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#include "qaccessible.h"
#ifndef QT_NO_ACCESSIBILITY
#include "qaccessibleplugin.h"
#include "qaccessiblewidget.h"
#include "qapplication.h"
#include "qhash.h"
#include "qmetaobject.h"
#include "qmutex.h"
#include <private/qfactoryloader_p.h>
#include "qwidget.h"
QT_BEGIN_NAMESPACE
/*!
\class QAccessible
\brief The QAccessible class provides enums and static functions
relating to accessibility.
\ingroup accessibility
Accessible applications can be used by people who are not able to
use applications by conventional means.
The functions in this class are used for communication between
accessible applications (also called AT Servers) and
accessibility tools (AT Clients), such as screen readers and
braille displays. Clients and servers communicate in the following way:
\list
\o \e{AT Servers} notify the clients about events through calls to the
updateAccessibility() function.
\o \e{AT Clients} request information about the objects in the server.
The QAccessibleInterface class is the core interface, and encapsulates
this information in a pure virtual API. Implementations of the interface
are provided by Qt through the queryAccessibleInterface() API.
\endlist
The communication between servers and clients is initialized by
the setRootObject() function. Function pointers can be installed
to replace or extend the default behavior of the static functions
in QAccessible.
Qt supports Microsoft Active Accessibility (MSAA), Mac OS X
Accessibility, and the Unix/X11 AT-SPI standard. Other backends
can be supported using QAccessibleBridge.
In addition to QAccessible's static functions, Qt offers one
generic interface, QAccessibleInterface, that can be used to wrap
all widgets and objects (e.g., QPushButton). This single
interface provides all the metadata necessary for the assistive
technologies. Qt provides implementations of this interface for
its built-in widgets as plugins.
When you develop custom widgets, you can create custom subclasses
of QAccessibleInterface and distribute them as plugins (using
QAccessiblePlugin) or compile them into the application.
Likewise, Qt's predefined accessibility support can be built as
plugin (the default) or directly into the Qt library. The main
advantage of using plugins is that the accessibility classes are
only loaded into memory if they are actually used; they don't
slow down the common case where no assistive technology is being
used.
Qt also includes two convenience classes, QAccessibleObject and
QAccessibleWidget, that inherit from QAccessibleInterface and
provide the lowest common denominator of metadata (e.g., widget
geometry, window title, basic help text). You can use them as
base classes when wrapping your custom QObject or QWidget
subclasses.
\sa QAccessibleInterface
*/
/*!
\enum QAccessible::Action
This enum describes the possible types of action that can occur.
\value DefaultAction
\value Press
\value SetFocus
\value Increase
\value Decrease
\value Accept
\value Cancel
\value Select
\value ClearSelection
\value RemoveSelection
\value ExtendSelection
\value AddToSelection
\value FirstStandardAction
\value LastStandardAction
*/
/*!
\enum QAccessible::Method
This enum describes the possible types of methods that can be
invoked on an accessible object.
\value ListSupportedMethods
\value SetCursorPosition
\value GetCursorPosition
\omitvalue ForegroundColor
\omitvalue BackgroundColor
\sa QAccessibleInterface::invokeMethod()
*/
/*!
\fn QSet<Method> QAccessibleInterface::supportedMethods()
\since 4.3
Returns a QSet of \l{QAccessible::}{Method}s that are supported by this
accessible interface.
\sa QAccessible::Method invokeMethod()
*/
/*!
\enum QAccessible::StateFlag
This enum type defines bit flags that can be combined to indicate
the state of an accessible object. The values are:
\value Animated The object's appearance changes frequently.
\value Busy The object cannot accept input at the moment.
\value Checked The object's check box is checked.
\value Collapsed The object is collapsed, e.g. a closed listview item, or an iconified window.
\value DefaultButton The object represents the default button in a dialog.
\value Expanded The object is expandable, and currently the children are visible.
\value ExtSelectable The object supports extended selection.
\value Focusable The object can receive focus. Only objects in the active window can receive focus.
\value Focused The object has keyboard focus.
\value HasPopup The object opens a popup.
\value HotTracked The object's appearance is sensitive to the mouse cursor position.
\value Invisible The object is not visible to the user.
\value Linked The object is linked to another object, e.g. a hyperlink.
\value Marqueed The object displays scrolling contents, e.g. a log view.
\value Mixed The state of the object is not determined, e.g. a tri-state check box that is neither checked nor unchecked.
\value Modal The object blocks input from other objects.
\value Movable The object can be moved.
\value MultiSelectable The object supports multiple selected items.
\value Normal The normal state.
\value Offscreen The object is clipped by the visible area. Objects that are off screen are also invisible.
\value Pressed The object is pressed.
\value Protected The object is password protected, e.g. a line edit for entering a Password.
\value ReadOnly The object can usually be edited, but is explicitly set to read-only.
\value Selectable The object is selectable.
\value Selected The object is selected.
\value SelfVoicing The object describes itself through speech or sound.
\value Sizeable The object can be resized, e.g. top-level windows.
\value Traversed The object is linked and has been visited.
\value Unavailable The object is unavailable to the user, e.g. a disabled widget.
\omitvalue Moveable
\omitvalue HasInvokeExtension
Implementations of QAccessibleInterface::state() return a combination
of these flags.
*/
/*!
\enum QAccessible::Event
This enum type defines accessible event types.
\value AcceleratorChanged
\value Alert A system alert (e.g., a message from a QMessageBox)
\value ContextHelpEnd Context help (QWhatsThis) for an object is finished.
\value ContextHelpStart Context help (QWhatsThis) for an object is initiated.
\value DefaultActionChanged The default QAccessible::Action for the accessible object changed
\value DescriptionChanged The objects QAccessible::Description changed.
\value DialogEnd A dialog (QDialog) is been hidden
\value DialogStart A dialog (QDialog) has been set visible.
\value DragDropEnd A Drag & Drop operation is about to finished.
\value DragDropStart A Drag & Drop operation is about to be initiated.
\value Focus An object has gained keyboard focus.
\value ForegroundChanged A window has been activated (i.e., a new window has gained focus on the desktop)
\value HelpChanged The QAccessible::Help text property of an object has changed
\value LocationChanged An objects location on the screen changed
\value MenuCommand A menu item is triggered.
\value MenuEnd A menu has been closed (Qt uses PopupMenuEnd for all menus)
\value MenuStart A menu has been opened on the menubar (Qt uses PopupMenuStart for all menus)
\value NameChanged The QAccessible::Name property of an object has changed
\value ObjectCreated A new object is created.
\value ObjectDestroyed An object is deleted.
\value ObjectHide An object is hidden (i.e., with QWidget::hide()). Any children the object that is hidden has do not send this event.
It is not send when an object is hidden as it is being obcured by others.
\value ObjectReorder A layout or item view has added, removed, or moved an object (Qt does not use this event).
\value ObjectShow An object is displayed (i.e., with QWidget::show()).
\value ParentChanged An objects parent object changed.
\value PopupMenuEnd A popup menu has closed.
\value PopupMenuStart A popupmenu has opened.
\value ScrollingEnd A scrollbar scroll operation has ended (the mouse has released the slider handle)
\value ScrollingStart A scrollbar scroll operation is about to start (i.e., the mouse has pressed on the slider handle)
\value Selection The selection has changed in a menu or item view.
\value SelectionAdd An item has been added to the selection in an item view.
\value SelectionRemove An item has been removed from an item view selection.
\value SelectionWithin Several changes to a selection has occurred in an item view.
\value SoundPlayed A sound has been played by an object
\value StateChanged The QAccessible::State of an object has changed.
\value ValueChanged The QAccessible::Value of an object has changed.
*/
/*!
\enum QAccessible::Role
This enum defines the role of an accessible object. The roles are:
\value AlertMessage An object that is used to alert the user.
\value Animation An object that displays an animation.
\value Application The application's main window.
\value Assistant An object that provids interactive help.
\value Border An object that represents a border.
\value ButtonDropDown A button that drops down a list of items.
\value ButtonDropGrid A button that drops down a grid.
\value ButtonMenu A button that drops down a menu.
\value Canvas An object that displays graphics that the user can interact with.
\value Caret An object that represents the system caret (text cursor).
\value Cell A cell in a table.
\value Chart An object that displays a graphical representation of data.
\value CheckBox An object that represents an option that can be checked or unchecked. Some options provide a "mixed" state, e.g. neither checked nor unchecked.
\value Client The client area in a window.
\value Clock A clock displaying time.
\value Column A column of cells, usually within a table.
\value ColumnHeader A header for a column of data.
\value ComboBox A list of choices that the user can select from.
\value Cursor An object that represents the mouse cursor.
\value Dial An object that represents a dial or knob.
\value Dialog A dialog box.
\value Document A document window, usually in an MDI environment.
\value EditableText Editable text
\value Equation An object that represents a mathematical equation.
\value Graphic A graphic or picture, e.g. an icon.
\value Grip A grip that the user can drag to change the size of widgets.
\value Grouping An object that represents a logical grouping of other objects.
\value HelpBalloon An object that displays help in a separate, short lived window.
\value HotkeyField A hotkey field that allows the user to enter a key sequence.
\value Indicator An indicator that represents a current value or item.
\value LayeredPane An object that can contain layered children, e.g. in a stack.
\value Link A link to something else.
\value List A list of items, from which the user can select one or more items.
\value ListItem An item in a list of items.
\value MenuBar A menu bar from which menus are opened by the user.
\value MenuItem An item in a menu or menu bar.
\value NoRole The object has no role. This usually indicates an invalid object.
\value PageTab A page tab that the user can select to switch to a different page in a dialog.
\value PageTabList A list of page tabs.
\value Pane A generic container.
\value PopupMenu A menu which lists options that the user can select to perform an action.
\value ProgressBar The object displays the progress of an operation in progress.
\value PropertyPage A property page where the user can change options and settings.
\value PushButton A button.
\value RadioButton An object that represents an option that is mutually exclusive with other options.
\value Row A row of cells, usually within a table.
\value RowHeader A header for a row of data.
\value ScrollBar A scroll bar, which allows the user to scroll the visible area.
\value Separator A separator that divides space into logical areas.
\value Slider A slider that allows the user to select a value within a given range.
\value Sound An object that represents a sound.
\value SpinBox A spin box widget that allows the user to enter a value within a given range.
\value Splitter A splitter distributing available space between its child widgets.
\value StaticText Static text, such as labels for other widgets.
\value StatusBar A status bar.
\value Table A table representing data in a grid of rows and columns.
\value TitleBar The title bar caption of a window.
\value ToolBar A tool bar, which groups widgets that the user accesses frequently.
\value ToolTip A tool tip which provides information about other objects.
\value Tree A list of items in a tree structure.
\value TreeItem An item in a tree structure.
\value UserRole The first value to be used for user defined roles.
\value Whitespace Blank space between other objects.
\value Window A top level window.
*/
/*!
\enum QAccessible::RelationFlag
This enum type defines bit flags that can be combined to indicate
the relationship between two accessible objects.
\value Unrelated The objects are unrelated.
\value Self The objects are the same.
\value Ancestor The first object is a parent of the second object.
\value Child The first object is a direct child of the second object.
\value Descendent The first object is an indirect child of the second object.
\value Sibling The objects are siblings.
\value Up The first object is above the second object.
\value Down The first object is below the second object.
\value Left The first object is left of the second object.
\value Right The first object is right of the second object.
\value Covers The first object covers the second object.
\value Covered The first object is covered by the second object.
\value FocusChild The first object is the second object's focus child.
\value Label The first object is the label of the second object.
\value Labelled The first object is labelled by the second object.
\value Controller The first object controls the second object.
\value Controlled The first object is controlled by the second object.
\omitvalue HierarchyMask
\omitvalue GeometryMask
\omitvalue LogicalMask
Implementations of relationTo() return a combination of these flags.
Some values are mutually exclusive.
Implementations of navigate() can accept only one distinct value.
*/
/*!
\enum QAccessible::Text
This enum specifies string information that an accessible object
returns.
\value Name The name of the object. This can be used both
as an identifier or a short description by
accessible clients.
\value Description A short text describing the object.
\value Value The value of the object.
\value Help A longer text giving information about how to use the object.
\value Accelerator The keyboard shortcut that executes the object's default action.
\value UserText The first value to be used for user defined text.
*/
/*!
\fn QAccessibleInterface::~QAccessibleInterface()
Destroys the object.
*/
/*!
\fn void QAccessible::initialize()
\internal
*/
/*!
\fn void QAccessible::cleanup()
\internal
*/
#if !defined(QT_NO_LIBRARY) && (!defined(QT_NO_SETTINGS) || !defined(Q_OS_WIN))
Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
(QAccessibleFactoryInterface_iid, QLatin1String("/accessible")))
#endif
Q_GLOBAL_STATIC(QList<QAccessible::InterfaceFactory>, qAccessibleFactories)
QAccessible::UpdateHandler QAccessible::updateHandler = 0;
QAccessible::RootObjectHandler QAccessible::rootObjectHandler = 0;
static bool accessibility_active = false;
static bool cleanupAdded = false;
static void qAccessibleCleanup()
{
qAccessibleFactories()->clear();
}
/*!
\typedef QAccessible::InterfaceFactory
A function pointer type. Use a function with this prototype to install
interface factories with installFactory().
The function receives a QObject pointer. If the QObject
provides a QAccessibleInterface, it sets the second parameter to
point to the corresponding QAccessibleInterface, and returns true;
otherwise returns false.
Installed factories are called by queryAccessibilityInterface() until
one provides an interface.
*/
/*!
\typedef QAccessible::UpdateHandler
\internal
A function pointer type. Use a function with this prototype to install
your own update function.
The function is called by updateAccessibility().
*/
/*!
\typedef QAccessible::RootObjectHandler
\internal
A function pointer type. Use a function with this prototype to install
your own root object handler.
The function is called by setRootObject().
*/
/*!
Installs the InterfaceFactory \a factory. The last factory added
is the first one used by queryAccessibleInterface().
*/
void QAccessible::installFactory(InterfaceFactory factory)
{
if (!factory)
return;
if (!cleanupAdded) {
qAddPostRoutine(qAccessibleCleanup);
cleanupAdded = true;
}
if (qAccessibleFactories()->contains(factory))
return;
qAccessibleFactories()->append(factory);
}
/*!
Removes \a factory from the list of installed InterfaceFactories.
*/
void QAccessible::removeFactory(InterfaceFactory factory)
{
qAccessibleFactories()->removeAll(factory);
}
/*!
\internal
Installs the given \a handler as the function to be used by
updateAccessibility(), and returns the previously installed
handler.
*/
QAccessible::UpdateHandler QAccessible::installUpdateHandler(UpdateHandler handler)
{
UpdateHandler old = updateHandler;
updateHandler = handler;
return old;
}
/*!
Installs the given \a handler as the function to be used by setRootObject(),
and returns the previously installed handler.
*/
QAccessible::RootObjectHandler QAccessible::installRootObjectHandler(RootObjectHandler handler)
{
RootObjectHandler old = rootObjectHandler;
rootObjectHandler = handler;
return old;
}
/*!
If a QAccessibleInterface implementation exists for the given \a object,
this function returns a pointer to the implementation; otherwise it
returns 0.
The function calls all installed factory functions (from most
recently installed to least recently installed) until one is found
that provides an interface for the class of \a object. If no
factory can provide an accessibility implementation for the class
the function loads installed accessibility plugins, and tests if
any of the plugins can provide the implementation.
If no implementation for the object's class is available, the
function tries to find an implementation for the object's parent
class, using the above strategy.
\warning The caller is responsible for deleting the returned
interface after use.
*/
QAccessibleInterface *QAccessible::queryAccessibleInterface(QObject *object)
{
accessibility_active = true;
QAccessibleInterface *iface = 0;
if (!object)
return 0;
QEvent e(QEvent::AccessibilityPrepare);
QApplication::sendEvent(object, &e);
const QMetaObject *mo = object->metaObject();
while (mo) {
const QLatin1String cn(mo->className());
for (int i = qAccessibleFactories()->count(); i > 0; --i) {
InterfaceFactory factory = qAccessibleFactories()->at(i - 1);
iface = factory(cn, object);
if (iface)
return iface;
}
#if !defined(QT_NO_LIBRARY) && (!defined(QT_NO_SETTINGS) || !defined(Q_OS_WIN))
QAccessibleFactoryInterface *factory = qobject_cast<QAccessibleFactoryInterface*>(loader()->instance(cn));
if (factory) {
iface = factory->create(cn, object);
if (iface)
return iface;
}
#endif
mo = mo->superClass();
}
QWidget *widget = qobject_cast<QWidget*>(object);
if (widget)
return new QAccessibleWidget(widget);
else if (object == qApp)
return new QAccessibleApplication();
return 0;
}
/*!
Returns true if an accessibility implementation has been requested
during the runtime of the application; otherwise returns false.
Use this function to prevent potentially expensive notifications via
updateAccessibility().
*/
bool QAccessible::isActive()
{
return accessibility_active;
}
/*!
\fn void QAccessible::setRootObject(QObject *object)
Sets the root accessible object of this application to \a object.
All other accessible objects in the application can be reached by the
client using object navigation.
You should never need to call this function. Qt sets the QApplication
object as the root object immediately before the event loop is entered
in QApplication::exec().
Use QAccessible::installRootObjectHandler() to redirect the function
call to a customized handler function.
\sa queryAccessibleInterface()
*/
/*!
\fn void QAccessible::updateAccessibility(QObject *object, int child, Event reason)
Notifies accessibility clients about a change in \a object's
accessibility information.
\a reason specifies the cause of the change, for example,
\c ValueChange when the position of a slider has been changed. \a
child is the (1-based) index of the child element that has changed.
When \a child is 0, the object itself has changed.
Call this function whenever the state of your accessible object or
one of its sub-elements has been changed either programmatically
(e.g. by calling QLabel::setText()) or by user interaction.
If there are no accessibility tools listening to this event, the
performance penalty for calling this function is small, but if determining
the parameters of the call is expensive you can test isActive() to
avoid unnecessary computations.
*/
/*!
\class QAccessibleInterface
\brief The QAccessibleInterface class defines an interface that exposes information
about accessible objects.
\ingroup accessibility
Accessibility tools (also called AT Clients), such as screen readers
or braille displays, require high-level information about
accessible objects in an application. Accessible objects provide
specialized input and output methods, making it possible for users
to use accessibility tools with enabled applications (AT Servers).
Every element that the user needs to interact with or react to is
an accessible object, and should provide this information. These
are mainly visual objects, such as widgets and widget elements, but
can also be content, such as sounds.
The AT client uses three basic concepts to acquire information
about any accessible object in an application:
\list
\i \e Properties The client can read information about
accessible objects. In some cases the client can also modify these
properties; such as text in a line edit.
\i \e Actions The client can invoke actions like pressing a button
or .
\i \e{Relationships and Navigation} The client can traverse from one
accessible object to another, using the relationships between objects.
\endlist
The QAccessibleInterface defines the API for these three concepts.
\section1 Relationships and Navigation
The functions childCount() and indexOfChild() return the number of
children of an accessible object and the index a child object has
in its parent. The childAt() function returns the index of a child
at a given position.
The relationTo() function provides information about how two
different objects relate to each other, and navigate() allows
traversing from one object to another object with a given
relationship.
\section1 Properties
The central property of an accessible objects is what role() it
has. Different objects can have the same role, e.g. both the "Add
line" element in a scroll bar and the \c OK button in a dialog have
the same role, "button". The role implies what kind of
interaction the user can perform with the user interface element.
An object's state() property is a combination of different state
flags and can describe both how the object's state differs from a
"normal" state, e.g. it might be unavailable, and also how it
behaves, e.g. it might be selectable.
The text() property provides textual information about the object.
An object usually has a name, but can provide extended information
such as a description, help text, or information about any
keyboard accelerators it provides. Some objects allow changing the
text() property through the setText() function, but this
information is in most cases read-only.
The rect() property provides information about the geometry of an
accessible object. This information is usually only available for
visual objects.
\section1 Actions and Selection
To enable the user to interact with an accessible object the
object must expose information about the actions that it can
perform. userActionCount() returns the number of actions supported by
an accessible object, and actionText() returns textual information
about those actions. doAction() invokes an action.
Objects that support selections can define actions to change the selection.
\section2 Objects and children
A QAccessibleInterface provides information about the accessible
object, and can also provide information for the children of that
object if those children don't provide a QAccessibleInterface
implementation themselves. This is practical if the object has
many similar children (e.g. items in a list view), or if the
children are an integral part of the object itself, for example, the
different sections in a scroll bar.
If an accessible object provides information about its children
through one QAccessibleInterface, the children are referenced
using indexes. The index is 1-based for the children, i.e. 0
refers to the object itself, 1 to the first child, 2 to the second
child, and so on.
All functions in QAccessibleInterface that take a child index
relate to the object itself if the index is 0, or to the child
specified. If a child provides its own interface implementation
(which can be retrieved through navigation) asking the parent for
information about that child will usually not succeed.
\sa QAccessible
*/
/*!
\fn bool QAccessibleInterface::isValid() const
Returns true if all the data necessary to use this interface
implementation is valid (e.g. all pointers are non-null);
otherwise returns false.
\sa object()
*/
/*!
\fn QObject *QAccessibleInterface::object() const
Returns a pointer to the QObject this interface implementation provides
information for.
\sa isValid()
*/
/*!
\fn int QAccessibleInterface::childCount() const
Returns the number of children that belong to this object. A child
can provide accessibility information on its own (e.g. a child
widget), or be a sub-element of this accessible object.
All objects provide this information.
\sa indexOfChild()
*/
/*!
\fn int QAccessibleInterface::indexOfChild(const QAccessibleInterface *child) const
Returns the 1-based index of the object \a child in this object's
children list, or -1 if \a child is not a child of this object. 0
is not a possible return value.
All objects provide this information about their children.
\sa childCount()
*/
/*!
\fn QAccessible::Relation QAccessibleInterface::relationTo(int child,
const QAccessibleInterface *other, int otherChild) const
Returns the relationship between this object's \a child and the \a
other object's \a otherChild. If \a child is 0 the object's own relation
is returned.
The returned value indicates the relation of the called object to
the \a other object, e.g. if this object is a child of \a other
the return value will be \c Child.
The return value is a combination of the bit flags in the
QAccessible::Relation enumeration.
All objects provide this information.
\sa indexOfChild(), navigate()
*/
/*!
\fn int QAccessibleInterface::childAt(int x, int y) const
Returns the 1-based index of the child that contains the screen
coordinates (\a x, \a y). This function returns 0 if the point is
positioned on the object itself. If the tested point is outside
the boundaries of the object this function returns -1.
This function is only relyable for visible objects (invisible
object might not be laid out correctly).
All visual objects provide this information.
\sa rect()
*/
/*!
\fn int QAccessibleInterface::navigate(RelationFlag relation, int entry, QAccessibleInterface
**target) const
Navigates from this object to an object that has a relationship
\a relation to this object, and returns the respective object in
\a target. It is the caller's responsibility to delete *\a target
after use.
If an object is found, \a target is set to point to the object, and
the index of the child of \a target is returned. The return value
is 0 if \a target itself is the requested object. \a target is set
to null if this object is the target object (i.e. the requested
object is a handled by this object).
If no object is found \a target is set to null, and the return
value is -1.
The \a entry parameter has two different meanings:
\list
\i \e{Hierarchical and Logical relationships} -- if multiple objects with
the requested relationship exist \a entry specifies which one to
return. \a entry is 1-based, e.g. use 1 to get the first (and
possibly only) object with the requested relationship.
The following code demonstrates how to use this function to
navigate to the first child of an object:
\snippet doc/src/snippets/code/src_gui_accessible_qaccessible.cpp 0
\i \e{Geometric relationships} -- the index of the child from
which to start navigating in the specified direction. \a entry
can be 0 to navigate to a sibling of this object, or non-null to
navigate within contained children that don't provide their own
accessible information.
\endlist
Note that the \c Descendent value for \a relation is not supported.
All objects support navigation.
\sa relationTo(), childCount()
*/
/*!
\fn QString QAccessibleInterface::text(Text t, int child) const
Returns the value of the text property \a t of the object, or of
the object's child if \a child is not 0.
The \l Name is a string used by clients to identify, find, or
announce an accessible object for the user. All objects must have
a name that is unique within their container. The name can be
used differently by clients, so the name should both give a
short description of the object and be unique.
An accessible object's \l Description provides textual information
about an object's visual appearance. The description is primarily
used to provide greater context for vision-impaired users, but is
also used for context searching or other applications. Not all
objects have a description. An "OK" button would not need a
description, but a tool button that shows a picture of a smiley
would.
The \l Value of an accessible object represents visual information
contained by the object, e.g. the text in a line edit. Usually,
the value can be modified by the user. Not all objects have a
value, e.g. static text labels don't, and some objects have a
state that already is the value, e.g. toggle buttons.
The \l Help text provides information about the function and
usage of an accessible object. Not all objects provide this
information.
The \l Accelerator is a keyboard shortcut that activates the
object's default action. A keyboard shortcut is the underlined
character in the text of a menu, menu item or widget, and is
either the character itself, or a combination of this character
and a modifier key like Alt, Ctrl or Shift. Command controls like
tool buttons also have shortcut keys and usually display them in
their tooltip.
All objects provide a string for \l Name.
\sa role(), state()
*/
/*!
\fn void QAccessibleInterface::setText(Text t, int child, const QString &text)
Sets the text property \a t of the object, or of the object's
child if \a child is not 0, to \a text.
Note that the text properties of most objects are read-only.
\sa text()
*/
/*!
\fn QRect QAccessibleInterface::rect(int child) const
Returns the geometry of the object, or of the object's child if \a child
is not 0. The geometry is in screen coordinates.
This function is only reliable for visible objects (invisible
objects might not be laid out correctly).
All visual objects provide this information.
\sa childAt()
*/
/*!
\fn QAccessible::Role QAccessibleInterface::role(int child) const
Returns the role of the object, or of the object's child if \a child
is not 0. The role of an object is usually static.
All accessible objects have a role.
\sa text(), state()
*/
/*!
\fn QAccessible::State QAccessibleInterface::state(int child) const
Returns the current state of the object, or of the object's child if
\a child is not 0. The returned value is a combination of the flags in
the QAccessible::StateFlag enumeration.
All accessible objects have a state.
\sa text(), role()
*/
/*!
\fn int QAccessibleInterface::userActionCount(int child) const
Returns the number of custom actions of the object, or of the
object's child if \a child is not 0.
The \c Action type enumerates predefined actions: these
are not included in the returned value.
\sa actionText(), doAction()
*/
/*!
\fn QString QAccessibleInterface::actionText(int action, Text t, int child) const
Returns the text property \a t of the action \a action supported by
the object, or of the object's child if \a child is not 0.
\sa text(), userActionCount()
*/
/*!
\fn bool QAccessibleInterface::doAction(int action, int child, const QVariantList ¶ms)
Asks the object, or the object's \a child if \a child is not 0, to
execute \a action using the parameters, \a params. Returns true if
the action could be executed; otherwise returns false.
\a action can be a predefined or a custom action.
\sa userActionCount(), actionText()
*/
/*!
\fn QColor QAccessibleInterface::backgroundColor()
\internal
*/
/*!
\fn QAccessibleEditableTextInterface *QAccessibleInterface::editableTextInterface()
\internal
*/
/*!
\fn QColor QAccessibleInterface::foregroundColor()
\internal
*/
/*!
\fn QAccessibleTextInterface *QAccessibleInterface::textInterface()
\internal
*/
/*!
\fn QAccessibleValueInterface *QAccessibleInterface::valueInterface()
\internal
*/
/*!
\fn QAccessibleTableInterface *QAccessibleInterface::tableInterface()
\internal
*/
/*!
\class QAccessibleEvent
\brief The QAccessibleEvent class is used to query addition
accessibility information about complex widgets.
The event can be of type QEvent::AccessibilityDescription or
QEvent::AccessibilityHelp.
Some QAccessibleInterface implementations send QAccessibleEvents
to the widget they wrap to obtain the description or help text of
a widget or of its children. The widget can answer by calling
setValue() with the requested information.
The default QWidget::event() implementation simply sets the text
to be the widget's \l{QWidget::toolTip}{tooltip} (for \l
AccessibilityDescription event) or its
\l{QWidget::whatsThis}{"What's This?" text} (for \l
AccessibilityHelp event).
\ingroup accessibility
\ingroup events
*/
/*!
\fn QAccessibleEvent::QAccessibleEvent(Type type, int child)
Constructs an accessibility event of the given \a type, which
must be QEvent::AccessibilityDescription or
QEvent::AccessibilityHelp.
\a child is the (1-based) index of the child to which the request
applies. If \a child is 0, the request is for the widget itself.
\sa child()
*/
/*!
\fn int QAccessibleEvent::child() const
Returns the (1-based) index of the child to which the request
applies. If the child is 0, the request is for the widget itself.
*/
/*!
\fn QString QAccessibleEvent::value() const
Returns the text set using setValue().
\sa setValue()
*/
/*!
\fn void QAccessibleEvent::setValue(const QString &text)
Set the description or help text for the given child() to \a
text, thereby answering the request.
\sa value()
*/
/*!
\since 4.2
Invokes a \a method on \a child with the given parameters \a params
and returns the result of the operation as QVariant.
Note that the type of the returned QVariant depends on the action.
Returns an invalid QVariant if the object doesn't support the action.
*/
QVariant QAccessibleInterface::invokeMethod(Method method, int child, const QVariantList ¶ms)
{
if (!(state(0) & HasInvokeExtension))
return QVariant();
return static_cast<QAccessibleInterfaceEx *>(this)->invokeMethodEx(method, child, params);
}
QVariant QAccessibleInterfaceEx::virtual_hook(const QVariant &)
{
return QVariant();
}
/*! \internal */
QAccessible2Interface *QAccessibleInterface::cast_helper(QAccessible2::InterfaceType t)
{
if (state(0) & HasInvokeExtension)
return static_cast<QAccessibleInterfaceEx *>(this)->interface_cast(t);
return 0;
}
QT_END_NAMESPACE
#endif