source: EDIS/trunk/java/tracking-ui-core/src/main/flex/gov/va/med/edp/widget/accessibility/LinkButtonTabBarAccImpl.as@ 1227

package gov.va.med.edp.widget.accessibility
{
        import gov.va.med.edp.widget.LinkButtonTab;
        import gov.va.med.edp.widget.LinkButtonTabBar;
        
        import mx.accessibility.TabBarAccImpl;
        import mx.core.UIComponent;
    import mx.core.mx_internal;

    use namespace mx_internal;

    public class LinkButtonTabBarAccImpl extends TabBarAccImpl
        {
        private static const MAX_NUM:uint = 100000;

        /**
                 *  @private
                 *  Static variable triggering the hookAccessibility() method.
                 *  This is used for initializing LinkButtonTabBarAccImpl class to hook its
                 *  createAccessibilityImplementation() method to LinkButtonTabBar class
                 *  before it gets called from UIComponent.
                 */
                private static var accessibilityHooked:Boolean = hookAccessibility();
        
                /**
                 *  @private
                 *  Static method for swapping the createAccessibilityImplementation()
                 *  method of LinkButtonTabBar with LinkButtonTabBarAccImpl class.
                 */
                private static function hookAccessibility():Boolean
                {
                        LinkButtonTabBar.createAccessibilityImplementation =
                                createAccessibilityImplementation;
        
                        return true;
                }
                
                /**
                 *  @private
                 *  Method for creating the Accessibility class.
                 *  This method is called from UIComponent.
                 *  @review
                 */
                mx_internal static function createAccessibilityImplementation(
                                                                        component:UIComponent):void
                {
                        component.accessibilityImplementation =
                                new LinkButtonTabBarAccImpl(component);
                }
        
                /**
                 *  Method call for enabling accessibility for a component.
                 *  This method is required for the compiler to activate
                 *  the accessibility classes for a component.
                 */
                public static function enableAccessibility():void
                {
                }
                
                /**
                 *  Constructor.
                 *
                 *  @param master The UIComponent instance that this AccImpl instance
                 *  is making accessible.
                 */
                public function LinkButtonTabBarAccImpl(master:UIComponent)
                {
                        super(master);
                }

                /**
                 *  @private
                 *  method for returning the name of the Tab
                 *  which is spoken out by the screen reader.
                 *
                 *  @param childID:uint
                 *
                 *  @return Name:String
                 */
                override protected function getName(childID:uint):String
                {
                        if (childID == 0)
                                return "View Selector Panel";
        
                        var name:String;
        
                        var tabBar:LinkButtonTabBar = LinkButtonTabBar(master);
                        // Assuming childID is always ItemID + 1
                        // because getChildIDArray is not always invoked.
                        var index:int = childID < MAX_NUM ?
                                                        childID - 1 :
                                                        childID - MAX_NUM - 1;
                        //With new version of JAWS, when we add a new child, we get nonsense number
                        //not caught above. In this case, return last tab.
                        if (index > tabBar.numChildren || index < 0)
                                index = tabBar.numChildren -1;
                        var item:LinkButtonTab = LinkButtonTab(tabBar.getChildAt(index));
        
                        name = item.label;
        
                        if (index == tabBar.selectedIndex)
                                name += " Tab, Active";
                        else
                                name += " Tab";
        
                        return name;
                }

        }
}