Radcombobox client validation being triggered on scroll

[Soumya Kommireddi]

I have a radcombox with custom validator for checking if any item is selected in the list; I have virtual scrolling enabled. When I search for items containing some text, the items are populating in the combobox and if there are many items, the scroll bar is showing. When I select the scroll down arrow , the validation is getting triggered. Ideally it should not as I am just scrolling. The validation should only trigger when I do not select an item in the radcombobox and I lose control focus. Is this a bug in telerik?

<telerik:RadComboBox ID="ListSelect" runat="server" Width="192px" EnableLoadOnDemand="true"      ShowMoreResultsBox="true" EnableVirtualScrolling="true" WebServiceSettings-Path="../../ws/AutoSuggest/AutoSuggest.asmx"  AllowCustomText="true" Filter="Contains" OnClientItemsRequesting="SearchAutoSuggest"      WebServiceSettings-Method="GetResults" OnClientSelectedIndexChanged="SelectAutoSuggestValue" AutoPostBack="false" MaxHeight="400px" OnClientDropDownOpening="selectText" MarkFirstMatch="true"  OnClientItemsRequested="highlightText" OnClientDropDownOpened="highlightText"   >
  </telerik:RadComboBox>
                              
                                <asp:CustomValidator ID="Validator_PatientGroupSelect" runat="server" ControlToValidate="ListSelect" ClientValidationFunction="checkValidSelection" />

[Princy]

Hi,

Try the following Javascript to achieve your scenario.

JS:

<script type="text/javascript">
 var flag = 1;
 function selectText(sender, args)  // OnClientDropDownOpening
 {
  flag = 0;
  //Your code
 }
 function OnClientDropDownClosed(sender, args)
 {
  flag = 1;
 }
 function checkValidSelection(sender, args)
 {
  if (flag == 1)
  {
   //Your code
  }
  else
  {
    return;
  }
 }
</script>

Hope this helps.

Thanks,
Princy.

[Soumya Kommireddi]

The solution would solve the problem, but in my opinion it seems like a bug in radcombobox control. Client validation should not be triggering on scroll right? What do you think?

[Dimitar Terziev]

Hello,

The validation is triggered when a callback or a postback is being made to the server. In your particular scenario a request (callback) for items is being made whenever the drop-down is scrolled since the following properties are being set: ShowMoreResultsBox="true" EnableVirtualScrolling="true".

Greetings,
Dimitar Terziev
the Telerik team