Telerik RAD Ajax Combobox becomes non responsive after postback

[Nikhil Vaghela]

We are using latest RAD Combobox and Rad Checkbox in our SharePoint 2010 Visual Web Part.

We have two node in tree view. We have one panel which contains two RAD Combo boxes.  When firs node is selected/chcecked then the panel is made visible and shown.On second node click the panel is made hidden. 
On tree node click 

We are facing two issues

1.  On tree view's FIRST node click the page does postback (only once, subsequent tree view node click does not post back, it does partial postback through ajax) 
2.  If first node is clicked where panel is made visible then the RAD Combo box seems to be working , but if after the page load the second node was clicked and then the first node was click, the RAD Combobox becomes non responsive. nothing happens on click or the combo-box. 

Would appreciate any urgent help.

[Nikhil Vaghela]

By the way I have a sample project were we are able to reproduce these issues, how do i upload that as attachment here ??

[Kalina]

Hello Nikhil Vaghela,

It is known that SharePoint has issues when the RadAjaxManager is declared at markup in a user control.
I am suggesting you add the RadAjaxManager at OnInit event of the WebPart and then at CreateChildControls add the AjaxSettings manually:

RadAjaxManager ajaxmgr;

protected override void OnInit(EventArgs e)
{
    base.OnInit(e);
    ajaxmgr = new RadAjaxManager();
    Page.Items.Add(typeof(RadAjaxManager), ajaxmgr);
    Page.Form.Controls.AddAt(0, ajaxmgr);

}

protected override void CreateChildControls()
{
    Control control = Page.LoadControl(_ascxPath);
    Controls.Add(control);
    // Finding the ASP.Panel and the DropDownList that is nested inside
    Panel panel = control.FindControl("pnlCars") as Panel;
    DropDownList dropDownList = panel.FindControl("dropDownList") as DropDownList;
    // Finding the label
    Label label = control.FindControl("lblMessage") as Label;
    ajaxmgr.AjaxSettings.AddAjaxSetting(dropDownList, label);
}

Regards,
Kalina
the Telerik team