Problem about importing class

Question

Hello,
i have this code.
<!-- NameProject.mxml -->
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="
http://www.adobe.com/2006/mxml"
xmlns:my="components.*" width="100%" height="100%">
<mx:Script>
<![CDATA[
import lib.User;
public var u:User = new User();
trace(u.say("hello world"));
]]>
</mx:Script>
</mx:Application>
<!-- /lib/User.as -->
package lib{
public class User{
public function say(s:String):String{
return s;
i get this error:
1120 Access of undefined property
Why??
thanks so much

Answer 1

You have this Script block in your code:
<mx:Script>
<![CDATA[
import lib.User;
public var u:User = new User();
trace(u.say("hello world"));
]]>
</mx:Script>
The trace statement is just "floating" in there - it must be
in a function. When do you want this trace executed? For example,
if you want to display it when the Application dispatches its
creationComplete event, then add a creationComplete event handler
to the Application tag and then write the function to handle the
event in the Script block:
<mx:Application ... creationComplete="initApp()">
<mx:Script>
<![CDATA[
import lib.User;
public var u:User = new User();
private function initApp() : void {
trace(u.say("hello world"));
]]>
</mx:Script>
Now the trace statement appears in a function so you will not
get the error.