Conditional handler : Event Handler « Event « Flex






Conditional handler

Conditional handler
            


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<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
    xmlns:mx="library://ns.adobe.com/flex/mx"
    xmlns:s="library://ns.adobe.com/flex/spark"
    initialize="initApp(event)">
    <s:layout>
        <s:VerticalLayout />
    </s:layout>
    <fx:Script>
         
        import mx.controls.Alert; 
        private function initApp(e:Event):void { 
            cb1.addEventListener(MouseEvent.CLICK, handleCheckBoxChange); 
            b1.addEventListener(MouseEvent.CLICK, logAction); 
        } 
        private function handleCheckBoxChange(e:Event):void { 
            if (cb1.selected) { 
                b1.addEventListener(MouseEvent.CLICK, logAction); 
                ta1.text += "Added log listener." + "\n"; 
            } else { 
                b1.removeEventListener(MouseEvent.CLICK, logAction); 
                ta1.text += "Removed log listener." + "\n"; 
            } 
        } 
        private function performAction(e:Event):void { 
            Alert.show("You performed the action."); 
        } 
        private function logAction(e:Event):void { 
            ta1.text += "Action performed: " + e.type + ".\n"; 
        } 
      
    </fx:Script>
    <s:Button label="Perform Action" id="b1"
        click="performAction(event)" />
    <s:CheckBox id="cb1" label="Log?" selected="true" />
    <s:TextArea id="ta1" height="200" width="300" />
</s:Application>

   
    
    
    
    
    
    
    
    
    
    
    
  








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