Events not removing

programming flash
1

Hi,

I have added an event “changing” to a List component and when I am trying to remove the same, its not removing. Following is the code.


<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
               xmlns:s="library://ns.adobe.com/flex/spark"
               xmlns:mx="library://ns.adobe.com/flex/mx">
    
    <fx:Declarations>
        <!-- Place non-visual elements (e.g., services, value objects) here -->
    </fx:Declarations>
    
    <fx:Script>
        <![CDATA[
        
        import spark.events.*;
        
        private function preventSelection():void
        {
            
        }
        
        private function removeHandler():void
        {
            ExternalInterface.call('console.log', cb.hasEventListener(IndexChangeEvent.CHANGING));
            cb.removeEventListener(IndexChangeEvent.CHANGING, preventSelection);
        }        
        
        ]]>
    </fx:Script>
    
    <s:layout>
        <s:VerticalLayout />
    </s:layout>
        
    <s:List id="cb" labelField="name" changing="preventSelection()"></s:List>
    <s:Button id="btn1" label="Remove Event" click="removeHandler()"></s:Button>
    
</s:Application>

When I click the button, the first time I see “true” as output in console which is correct since the event is added, but I see the same “true” as output even though when I click the button again and again. So the fact is that the event is not removed. I tried to inspect the issue and generated actionscript and what I see is the below code (only required code part is added)


private function _Main_List1_i() : spark.components.List
{
    var temp : spark.components.List = new spark.components.List();
    temp.labelField = "name";
    temp.addEventListener("changing", __cb_changing);
    temp.id = "cb";
    if (!temp.document) temp.document = this;
    cb = temp;
    mx.binding.BindingManager.executeBindings(this, "cb", cb);
    return temp;
}

public function __cb_changing(event:spark.events.IndexChangeEvent):void
{
    preventSelection()
}

Then in the application, I have changed to remove the “__cb_changing” handler instead of “preventSelection”.


private function removeHandler():void
{
            ExternalInterface.call('console.log', cb.hasEventListener(IndexChangeEvent.CHANGING));
            cb.removeEventListener(IndexChangeEvent.CHANGING, __cb_changing);
}

Now I am able to see “false” from second time onwards which is expected behaviour. **So is this a bug? **

Files are attached for your reference, please add your view.