OnClientItemsRequesting event for RadDropDownTree

[Tauqir]

I am using the MinFilterLength property for filtering items in the RadDropDownTree. Assume the MinFilterLength property is set to 3.
If I now enter 3 characters, the results are filtered correctly. However, if I delete a character, the results are not reset.
How can I achieve this?
I searched online, and found a possible solution here: http://www.telerik.com/community/forums/aspnet-ajax/combobox/hide-disable-the-loading-text-on-itemsrequested.aspx.
However, RadDropDownTree does not have a OnClientItemsRequesting event. Which event can I use to achieve the same behavior?
Thanks.

[Boyan Dimitrov]

Hello,

Your observations are absolutely correct and we will include a fix for this issue in our upcoming service pack release.  In the meantime you can use this workaround
//markup code

<telerik:RadDropDownTree ID="RadDropDownTree1" runat="server" DefaultMessage="Select location" Skin="Default"
       EnableFiltering="true" FilterSettings-Highlight="Matches" FilterSettings-MinFilterLength="3">
   </telerik:RadDropDownTree>

//JavaScript

<script type="text/javascript">

           var isBackspacePressed = false;

           function pageLoad() {

               $find("RadDropDownTree1")._manager._shouldFilter = function (text) {

                   var shouldFilter = ((text.length >= this._minFilterLength || (text == "" && this._minFilterLength == 1)) || isBackspacePressed);

                   isBackspacePressed = false;

                   return shouldFilter;

               }

               $find("RadDropDownTree1")._manager._onFilterKeyUp = function (e) {
                   //debugger

                   var text = e.target.value,
                       key = Sys.UI.Key,
                       keyCode = e.keyCode || e.which;



                   if (keyCode == key.backspace) {
                       isBackspacePressed = true;
                   }
                   else {
                       isBackspacePressed = false;
                   }

                   switch (keyCode) {
                       case 16: // shift
                       case 17: // ctrl
                       case 18: // alt
                       case key.home:
                       case key.end:
                       case key.enter:
                       case key.tab:
                           e.stopPropagation();
                           e.preventDefault();
                           break;
                       case key.left:
                       case key.right:
                       case key.up:
                           break;
                       case key.down:
                           this._focusNextElement(e);
                           break;
                       case key.pageUp:
                       case key.pageDown:
                           break;
                       case key.esc:
                           break;
                       default:
                           this._handleFiltering(text);
                           break;
                   }
               }
           }

       </script>

Regards,
Boyan Dimitrov
Telerik