Package | flash.accessibility |
Class | public final class Accessibility |
Inheritance | Accessibility Object |
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0, Flash Player 9 |
Mobile Browser Support: This class is not supported in mobile browsers.
AIR profile support: This feature is supported on all desktop operating systems, but is not supported on mobile devices or on AIR for TV devices. See AIR Profile Support for more information regarding API support across multiple profiles.
To get and set accessible properties for a specific object, such as a button, movie
clip, or text field, use the DisplayObject.accessibilityProperties
property.
To determine whether the player or runtime is running in an environment that supports accessibility aids, use
the Capabilities.hasAccessibility
property.
Note: AIR 2 supports the JAWS 11 (or higher) screen reader software. For additional information, please see http://www.adobe.com/accessibility/.
Learn more
Related API Elements
Property | Defined By | ||
---|---|---|---|
active : Boolean [static] [read-only]
Indicates whether a screen reader is active and the application is
communicating with it. | Accessibility | ||
constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | ||
prototype : Object [static]
A reference to the prototype object of a class or function object. | Object |
Method | Defined By | ||
---|---|---|---|
Indicates whether an object has a specified property defined. | Object | ||
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | ||
Indicates whether the specified property exists and is enumerable. | Object | ||
Sets the availability of a dynamic property for loop operations. | Object | ||
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | ||
Returns the string representation of the specified object. | Object | ||
[static]
Tells Flash Player to apply any accessibility changes made by using the DisplayObject.accessibilityProperties property. | Accessibility | ||
Returns the primitive value of the specified object. | Object |
active | property |
active:Boolean
[read-only] Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0, Flash Player 9 |
Indicates whether a screen reader is active and the application is communicating with it. Use this method when you want your application to behave differently in the presence of a screen reader.
Once this property is set to true
, it remains true
for the duration
of the application. (It is unusual for a user to turn off the screen reader once it is
started.)
Note: Before calling this method, wait 1 or 2 seconds after launching your
AIR application or after the first appearance of the Flash® Player window in which
your document is playing. Otherwise, you might get a return value of false
even if there is an active accessibility client. This happens because of an asynchronous
communication mechanism between accessibility clients and Flash Player or AIR.
Capabilities.hasAccessibility
property.
Implementation
public static function get active():Boolean
Related API Elements
updateProperties | () | method |
public static function updateProperties():void
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0, Flash Player 9 |
Tells Flash Player to apply any accessibility changes made by using the DisplayObject.accessibilityProperties
property.
You need to call this method for your changes to take effect.
If you modify the accessibility properties for multiple objects, only one call to the
Accessibility.updateProperties()
method is necessary; multiple calls can result in
reduced performance and erroneous screen reader output.
Throws
IllegalOperationError — Accessibility is not supported in this version of
Flash Player. Do not call the Accessibility.updateProperties() method
if the flash.system.Capabilities.hasAccessibility property is false .
|
Related API Elements
AccessibilityExample
,
CustomAccessibleButton
, CustomSimpleButton
, and
ButtonDisplayState
sample classes to create an accessibility-compliant
menu that works with most screen readers. The example carries out the following tasks:
- It traces the
Accessibility.active
property to determine whether a screen reader is currently active and the player is communicating with it. - If the
active
property returnstrue
, the example calls theupdateProperties()
method to apply the accessibility changes made to the buttons in this example. - The example calls the
flash.utils.setTimeout()
method, specifying that theupdateAccessibility()
closure method should be called after 2 seconds.
Note: Call setTimeout()
before checking Accessibility.active
to give Flash Player the 2 seconds it needs to connect to a screen reader if one is available.
If you do not supply a sufficient delay time, the setTimeout
call might return false
even if a screen reader is available.
The following example processes the Accessibility.updateProperties()
method only if the call to Accessibility.active
returns true
, which occurs
only if Flash Player is currently connected to an active screen reader. If updateProperties
is called without an active screen reader, it throws an IllegalOperationError
exception.
package { import flash.display.Sprite; import flash.accessibility.Accessibility; import flash.utils.setTimeout; public class AccessibilityExample extends Sprite { public static const BUTTON_WIDTH:uint = 90; public static const BUTTON_HEIGHT:uint = 20; private var gutter:uint = 5; private var menuLabels:Array = new Array("PROJECTS", "PORTFOLIO", "CONTACT"); private var menuDescriptions:Array = new Array("Learn more about our projects" , "See our portfolio" , "Get in touch with our team"); public function AccessibilityExample() { configureAssets(); setTimeout(updateAccessibility, 2000); } private function updateAccessibility():void { trace("Accessibility.active: " + Accessibility.active); if(Accessibility.active) { Accessibility.updateProperties(); } } private function configureAssets():void { var child:CustomAccessibleButton; for(var i:uint; i < menuLabels.length; i++) { child = new CustomAccessibleButton(); child.y = (numChildren * (BUTTON_HEIGHT + gutter)); child.setLabel(menuLabels[i]); child.setDescription(menuDescriptions[i]); addChild(child); } } } } import flash.accessibility.AccessibilityProperties; import flash.display.Shape; import flash.display.SimpleButton; import flash.display.Sprite; import flash.events.Event; import flash.text.TextFormat; import flash.text.TextField; class CustomAccessibleButton extends Sprite { private var button:SimpleButton; private var label:TextField; private var description:String; private var _name:String; public function CustomAccessibleButton(_width:uint = 0, _height:uint = 0) { _width = (_width == 0) ? AccessibilityExample.BUTTON_WIDTH : _width; _height = (_height == 0) ? AccessibilityExample.BUTTON_HEIGHT : _height; button = buildButton(_width, _height); label = buildLabel(_width, _height); addEventListener(Event.ADDED, addedHandler); } private function addedHandler(event:Event):void { trace("addedHandler: " + this._name); var accessProps:AccessibilityProperties = new AccessibilityProperties(); accessProps.name = this._name; accessProps.description = description; accessibilityProperties = accessProps; removeEventListener(Event.ADDED, addedHandler); } private function buildButton(_width:uint, _height:uint):SimpleButton { var child:SimpleButton = new CustomSimpleButton(_width, _height); addChild(child); return child; } private function buildLabel(_width:uint, _height:uint):TextField { var format:TextFormat = new TextFormat(); format.font = "Verdana"; format.size = 11; format.color = 0xFFFFFF; format.align = TextFormatAlign.CENTER; format.bold = true; var child:TextField = new TextField(); child.y = 1; child.width = _width; child.height = _height; child.selectable = false; child.defaultTextFormat = format; child.mouseEnabled = false; addChild(child); return child; } public function setLabel(text:String):void { label.text = text; this._name = text; } public function setDescription(text:String):void { description = text; } } class CustomSimpleButton extends SimpleButton { private var upColor:uint = 0xFFCC00; private var overColor:uint = 0xCCFF00; private var downColor:uint = 0x00CCFF; public function CustomSimpleButton(_width:uint, _height:uint) { downState = new ButtonDisplayState(downColor, _width, _height); overState = new ButtonDisplayState(overColor, _width, _height); upState = new ButtonDisplayState(upColor, _width, _height); hitTestState = new ButtonDisplayState(upColor, _width, _height); useHandCursor = true; } } class ButtonDisplayState extends Shape { private var bgColor:uint; private var _width:uint; private var _height:uint; public function ButtonDisplayState(bgColor:uint, _width:uint, _height:uint) { this.bgColor = bgColor; this._width = _width; this._height = _height; draw(); } private function draw():void { graphics.beginFill(bgColor); graphics.drawRect(0, 0, _width, _height); graphics.endFill(); } }
Mon Nov 28 2011, 06:48 AM -08:00