Adobe® Flex® 4 Language Reference
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spark.accessibility 
ComboBoxAccImpl 
Packagespark.accessibility
Classpublic class ComboBoxAccImpl
InheritanceComboBoxAccImpl Inheritance DropDownListBaseAccImpl 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

ComboBoxAccImpl is the accessibility implementation class for spark.components.ComboBox.

When a Spark ComboBox 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 ComboBox. 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 ComboBox are its editable TextInput (with childID 1) and its list items (with childIDs 2, 3, ... n). The number of children is one plus the number of items in the dataProvider (not one plus the the number of visible renderers).

As described below, the accessibility of the TextInput and the list items is managed by the ComboBox; their accessibilityImplementation and accessibilityProperties are ignored by the Flash Player.

Role

The MSAA Role of a ComboBox is ROLE_SYSTEM_COMBOBOX.

The MSAA Role of the editable TextInput is ROLE_SYSTEM_TEXT.

The Role of each list item is ROLE_SYSTEM_LISTITEM.

Name

The MSAA Name of a ComboBox (as well as its editable TextInput) 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 ComboBox's accessibilityName property.

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

When the Name of the ComboBox or one of its items changes, a ComboBox 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 ComboBox, by default, an empty string, but you can set the ComboBox's accessibilityDescription property.

The Description of each list item is the empty string.

State

The MSAA State of a ComboBox 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 ComboBox has focus)
  • STATE_SYSTEM_EXPANDED (when it is open)
  • STATE_SYSTEM_COLLAPSED (when it is closed)

The State of the editable TextInput 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 ComboBox has focus)

The State of a list item is a combination of:

  • STATE_SYSTEM_FOCUSABLE
  • STATE_SYSTEM_FOCUSED (when it has focus)
  • STATE_SYSTEM_SELECTABLE
  • STATE_SYSTEM_SELECTED (when it is selected)

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

Value

The MSAA Value of a ComboBox is the MSAA Name of the currently selected list item or the text entered into the TextInput.

The Value of a list item is always the empty string.

When the Value of the ComboBox changes, a ComboBox dispatches the MSAA event EVENT_OBJECT_VALUECHANGE.

Location

The MSAA Location of a ComboBox, its TextInput, or one of its list items is its bounding rectangle.

Default Action

Neither the ComboBox or it's TextInput have an MSAA DefaultAction.

The DefaultAction of a list item is "Double Click". Performing this action will select the item.

Focus

The ComboBox itself can receive focus, as well as its list items (either while the ComboBox is collapsed or expanded).

Selection

The ComboBox allows a single item to be selected, in which case an EVENT_OBJECT_SELECTION event is fired.



Public Properties
 PropertyDefined By
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
 Inheritederrno : uint
Errors are indicated out-of-band, rather than in return values.
AccessibilityImplementation
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
 Inheritedstub : Boolean
If a component is released without an ActionScript accessibility implementation, it is strongly suggested that a component accessibility stub be included.
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.
ComboBoxAccImpl
 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(selFlag:uint, childID:uint):void
IAccessible method for altering the selection in the component that this AccessibilityImplementation represents.
AccessibilityImplementation
  
[static] Enables accessibility in the ComboBox class.
ComboBoxAccImpl
 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
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

ComboBoxAccImpl

()Constructor
public function ComboBoxAccImpl(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 ComboBox class.

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