Calling several objects in document extensions

[#1]

Hello,

I'm currently working on a project where I'm creating a document extension to manage a menu with 2 listboxes.

Lisbox1 = Main menu

Listbox2 = Sub menu

As it's a menu we are managing, we prefer to use a document extension.

We have done the necessary build for document extensions..

But we're encountering difficulties with the Script.js - we cannot successfully call 2 objects (LB01 and LB02) with our script.

Here below the content of the script:

var mydoc = Qv.GetCurrentDocument();
var myObjLvl_1 = mydoc.GetObject("LB01"); // this is the first listbox on the document test.qvw
//var myObjLvl_2 = mydoc.GetObject("LB02"); // this is the second listbox on the same document
Qva.AddDocumentExtension('test', function(){
});

This script successfully calls LB01. When I uncomment the call LB02, nothing works anymore!

So my questions are:

     - why isn't it working?

     - in the Javascript API guide, I don't understand the explanations around the function GetObject

          http://qlikcommunity.s3.amazonaws.com/misc/symbols/Qv.Document.html#GetObject

     - is there an equivalent for Qv.InitWorkBench function for document extension?

Any help would be much appreciated.