RadListBox help

[rhin]

I have RadLisBox custom scripts and am putting focus on ClientLoad()

Something like

Function OnClientLoad(sender, eventsArgs)

{

var RadListBox = $find('radlistbox.clientid')

RadListBox.on('focus', function (e) {
                var index = $('#' + e.target.closest("li").id).index();
                var item = radListControl.get_items().getItem(index);
                if (item) {
                    radListControl.clearSelection();
                    radListControl._activateItem(item, true);
                    item.set_selected(true);
                }
            });

}

item.set_selected(true) give me an error on _updatevalidationfield()

Can I override this code somehow?

 

Edit: There is custom validator attached to this. Think the error is coming from it

EDIT2: I think I figured it out (maybe?). The items within the control are disappearing after some time - probably postback event from validator. I had sort of singleton in place cause I did not need to update the instance of the control. After removing it at least at this point it seems ok. 

 

[Attila Antal]

What would you like to achieve with the focus? The code is incorrect and is erroring out.

[rhin]

it is a pseudo code just giving idea what I am going for (posting 2000 lines code is not a good idea). But yes, I had singleton for selecting the instance of the control however based on research and trials my edit 2 turns out to be correct - on postback the items in the control are returning null. That was fixed by removing the singleton.

[Attila Antal]

Hello Rhin,

So basically there are 3 things you will need to take into account. The Telerik JavaScript object, the HTML element, and the jQuery object.

function OnClientLoad(sender, eventsArgs) {
    var RadListBox = $find('<%= RadListBox1.ClientID %>'); // This is a Telerik RadListBox object

    var RadListBoxElement = RadListBox.get_element(); // This is the HTML element of the Control

    var $RadListBoxJquery = $(RadListBoxElement); // This is a jQuery object

    // jQuery way of listening to the focus event

    $RadListBoxJquery.on('focus', function (e) {

        // Your logic here

    });
}

 

Telerik & ASP.NET AJAX way of getting client-side reference: Get Client-side Reference to a Control Object

Almost all Telerik objects can return the HTML by calling the .get_element() method. You can use this to pass to the jQuery method.

jQuery requires you to pass an HTML element to its methods: jQuery

Regards,
Attila Antal
Progress Telerik