Accessing Selected Items in a Listbox using Javascript

[#1]

I am trying to access a listbox control in my QVW from my ASPX page and find out if it has any items selected. In VBScript you might see code similar to :

set LB=ActiveDocument.GetSheetObject("LB76")

set boxfield = LB.GetField

if boxfield.GetFieldFlags.HasSelection then

  FS = 1

...

Does anyone know the equivalent code in Javascript to get find out if a listbox control has a selected item(s)?

[#2]

Hi bkirkman,

You can get a reference to a listbox using our AJAX API like this:

     function init() {

           var myListBoxObject = this.GetQvObject("LB02", function(){});

           alert(myListBoxObject.Name + " " + myListBoxObject.mode);

     }

     Qva.BodyOnLoadFunctionNames.push('init');

That example code is as if you were in an extension object. In v11 you will be able to do this sort of thing from a document extension (see the beta forum for more details on document extensions).

Once you have the reference to the listbox object you can use the GetSelected() method.

-Dan

[#3]

Dan,

Ok, this is what I've tried so far and any comments/hints are welcome.

The goal is to get the selected items from a QV Workbench Listbox object in my .net web application. I need to do some validation on a button click that involves the Listbox.

So here is my javascript function that gets called on the button click:

function OpenmodalCheckout() {

var selectedallrs = qva.GetQvObject("LB56", GetSelectedRateSheets, this);

if(selectedallrs)

{

     var selectedCount = selectedallrs.length;

}

if(selectedCount >0)

{

  .. do stuff ..

}

return false;

}

And the other function on the getqvobject call

function

GetSelected() {

var selrs = this.Data.GetEnabled();

return selrs;

}

What happens though is that the GetSelected method gets called AFTER the OpenModalCheckout gets called so my selectedCount is undefined. Why is that?

[#4]

I got this to work but not as I expected.

I had to add this code into my Init function so that I get the listbox I want and then get the selected items from the object then store them in a ASP.NET hiddenfield so I can access them during the web page's lifecycle. Trying to just access the control in a javascript method on say a button click always returned a null object.

This seems to be a hack way to work with these objects so can anyone tell me how to access the QlikView object on say a button click event in my javascript instead of having to always do this in my Init function?

[#5]

Don't know if this will help you, but see post here... http://community.qlik.com/message/142080#142080

[#6]

var listboxes = {};  // will be used as a collection of list boxes.

function Init() {

     listboxes["LB1"] = qva.GetQvObject("LB1", function () {

     });

     listboxes["LB2"] = qva.GetQvObject("LB2", function () {

     });

}

Qva.BodyOnLoadFunctionNames.push("Init");

...

function dosomething(listboxId) {

     var selectedData = listboxes[listboxId].QvaPublic.Data.GetSelected();

     ... do something...

}

...

<div id="bla1" onclick="dosomething('LB1');">get selected from lb1</div>

<div id="bla2" onclick="dosomething('LB2');">get selected from lb2</div>