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phoenix_title wx.Accessible

The wx.Accessible class allows wxWidgets applications, and wxWidgets itself, to return extended information about user interface elements to client applications such as screen readers.

This is the main way in which wxWidgets implements accessibility features.

At present, only Microsoft Active Accessibility is supported by this class.

To use this class, derive from wx.Accessible, implement appropriate functions, and associate an object of the class with a window using wx.Window.SetAccessible .

All functions return an indication of success, failure, or not implemented using values of the AccStatus enum type.

If you return ACC_NOT_IMPLEMENTED from any function, the system will try to implement the appropriate functionality. However this will not work with all functions.

Most functions work with an object id, which can be zero to refer to ‘this’ UI element, or greater than zero to refer to the nth child element. This allows you to specify elements that don’t have a corresponding wx.Window or wx.Accessible; for example, the sash of a splitter window.

For details on the semantics of functions and types, please refer to the Microsoft Active Accessibility 1.2 documentation.

This class is compiled into wxWidgets only if the wx.USE_ACCESSIBILITY setup symbol is set to 1.

Availability

Only available for MSW.

See also

Accessibility Sample


class_hierarchy Class Hierarchy

Inheritance diagram for class Accessible:


method_summary Methods Summary

__init__ Constructor, taking an optional window.
DoDefaultAction Performs the default action for the object.
GetChild Gets the specified child (starting from 1).
GetChildCount Returns the number of children in childCount.
GetDefaultAction Gets the default action for this object (0) or a child (greater than 0).
GetDescription Returns the description for this object or a child.
GetFocus Gets the window with the keyboard focus.
GetHelpText Returns help text for this object or a child, similar to tooltip text.
GetKeyboardShortcut Returns the keyboard shortcut for this object or child.
GetLocation Returns the rectangle for this object (id is 0) or a child element (id is greater than 0).
GetName Gets the name of the specified object.
GetParent Returns the parent of this object, or None.
GetRole Returns a role constant describing this object.
GetSelections Gets a variant representing the selected children of this object.
GetState Returns a state constant.
GetValue Returns a localized string representing the value for the object or child.
GetWindow Returns the window associated with this object.
HitTest Returns a status value and object id to indicate whether the given point was on this or a child object.
Navigate Navigates from fromId to toId or to toObject.
NotifyEvent Allows the application to send an event when something changes in an accessible object.
Select Selects the object or child.
SetWindow Sets the window associated with this object.

property_summary Properties Summary

Window See GetWindow and SetWindow

api Class API


class wx.Accessible(Object)

Possible constructors:

Accessible(win=None)

The Accessible class allows wxWidgets applications, and wxWidgets itself, to return extended information about user interface elements to client applications such as screen readers.


Methods


__init__(self, win=None)

Constructor, taking an optional window.

The object can be associated with a window later.

Parameters:win (wx.Window) –

DoDefaultAction(self, childId)

Performs the default action for the object.

childId is 0 (the action for this object) or greater than 0 (the action for a child).

Parameters:childId (int) –
Return type: wx.AccStatus
Returns:wx.ACC_NOT_SUPPORTED if there is no default action for this window (e.g. an edit control).

GetChild(self, childId)

Gets the specified child (starting from 1).

If child is None and the return value is wx.ACC_OK, this means that the child is a simple element and not an accessible object.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, child )

GetChildCount(self)

Returns the number of children in childCount.

Return type:tuple
Returns:( wx.AccStatus, childCount )

GetDefaultAction(self, childId)

Gets the default action for this object (0) or a child (greater than 0).

Return wx.ACC_OK even if there is no action. actionName is the action, or the empty string if there is no action. The retrieved string describes the action that is performed on an object, not what the object does as a result. For example, a toolbar button that prints a document has a default action of “Press” rather than “Prints the current document.”

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, actionName )

GetDescription(self, childId)

Returns the description for this object or a child.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, description )

GetFocus(self, childId)

Gets the window with the keyboard focus.

If childId is 0 and child is None, no object in this subhierarchy has the focus. If this object has the focus, child should be ‘this’.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, child )

GetHelpText(self, childId)

Returns help text for this object or a child, similar to tooltip text.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, helpText )

GetKeyboardShortcut(self, childId)

Returns the keyboard shortcut for this object or child.

Returns e.g. ALT+K.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, shortcut )

GetLocation(self, elementId)

Returns the rectangle for this object (id is 0) or a child element (id is greater than 0).

rect is in screen coordinates.

Parameters:elementId (int) –
Return type:tuple
Returns:( wx.AccStatus, rect )

GetName(self, childId)

Gets the name of the specified object.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, name )

GetParent(self)

Returns the parent of this object, or None.

Return type:tuple
Returns:( wx.AccStatus, parent )

GetRole(self, childId)

Returns a role constant describing this object.

See AccRole for a list of these roles.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, role )

GetSelections(self)

Gets a variant representing the selected children of this object.

Acceptable values are:

  • a null variant (IsNull() returns True)
  • a list variant (GetType() == “list”)
  • an integer representing the selected child element, or 0 if this object is selected (GetType() == “long”)
  • a “voidx” pointer to a wx.Accessible child object
Return type:tuple
Returns:( wx.AccStatus, selections )

GetState(self, childId)

Returns a state constant.

See AccStatus for a list of these states.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, state )

GetValue(self, childId)

Returns a localized string representing the value for the object or child.

Parameters:childId (int) –
Return type:tuple
Returns:( wx.AccStatus, strValue )

GetWindow(self)

Returns the window associated with this object.

Return type: wx.Window

HitTest(self, pt, childId, childObject)

Returns a status value and object id to indicate whether the given point was on this or a child object.

Can return either a child object, or an integer representing the child element, starting from 1.

pt is in screen coordinates.

Parameters:
Return type:

wx.AccStatus

Navigate(self, navDir, fromId, toId, toObject)

Navigates from fromId to toId or to toObject.

Parameters:
Return type:

wx.AccStatus

static NotifyEvent(eventType, window, objectType, objectId)

Allows the application to send an event when something changes in an accessible object.

Parameters:
  • eventType (int) –
  • window (wx.Window) –
  • objectType (AccObject) –
  • objectId (int) –

Select(self, childId, selectFlags)

Selects the object or child.

See AccSelectionFlags for a list of the selection actions.

Parameters:
Return type:

wx.AccStatus

SetWindow(self, window)

Sets the window associated with this object.

Parameters:window (wx.Window) –

Properties


Window

See GetWindow and SetWindow