RadCombobox ajax help needed

[Gregor Suttie]

Hi There

I am using a radcombobox box as below:-

 <telerik:RadComboBox ID="radComboFullname" AllowCustomText="true" runat="server" AutoPostBack="true" SkinID="fullnamesearchdropdown"
                        CausesValidation="False" OnClientItemsRequesting="RequestingHandler" EnableLoadOnDemand="true"
                        HighlightTemplatedItems="true" ItemRequestTimeout="750" DataSourceID="objDSClientSmartSearch"
                        DataTextField="fullname" DataValueField="id" TabIndex="1" OnItemsRequested="radComboFullname_ItemsRequested"
                        OnSelectedIndexChanged="radComboFullname_SelectedIndexChanged"
                        ShowMoreResultsBox="true" MaxLength="100" IsCaseSensitive="false" LoadingMessage="Searching. Please Wait..." >
                    </telerik:RadComboBox>

When the user types more than 2 characters we go off and try to bring back results to display and that works just fine - when niothing is found however we see the text No Matches which is great, but what I need to have happen is for focus to leave this rad combobox from the code behind within :-

protected void radComboFullname_ItemsRequested(object o, Telerik.Web.UI.RadComboBoxItemsRequestedEventArgs e)
{
    if (e.Text.Trim().Length >= 2)
    {
    }
    else
    {
        //move focus off the control
    }
}            

How can i accomplish this?


The javascript we use is also as follows:-
function RequestingHandler(sender, eventArgs) {
            //restrict ajax request until after 2 chars
            if (eventArgs.get_text().length < 2)
                eventArgs.set_cancel(true)
            else
                eventArgs.set_cancel(false);
        }

[Simon]

Hello Gregor Suttie,

You cannot alter the state of the RadComboBox in the ItemsRequested event handler. Even scripts emitted there to the client side will not be executed.

You could achieve this in the client-side ItemsRequested event handler. There you could to the same check for length and focus another element.

Greetings,
Simon
the Telerik team

[Gregor Suttie]

If a user types in rubbish and no results are found - how can I remove focus from the radcombobox so that the event is cancelled and the drop down is hidden - cant seem to do it from OnClientItemsRequested, is there a way to do it within OnClientItemsRequesting?

Thanks
Gregor

 

[Simon]

Hello Gregor Suttie,

You can prevent drop down opening until Items are loaded by handling the client-side DropDownOpening and ItemsRequested events in this way:

var preventDDOpening = true;

function onDropDownOpening(sender, eventArgs) {
    eventArgs.set_cancel(preventDDOpening);
    if (!preventDDOpening)
        preventDDOpening = true;
}

function onItemsRequested(sender) {
    if (sender.get_items().get_count() > 0) {
        preventDDOpening = false;
        sender.showDropDown();
    }
}

As to the focus, you can move it in the else body in the ItemsRequested event handler.

Best wishes,
Simon
the Telerik team