Adobe® Flex® 4 Language Reference
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spark.accessibility 
ListAccImpl 
Packagespark.accessibility
Classpublic class ListAccImpl
InheritanceListAccImpl Inheritance ListBaseAccImpl Inheritance AccImpl Inheritance AccessibilityImplementation Inheritance Object

Language Version: ActionScript 3.0
Product Version: Flex 4
Runtime Versions: Flash Player 10, AIR 1.5

ListAccImpl is the accessibility implementation class for spark.components.List.

When a Spark ListBase is created, its accessibilityImplementation property is set to an instance of this class. The Flash Player then uses this class to allow MSAA clients such as screen readers to see and manipulate the List. See the mx.accessibility.AccImpl and flash.accessibility.AccessibilityImplementation classes for background information about accessibility implementation classes and MSAA.

Children

The MSAA children of a list are its list items. The number of children is the number of items in the dataProvider, not just the number of visible renderers.

As described above, the accessibility of the list items is managed by the List; the accessibilityImplementation and accessibilityProperties of the item renderers are ignored by the Flash Player.

Role

The MSAA Role of a List is ROLE_SYSTEM_LIST.

The Role of each list item in the List is ROLE_SYSTEM_LISTITEM.

Name

The MSAA Name of a List is, by default, an empty string. When wrapped in a FormItem element, the Name is the FormItem's label. To override this behavior, set the List's accessibilityName property.

The Name of each list item is determined by the List's itemToLabel() method.

When the Name of the List or one of its items changes, a List dispatches the MSAA event EVENT_OBJECT_NAMECHANGE with the proper childID for a list item or 0 for itself.

Description

The MSAA Description of a List is, by default, an empty string, but you can set the List's accessibilityDescription property.

The Description of each list item is the empty string.

State

The MSAA State of a List is a combination of:

  • STATE_SYSTEM_UNAVAILABLE (when enabled is false)
  • STATE_SYSTEM_FOCUSABLE (when enabled is true)
  • STATE_SYSTEM_FOCUSED (when enabled is true and the List has focus)
  • STATE_SYSTEM_MULTISELECTABLE (when allowMultipleSelection is true)

The State of a list item is a combination of:

  • STATE_SYSTEM_FOCUSABLE
  • STATE_SYSTEM_FOCUSED (when focused)
  • STATE_SYSTEM_SELECTABLE
  • STATE_SYSTEM_SELECTED (when it has the caret)

When the State of the List or one of its items changes, a List dispatches the MSAA event EVENT_OBJECT_STATECHANGE with the proper childID for the list item or 0 for itself.

Value

A List or list item does not have an MSAA Value.

Location

The MSAA Location of a List or a list item is its bounding rectangle.

Default Action

A List does not have an MSAA DefaultAction.

The MSAA DefaultAction of a list item is "Double Click".

Performing the default action on a list item will cause it to be selected.

Focus

A List accepts focus. When it does so, it dispatches the MSAA event EVENT_OBJECT_FOCUS.

Selection

A List allows either a single or multiple list items to be selected, depending on the allowMultipleSelection property. When an item is selected, it dispatches MSAA event EVENT_OBJECT_SELECTION.



Public Properties
 PropertyDefined By
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
 Inheritederrno : uint
Indicates an error code.
AccessibilityImplementation
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
 Inheritedstub : Boolean
Used to create a component accessibility stub.
AccessibilityImplementation
Protected Properties
 PropertyDefined By
 InheritedeventsToHandle : Array
[read-only] All subclasses must override this function by returning an array of strings of the events to listen for.
AccImpl
 Inheritedmaster : UIComponent
A reference to the UIComponent instance that this AccImpl instance is making accessible.
AccImpl
 Inheritedrole : uint
Accessibility role of the component being made accessible.
AccImpl
Public Methods
 MethodDefined By
  
Constructor.
ListAccImpl
 Inherited
An IAccessible method that performs the default action associated with the component that this AccessibilityImplementation represents or of one of its child elements.
AccessibilityImplementation
 Inherited
accLocation(childID:uint):*
MSAA method for returning a DisplayObject or Rectangle specifying the bounding box of a child element in the AccessibilityImplementation.
AccessibilityImplementation
 Inherited
accSelect(operation:uint, childID:uint):void
IAccessible method for altering the selection in the component that this AccessibilityImplementation represents.
AccessibilityImplementation
  
[static] Enables accessibility in the List class.
ListAccImpl
 Inherited
MSAA method for returning the default action of the component that this AccessibilityImplementation represents or of one of its child elements.
AccessibilityImplementation
 Inherited
MSAA method for returning the unsigned integer ID of the child element, if any, that has child focus within the component.
AccessibilityImplementation
 Inherited
MSAA method for returning the name for the component that this AccessibilityImplementation represents or for one of its child elements.
AccessibilityImplementation
 Inherited
MSAA method for returning the system role for the component that this AccessibilityImplementation represents or for one of its child elements.
AccessibilityImplementation
 Inherited
MSAA method for returning an array containing the IDs of all child elements that are selected.
AccessibilityImplementation
 Inherited
IAccessible method for returning the current runtime state of the component that this AccessibilityImplementation represents or of one of its child elements.
AccessibilityImplementation
 Inherited
MSAA method for returning the runtime value of the component that this AccessibilityImplementation represents or of one of its child elements.
AccessibilityImplementation
 Inherited
Returns an array containing the unsigned integer IDs of all child elements in the AccessibilityImplementation.
AccessibilityImplementation
 Inherited
[static] Method for supporting Form Accessibility.
AccImpl
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
[static] Method for supporting state Accessibility.
AccImpl
 Inherited
Returns true or false to indicate whether a text object having a bounding box specified by a x, y, width, and height should be considered a label for the component that this AccessibilityImplementation represents.
AccessibilityImplementation
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
Protected Methods
 MethodDefined By
 Inherited
Generic event handler.
AccImpl
 Inherited
Returns the name of the accessible component.
AccImpl
 Inherited
getState(childID:uint):uint
Utility method to determine state of the accessible component.
AccImpl
Constructor Detail

ListAccImpl

()Constructor
public function ListAccImpl(master:UIComponent)

Language Version: ActionScript 3.0
Product Version: Flex 4
Runtime Versions: Flash Player 10, AIR 1.5

Constructor.

Parameters
master:UIComponent — The UIComponent instance that this AccImpl instance is making accessible.
Method Detail

enableAccessibility

()method
public static function enableAccessibility():void

Language Version: ActionScript 3.0
Product Version: Flex 4
Runtime Versions: Flash Player 10, AIR 1.5

Enables accessibility in the List class.

This method is called by application startup code that is autogenerated by the MXML compiler. Afterwards, when instances of List are initialized, their accessibilityImplementation property will be set to an instance of this class.