What's wrong in this XML command?

1

[SIZE=1][SIZE=1]hi[/SIZE]
[SIZE=1]here’s the external XML file(simplified):[/SIZE]


[SIZE=1]<skills>[/SIZE]
[SIZE=1]<skill ID="1">......</skill>[/SIZE]
[SIZE=1]<skill ID="2">......</skill></skills>[/SIZE]

[SIZE=1]when I import it, everything’s fine, I put it in a variable named skills too[/SIZE]
[SIZE=1]when I use this, I get an error:[/SIZE]
[SIZE=1]

public function getSkillInfo():String{

[/SIZE]


[SIZE=1] var the_info=skills.*[0].@ID[/SIZE]
[SIZE=1]return the_info[/SIZE]
[SIZE=1]}[/SIZE]
[SIZE=1]//later: getSkillInfo()[/SIZE]

[SIZE=1]the error:[/SIZE]
[SIZE=1]TypeError: Error #1009: Cannot access a property or method of a null object reference.[/SIZE]

[SIZE=1]what’s wrong?[/SIZE]
[/SIZE]

edit:

I just found out by tracing skills that it returns null, but why?:

 
private function completeListener(e:Event) {
skills=new XML(loadFile.data)
trace(skills.toString());//everything ok
}
public function getSkillInfo(){
trace(skills);//returns null
}