Calling JavaScript function from Flex 4 web application - apache-flex

Question

I need to call javascript function from Flash 4 based web application. When I run it in Debug mode it runs perfectly but when I make release build or run same application on other machine it does not call JavaScript function.
For testing I am just calling sample Alert function of JavaScript. Can someone help me what I am missing ?
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="vertical" initialize="application1_initializeHandler(event)"
verticalAlign="middle"
backgroundColor="white">
<mx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.events.FlexEvent;
public function btnLogin_click():void
{
var s:String;
if (ExternalInterface.available)
{
ExternalInterface.call("alert", "Hello World!");
}
else
{
Alert.show("External interface not available");
}
trace(s);
}
protected function application1_initializeHandler(event:FlexEvent):void
{
flash.system.Security.allowDomain("always");
}
]]>
</mx:Script>
<mx:Form>
<mx:FormItem>
<mx:Button id="btnLogin" label="Login" click="btnLogin_click()" />
</mx:FormItem>
</mx:Form>
</mx:Application>

Answer 1

Well, firstly, make sure JavaScript on your testing machine is turned on and then also make sure you are adding your JavaScript file/code after adding swfobject.js file.
I had similar problem but it worked out when I moved swfobject.js at the top of all js includes.

Answer 2

Have you tried a test like (Flex):
ExternalInterface.call("alertFn");
And JS:
function alertFn() {
alert("hello world");
}
?
I've never tried an ExternalInterface call to a native JS function like "alert"...

Answer 3

After digging out the error code 2060 through
Alert.show(e.message)
I figured out that for some reason ExternalInterface.call doesn't work on a file:// and needs http(s)://
So, anybody who is facing this problem, get your yourself a webserver(Apache) or a GAE for testing these kinds of things and save yourself from the "Extreme time wastage":
I was having endless hours of problems using file:// with the Flex
AJAX Bridge.
The AJAX code would fail silently during the SWF initialization
callbacks to the AJAX code. I would then have null values for all of
the SWF root elements.
As soon as I installed a web server and started using http:// localhost
everything worked perfectly.
Extreme time wastage :(

Answer 4

test.mxml
..........
protected function bt1_clickHandler(event:MouseEvent):void
{
// TODO Auto-generated method stub
ExternalInterface.call("callUnity");
}
.js
....
function callflex(){
alert("got it");
}