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

package gov.va.med.edp.widget
{
        import flash.events.Event;
        import flash.events.FocusEvent;
        
        import gov.va.med.edp.util.AccessibilityTools;
        import gov.va.med.edp.widget.accessibility.AccessibleLabelAccImpl;
        import gov.va.med.edp.widget.accessibility.IAccessibleComponent;
        
        import mx.controls.Label;
        import mx.managers.IFocusManagerComponent;
       
    /** 
     * This class extends the mx Label class  in order to make them focusable.
     * For a user with a screen reader, if the image is critical to the application
     * you will need to have some way to communicate a summary of the image's information
     * to a screen reader.
     *
     * You can check if a screen reader is being used to make this component
     * behave like the standard label component so a user that does not need
     * accessibility features will not see the tooltips or be able to tab
     * to label components.
     */
        public class AccessibleLabel extends Label 
            implements IFocusManagerComponent, IAccessibleComponent 
        {
                /**
            *  @private
            */
                private var _accessibleText:String = "";
                                
           /**
       *   Constructor
       */
                public function AccessibleLabel() 
                {
                        super();
                }
                
                /**
             *  @public
             *  Method to set accessible text.
             */
                public function set accessibleText(s:String):void
                {
                        _accessibleText = s;
                        dispatchEvent(new Event("accessibleTextChanged"));
                }
                
                /**
             *  @public
             *  Method to get accessible text.
             */
                public function get accessibleText():String
                {
                        return _accessibleText;
                }
                
                /** 
                 * The properties are set on creation complete.  
                 * accessibilityProperties will be guaranteed 
                 * to be accurate at this point 
                 * and the accessibility changes
                 * can be made accordingly. 
                 **/
                override protected function commitProperties():void
                {
                        
                        if ((accessibilityProperties != null) 
                           && (AccessibilityTools.isAccessibilityActive()))  
                        {
                                focusEnabled = true;
                                tabEnabled = true;
                                accessibilityImplementation = new AccessibleLabelAccImpl(this);
                                setStyle("focusThickness", 2);
                                
                        }
                        else 
                        {
                                focusEnabled = false;
                                tabEnabled = false;
                                removeEventListener(FocusEvent.FOCUS_IN, focusInHandler);
                                removeEventListener(FocusEvent.FOCUS_OUT, focusOutHandler);
                        }
                }
                
                /**
                 * @protected
                 *  Method that handles focus in events 
                 */
                override protected function focusInHandler(event:FocusEvent):void 
                {
                        _accessibleText = (_accessibleText == "" ? text : _accessibleText); 
                   
                    // revised by jtorreno 07/29/2008
                    // fix for null error exception if component is null 
                    if ((focusManager != null) && (focusManager.getFocus() != null))
                    {
                        drawFocus(true);
                    }   
                   
                        event.stopPropagation();
                }
                
                                
        }
}