| //////////////////////////////////////////////////////////////////////////////// |
| // |
| // Licensed to the Apache Software Foundation (ASF) under one or more |
| // contributor license agreements. See the NOTICE file distributed with |
| // this work for additional information regarding copyright ownership. |
| // The ASF licenses this file to You under the Apache License, Version 2.0 |
| // (the "License"); you may not use this file except in compliance with |
| // the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| // |
| //////////////////////////////////////////////////////////////////////////////// |
| |
| package spark.accessibility |
| { |
| |
| import flash.accessibility.Accessibility; |
| import flash.events.Event; |
| import flash.events.KeyboardEvent; |
| import flash.ui.Keyboard; |
| |
| import mx.accessibility.AccImpl; |
| import mx.accessibility.AccConst; |
| import mx.core.UIComponent; |
| import mx.core.mx_internal; |
| |
| import spark.components.supportClasses.ButtonBase; |
| import spark.components.supportClasses.ToggleButtonBase; |
| |
| use namespace mx_internal; |
| |
| /** |
| * ButtonBaseAccImpl is the accessibility implementation class |
| * for spark.components.supportClasses.ButtonBase. |
| * |
| * <p>Although ToggleButton, CheckBox, and RadioButton have their own |
| * accessibility implementation subclasses, |
| * Button simply uses the one for ButtonBase. |
| * Therefore, the rest of this description refers to |
| * the commonly-used Button component rather than the ButtonBase base class.</p> |
| * |
| * <p>When a Spark Button is created, |
| * its <code>accessibilityImplementation</code> 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 Button. |
| * See the mx.accessibility.AccImpl and |
| * flash.accessibility.AccessibilityImplementation classes |
| * for background information about accessibility implementation |
| * classes and MSAA.</p> |
| * |
| * <p><b>Children</b></p> |
| * |
| * <p>A Button has no MSAA children.</p> |
| * |
| * <p><b>Role</b></p> |
| * |
| * <p>The MSAA Role of a Button is ROLE_SYSTEM_PUSHBUTTON.</p> |
| * |
| * <p><b>Name</b></p> |
| * |
| * <p>The MSAA Name of a Button is, by default, the label that it displays. |
| * When wrapped in a FormItem element, |
| * this label will be combined with the FormItem's label. |
| * To override this behavior, |
| * set the Button's <code>accessibilityName</code> property.</p> |
| * |
| * <p>When the Name changes, |
| * a Button dispatches the MSAA event EVENT_OBJECT_NAMECHANGE.</p> |
| * |
| * <p><b>Description</b></p> |
| * |
| * <p>The MSAA Description of a Button is, by default, the empty string, |
| * but you can set the Button's <code>accessibilityDescription</code> |
| * property.</p> |
| * |
| * <p><b>State</b></p> |
| * |
| * <p>The MSAA State of a Button is a combination of: |
| * <ul> |
| * <li>STATE_SYSTEM_UNAVAILABLE (when enabled is false)</li> |
| * <li>STATE_SYSTEM_FOCUSABLE (when enabled is true)</li> |
| * <li>STATE_SYSTEM_FOCUSED (when enabled is true |
| * and the Button has focus)</li> |
| * </ul></p> |
| * |
| * <p>When the State changes, |
| * a Button dispatches the MSAA event EVENT_OBJECT_STATECHANGE.</p> |
| * |
| * <p><b>Value</b></p> |
| * |
| * <p>A Button does not have an MSAA Value.</p> |
| * |
| * <p><b>Location</b></p> |
| * |
| * <p>The MSAA Location of a Button is its bounding rectangle.</p> |
| * |
| * <p><b>Default Action</b></p> |
| * |
| * <p>The MSAA DefaultAction of a Button is "Press".</p> |
| * |
| * <p>When an MSAA client tells the Button to perform this action, |
| * KEY_DOWN and KEY_UP MouseEvents for the SPACE key are generated, |
| * to simulate pressing the ButtonBase via the keyboard, |
| * if the Button is enabled.</p> |
| * |
| * <p><b>Focus</b></p> |
| * |
| * <p>A Button accepts focus. |
| * When it does so, it dispatches the MSAA event EVENT_OBJECT_FOCUS.</p> |
| * |
| * <p><b>Selection</b></p> |
| * |
| * <p>A Button does not support selection in the MSAA sense.</p> |
| * |
| * @langversion 3.0 |
| * @playerversion Flash 10 |
| * @playerversion AIR 1.5 |
| * @productversion Flex 4 |
| */ |
| public class ButtonBaseAccImpl extends AccImpl |
| { |
| include "../core/Version.as"; |
| |
| //-------------------------------------------------------------------------- |
| // |
| // Class methods |
| // |
| //-------------------------------------------------------------------------- |
| |
| /** |
| * Enables accessibility in the Button class. |
| * |
| * <p>This method is called by application startup code |
| * that is autogenerated by the MXML compiler. |
| * Afterwards, when instances of Button are initialized, |
| * their <code>accessibilityImplementation</code> property |
| * will be set to an instance of this class.</p> |
| * |
| * @langversion 3.0 |
| * @playerversion Flash 10 |
| * @playerversion AIR 1.5 |
| * @productversion Flex 4 |
| */ |
| public static function enableAccessibility():void |
| { |
| ButtonBase.createAccessibilityImplementation = |
| createAccessibilityImplementation; |
| } |
| |
| /** |
| * @private |
| * Creates a Button's AccessibilityImplementation object. |
| * This method is called from UIComponent's |
| * initializeAccessibility() method. |
| */ |
| mx_internal static function createAccessibilityImplementation( |
| component:UIComponent):void |
| { |
| component.accessibilityImplementation = |
| new ButtonBaseAccImpl(component); |
| } |
| |
| //-------------------------------------------------------------------------- |
| // |
| // Constructor |
| // |
| //-------------------------------------------------------------------------- |
| |
| /** |
| * Constructor. |
| * |
| * @param master The UIComponent instance that this AccImpl instance |
| * is making accessible. |
| * |
| * @langversion 3.0 |
| * @playerversion Flash 10 |
| * @playerversion AIR 1.5 |
| * @productversion Flex 4 |
| */ |
| public function ButtonBaseAccImpl(master:UIComponent) |
| { |
| super(master); |
| |
| role = AccConst.ROLE_SYSTEM_PUSHBUTTON; |
| } |
| |
| //-------------------------------------------------------------------------- |
| // |
| // Overridden properties: AccImpl |
| // |
| //-------------------------------------------------------------------------- |
| |
| //---------------------------------- |
| // eventsToHandle |
| //---------------------------------- |
| |
| /** |
| * @private |
| * Array of events that we should listen for from the master component. |
| */ |
| override protected function get eventsToHandle():Array |
| { |
| return super.eventsToHandle.concat([ "click", "labelChanged" ]); |
| } |
| |
| //-------------------------------------------------------------------------- |
| // |
| // Overridden methods: AccessibilityImplementation |
| // |
| //-------------------------------------------------------------------------- |
| |
| /** |
| * @private |
| * IAccessible method for returning the state of the Button. |
| * States are predefined for all the components in MSAA. |
| * Values are assigned to each state. |
| * |
| * @param childID uint |
| * |
| * @return State uint |
| */ |
| override public function get_accState(childID:uint):uint |
| { |
| var accState:uint = getState(childID); |
| |
| return accState; |
| } |
| |
| /** |
| * @private |
| * IAccessible method for returning the default action |
| * of the Button, which is Press. |
| * |
| * @param childID uint |
| * |
| * @return DefaultAction String |
| */ |
| override public function get_accDefaultAction(childID:uint):String |
| { |
| return "Press"; |
| } |
| |
| /** |
| * @private |
| * IAccessible method for performing the default action |
| * associated with Button, which is Press. |
| * |
| * @param childID uint |
| */ |
| override public function accDoDefaultAction(childID:uint):void |
| { |
| if (master.enabled) |
| { |
| var event:KeyboardEvent = new KeyboardEvent(KeyboardEvent.KEY_DOWN); |
| event.keyCode = Keyboard.SPACE; |
| master.dispatchEvent(event); |
| |
| event = new KeyboardEvent(KeyboardEvent.KEY_UP); |
| event.keyCode = Keyboard.SPACE; |
| master.dispatchEvent(event); |
| } |
| } |
| |
| //-------------------------------------------------------------------------- |
| // |
| // Overridden methods: AccImpl |
| // |
| //-------------------------------------------------------------------------- |
| |
| /** |
| * @private |
| * method for returning the name of the Button |
| * which is spoken out by the screen reader |
| * The Button should return the label inside as the name of the Button. |
| * The name returned here would take precedence over the name |
| * specified in the accessibility panel. |
| * |
| * @param childID uint |
| * |
| * @return Name String |
| */ |
| override protected function getName(childID:uint):String |
| { |
| var label:String = ButtonBase(master).label; |
| |
| return label != null && label != "" ? label : ""; |
| } |
| |
| //-------------------------------------------------------------------------- |
| // |
| // Overridden event handlers: AccImpl |
| // |
| //-------------------------------------------------------------------------- |
| |
| /** |
| * @private |
| * Override the generic event handler. |
| * All AccImpl must implement this |
| * to listen for events from its master component. |
| */ |
| override protected function eventHandler(event:Event):void |
| { |
| // Let AccImpl class handle the events |
| // that all accessible UIComponents understand. |
| $eventHandler(event); |
| |
| switch (event.type) |
| { |
| case "click": |
| { |
| Accessibility.sendEvent(master, 0, AccConst.EVENT_OBJECT_STATECHANGE); |
| Accessibility.updateProperties(); |
| break; |
| } |
| |
| case "labelChanged": |
| { |
| Accessibility.sendEvent(master, 0, AccConst.EVENT_OBJECT_NAMECHANGE); |
| Accessibility.updateProperties(); |
| break; |
| } |
| } |
| } |
| } |
| |
| } |
