How to pass parameter to Custom Component written in ActionScript

Question

I have a custom component written in ActionScript. It has constructor which is expecting some arguments.

I want to include that custom component in mxml like this,

Main.mxml

...
<custom:CustomActionScriptComponent/>  // Error line ..
..

But, it shows me an error saying

Error 1136: Incorrect number of arguments.  Expected 1.

How to pass parameter in MXML file, to that custom ActionScript component?

MXML requires that classes have no required constructor parameters, and there is no way to pass them one. By setting some other property, you can dictate behavior in the instance — Exhausted, Nov 27 '11 at 14:19

score 5 · Accepted Answer · answered Nov 27 '11 at 07:19

As tags, MXML does not support class constructors.

Per your ActionScript class, you could allow default initialization of the parameter:

    public function CustomActionScriptComponent(parameter:Object=null)
    {
        super();
    }

Then implement a creation complete event handler in your MXML:

<?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"
               creationComplete="creationCompleteHandler(event)">

    <fx:Script>
        <![CDATA[
            import mx.events.FlexEvent;

            protected function creationCompleteHandler(event:FlexEvent):void
            {
                customActionScriptComponent.parameter = {};
            }
        ]]>
    </fx:Script>

    <custom:CustomActionScriptComponent id="customActionScriptComponent" />

</s:Application>

score 0 · Answer 2 · answered Dec 01 '11 at 14:56

Well, actually it is possible, but for this purpose you need to change the compiler. I've read article about this, but it's on russian and I didn't find any english one. I didn't make it by myself, but guys were able to write code like this:

<?xml version="1.0"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
               xmlns:s="library://ns.adobe.com/flex/spark">
    <fx:Declarations>
        <Timer xmlns="flash.utils.*" new="1000, 1" />
    </fx:Declarations>
</s:Application>

where new contains constructor arguments.

Anyway, I provide a link to the article for someone who will be interested in this http://habrahabr.ru/blogs/Flash_Platform/128703/

How to pass parameter to Custom Component written in ActionScript

2 Answers2

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