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//
//  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 mx.accessibility
{

import flash.accessibility.Accessibility;
import flash.accessibility.AccessibilityProperties;
import flash.events.Event;

import mx.accessibility.AccConst;
import mx.controls.Alert;
import mx.core.UIComponent;
import mx.core.mx_internal;
import mx.managers.ISystemManager;

use namespace mx_internal;

/**
 *  AlertAccImpl is a subclass of AccessibilityImplementation
 *  which implements accessibility for the Alert class.
 *  
 *  @langversion 3.0
 *  @playerversion Flash 9
 *  @playerversion AIR 1.1
 *  @productversion Flex 3
 */
public class AlertAccImpl extends TitleWindowAccImpl
{
    include "../core/Version.as";

	//--------------------------------------------------------------------------
	//
	//  Class methods
	//
	//--------------------------------------------------------------------------

	/**
	 *  Enables accessibility in the Alert class.
	 * 
	 *  <p>This method is called by application startup code
	 *  that is autogenerated by the MXML compiler.
	 *  Afterwards, when instances of Alert are initialized,
	 *  their <code>accessibilityImplementation</code> property
	 *  will be set to an instance of this class.</p>
	 *  
	 *  @langversion 3.0
	 *  @playerversion Flash 9
	 *  @playerversion AIR 1.1
	 *  @productversion Flex 3
	 */
	public static function enableAccessibility():void
	{
		Alert.createAccessibilityImplementation =
			createAccessibilityImplementation;
	}

	/**
	 *  @private
	 *  Creates an Alert's AccessibilityImplementation object.
	 *  This method is called from UIComponent's
	 *  initializeAccessibility() method.
	 */
	mx_internal static function createAccessibilityImplementation(
								component:UIComponent):void
	{
		var titleBar:UIComponent = Alert(component).getTitleBar();
		var titleBarAccImpl:AlertAccImpl = new AlertAccImpl(component);
		titleBar.accessibilityImplementation = titleBarAccImpl;
	}

	//--------------------------------------------------------------------------
	//
	//  Constructor
	//
	//--------------------------------------------------------------------------

	/**
	 *  Constructor.
	 *
	 *  @param master The UIComponent instance that this AccImpl instance
	 *  is making accessible.
	 *  
	 *  @langversion 3.0
	 *  @playerversion Flash 9
	 *  @playerversion AIR 1.1
	 *  @productversion Flex 3
	 */
	public function AlertAccImpl(master:UIComponent)
	{
		super(master);
		
		role = AccConst.ROLE_SYSTEM_ALERT;
	}

	//--------------------------------------------------------------------------
	//
	//  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([ "close", "creationComplete" ]);
	}
	
	//--------------------------------------------------------------------------
	//
	//  Overridden methods: AccImpl
	//
	//--------------------------------------------------------------------------

	/**
	 *  @private
	 *  method for returning the name of the child
	 *  which is spoken out by the screen reader.
	 *
	 *  @param childID uint
	 *
	 *  @return Name String
	 */
	override protected function getName(childID:uint):String
	{
		return Alert(master).title + ", " + Alert(master).text;
	}

	//--------------------------------------------------------------------------
	//
	//  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);
				
		const systemManager:ISystemManager = ISystemManager(master.parent);
		var titleBar:UIComponent;
		
		switch (event.type)
		{
			case "close":
			{
				titleBar = Alert(master).getTitleBar();

				Accessibility.sendEvent(titleBar,0,AccConst.EVENT_SYSTEM_DIALOGEND);
				Accessibility.sendEvent(titleBar,0,AccConst.EVENT_OBJECT_REORDER);
				Accessibility.sendEvent(titleBar,0,AccConst.EVENT_OBJECT_DESTROY);
				Accessibility.sendEvent(titleBar,0,AccConst.EVENT_OBJECT_LOCATIONCHANGE);
				Accessibility.sendEvent(titleBar,0,AccConst.EVENT_OBJECT_PARENTCHANGE);
				Accessibility.sendEvent(titleBar,0,AccConst.EVENT_OBJECT_HIDE);
				Accessibility.sendEvent(titleBar,0,AccConst.EVENT_SYSTEM_FOREGROUND);
				if (systemManager.stage.focus)
					Accessibility.sendEvent(systemManager.stage.focus,0,AccConst.EVENT_OBJECT_FOCUS);

				break;
			}

			case "creationComplete":
			{
				master.$visible = true;

				titleBar = Alert(master).getTitleBar();

				titleBar.tabIndex = 0;
				Alert(master).alertForm.textField.tabIndex = 0;

   				UIComponent(titleBar).$visible = true;

				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_SYSTEM_DIALOGSTART);
				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_OBJECT_REORDER);
				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_OBJECT_CREATE);
				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_OBJECT_LOCATIONCHANGE);
				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_OBJECT_PARENTCHANGE);
				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_OBJECT_SHOW);
				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_SYSTEM_FOREGROUND);
				Accessibility.sendEvent(titleBar, 0, AccConst.EVENT_OBJECT_FOCUS);
				Accessibility.sendEvent(Alert(master).alertForm.defaultButton, 0, AccConst.EVENT_OBJECT_FOCUS);

				break;
			}
		}
	}
}

}