkPropertyValues                AtkPropertyValues;

/*
 * For most properties the old_value field of AtkPropertyValues will
 * not contain a valid value.
 *
 * Currently, the only property for which old_value is used is
 * accessible-state; for instance if there is a focus state the
 * property change handler will be called for the object which lost the focus
 * with the old_value containing an AtkState value corresponding to focused
 * and the property change handler will be called for the object which
 * received the focus with the new_value containing an AtkState value
 * corresponding to focused.
 */
typedef void (*AtkPropertyChangeHandler) (AtkObject*, AtkPropertyValues*);


struct _AtkObject
{
  GObject parent;

  gchar *description;
  gchar *name;
  AtkObject *accessible_parent;
  AtkRole role;
  AtkRelationSet *relation_set;
};

struct _AtkObjectClass
{
  GObjectClass parent;

  /*
   * Gets the accessible name of the object
   */
  G_CONST_RETURN gchar*    (* get_name)            (AtkObject                *accessible);
  /*
   * Gets the accessible description of the object
   */
  G_CONST_RETURN gchar*    (* get_description)     (AtkObject                *accessible);
  /*
   * Gets the accessible parent of the object
   */
  AtkObject*               (*get_parent)           (AtkObject                *accessible);

  /*
   * Gets the number of accessible children of the object
   */
  gint                    (* get_n_children)       (AtkObject                *accessible);
  /*
   * Returns a reference to the specified accessible child of the object.
   * The accessible children are 0-based so the first accessible child is
   * at index 0, the second at index 1 and so on.
   */
  AtkObject*              (* ref_child)            (AtkObject                *accessible,
                                                    gint                      i);
  /*
   * Gets the 0-based index of this object in its parent; returns -1 if the
   * object does not have an accessible parent.
   */
  gint                    (* get_index_in_parent) (AtkObject                 *accessible);
  /*
   * Gets the RelationSet associated with the object
   */
  AtkRelationSet*         (* get_relation_set)    (AtkObject                 *accessible);
  /*
   * Gets the role of the object
   */
  AtkRole                 (* get_role)            (AtkObject                 *accessible);
  /*
   * Gets the state set of the object
   */
  AtkState                (* get_state)           (AtkObject                 *accessible);
  /*
   * Sets the accessible name of the object
   */
  void                    (* set_name)            (AtkObject                 *accessible,
                                                   const gchar               *name);
  /*
   * Sets the accessible description of the object
   */
  void                    (* set_description)     (AtkObject                 *accessible,
                                                   const gchar               *description);
  /*
   * Sets the accessible parent of the object
   */
  void                    (* set_parent)          (AtkObject                 *accessible,
                                                   AtkObject                 *parent);
  /*
   * Sets the accessible role of the object
   */
  void                    (* set_role)            (AtkObject                 *accessible,
                                                   AtkRole                   role);
  /*
   * Specifies a function to be called when a property changes value
   */
guint                     (* connect_property_change_handler)    (AtkObject
                 *accessible,
                                                                  AtkPropertyChangeHandler       *handler);
  /*
   * Removes a property change handler which was specified using
   * connect_property_change_handler
   */
void                      (* remove_property_change_handler)     (AtkObject
                *accessible,
                                                                  guint
                handler_id);
  /*
   * The signal handler which is executed when there is a change in the
   * children of the object
   */
  void                    (* children_changed)    (AtkObject                  *accessible,
                                                   AtkChildChangeType         change_type,
                                                   AtkObject                  *changed_child);
};
GType            atk_object_get_type   (void);

struct _AtkObjectIface
{
  GTypeInterface parent;

  AtkObject*   (*ref_accessible) (AtkIfaceImplementor *accessible);
};
GType atk_object_iface_get_type (void);

/*
 * This method uses the ref_accessible method in AtkObjectIface,
 * if the object's class implements AtkObjectIface.
 * Otherwise it returns %NULL.
 *
 * IMPORTANT:
 * Note also that because this method may return flyweight objects,
 * it increments the returned AtkObject's reference count.
 * Therefore it is the responsibility of the calling
 * program to unreference the object when no longer needed.
 * (c.f. gtk_widget_get_accessible() where this is not the case).
 */
AtkObject*              atk_object_ref_accessible                 (AtkIfaceImplementor *accessible);

/*
 * Properties directly supported by AtkObject
 */

G_CONST_RETURN gchar*   atk_object_get_name                       (AtkObject *accessible);
G_CONST_RETURN gchar*   atk_object_get_description                (AtkObject *accessible);
AtkObject*              atk_object_get_parent                     (AtkObject *accessible);
gint                    atk_object_get_n_accessible_children      (AtkObject *accessible);
AtkObject*              atk_object_ref_accessible_child           (AtkObject *accessible,
                                                                   gint        i);
AtkRelationSet*         atk_object_get_relation_set               (AtkObject *accessible);
AtkRole                 atk_object_get_role                       (AtkObject *accessible);
AtkState                atk_object_get_state                      (AtkObject *accessible);
gint                    atk_object_get_index_in_parent            (AtkObject *accessible);
void                    atk_object_set_name                       (AtkObject *accessible,
                                                                   const gchar *name);
void                    atk_object_set_description                (AtkObject *accessible,
                                                                   const gchar *description);
void                    atk_object_set_parent                     (AtkObject *accessible,
                                                                   AtkObject *parent);
void                    atk_object_set_role                       (AtkObject *accessible,
                                                                   AtkRole   role);


/*
 * to install property change listener, one must
 * install signal handler for gobject "properties_changed" signal.
 * (for single notifications of multiple changes).
 * We could use the "notify" signal instead.
 *
 */
guint                atk_object_connect_property_change_handler  (AtkObject                      *accessible,
                                                                  AtkPropertyChangeHandler       *handler);
void                 atk_object_remove_property_change_handler  (AtkObject                      *accessible,
                                                                  guint                         handler_id);

/*
 * Note: the properties which are registered with the GType
 *   property registry, for type ATK_TYPE_OBJECT, are as follows:
 *
 *   "accessible-name"
 *   "accessible-description"
 *   "accessible-parent"
 *   "accessible-child"
 *   "accessible-role"
 *   "accessible-state"
 *
 * accessibility property change listeners should use the
 *   normal GObject property interfaces and "properties_changed"
 *   signal handler semantics to interpret the property change
 *   information relayed from AtkObject.
 *   (AtkObject instances will connect to the "properties_changed"
 *   signal in their host objects, and relay the signals when appropriate).
 */

/* For other signals, see related interfaces
 *
 *    AtkActionIface,
 *    AtkComponentIface,
 *    AtkHypertextIface,
 *    AtkImageIface,
 *    AtkSelectionIface,
 *    AtkTableIface,
 *    AtkTextIface,
 *    AtkValueIface.
 *
 *  The usage model for obtaining these interface instances is:
 *    ATK_<interfacename>_GET_IFACE(GObject *accessible),
 *    where accessible, though specified as a GObject, is
 *    the AtkObject instance being queried.
 *  More usually, the interface will be used via a cast to the
 *    interface's corresponding "type":
 *
 *    AtkText textImpl = ATK_TEXT(accessible);
 *    if (textImpl)
 *      {
 *        cpos = atk_text_get_caret_position(textImpl);
 *      }
 *
 *  If it's known in advance that accessible implements AtkTextIface,
 *    this is shortened to:
 *
 *    cpos = atk_text_get_caret_position (ATK_TEXT (accessible));
 */

typedef enum
{
  ATK_RELATION_NULL = 0,

  ATK_RELATION_CONTROLLED_BY,
  ATK_RELATION_CONTROLLER_FOR,
  ATK_RELATION_LABEL_FOR,
  ATK_RELATION_LABELLED_BY,
  ATK_RELATION_MEMBER_OF,
  ATK_RELATION_LAST_DEFINED
} AtkRelationType;

AtkRelationType atk_relation_type_register            (gchar *name);

/*
 * Create a new relation for the specified key and the specified list
 * of targets.
 */
AtkRelation*    atk_relation_new                      (GArray          *target,
                                                       AtkRelationType relationship);
/*
 * Returns whether the relation set contains a relation that matches the
 * specified type.
 */
gboolean        atk_relation_set_contains             (AtkRelationSet  *set,
                                                       AtkRelationType relationship);
/*
 * Remove a relation from the from the relation set.
 */
void            atk_relation_set_remove               (AtkRelationSet  *set,
                                                       AtkRelation     *relation);
/*
 * Add a new relation to the current relation set if it is not already
 * present.
 */
void            atk_relation_set_add                  (AtkRelationSet  *set,
                                                       AtkRelation     *relation);
/*
 * Returns the number of relations in a relation set.
 */
gint            atk_relation_set_get_n_relations      (AtkRelationSet  *set);
/*
 * Returns the relation at the specified position in the relation set.
 */
AtkRelation*    atk_relation_set_get_relation         (AtkRelationSet  *set,
                                                       gint            i);
/*
 * Returns a relation that matches the specified type.
 */
AtkRelation*    atk_relation_set_get_relation_by_type (AtkRelationSet  *set,
                                                       AtkRelationType relationship);

/*
 * Returns the type of a relation.
 */
AtkRelationType atk_relation_get_type                 (AtkRelation     *relation);
/*
 * Returns the target list of a relation.
 */
GArray*         atk_relation_get_target               (AtkRelation     *relation);

gchar*          atk_state_mask_get_name                  (AtkStateMask    state);
AtkStateMask    atk_state_mask_for_name                  (gchar           *name);

#ifdef __cplusplus
}
#endif /* __cplusplus */


#endif /* __ATK_OBJECT_H__ */