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RadComboBox load data problem

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ComboBox

This is a migrated thread and some comments may be shown as answers.

Sergey asked on 05 Jan 2012, 02:15 PM

Hi,
I have RadComboBox

<telerik:RadComboBox ID="combo" runat="server" OnItemDataBound="ItemDataBound" AllowCustomText="true"  EnableTextSelection="true" EnableEmbeddedBaseStylesheet="true" ChangeTextOnKeyBoardNavigation="true" CollapseAnimation-Type="InCubic" DropDownWidth="298px" EnableScreenBoundaryDetection="true" MarkFirstMatch="true" NoWrap="False" Filter="None" CausesValidation="false" IsCaseSensitive="false" EmptyMessage="--All--" ShowDropDownOnTextboxClick="true" HighlightTemplatedItems="True" EnableLoadOnDemand="True" ShowMoreResultsBox="True" ShowToggleImage="True" EnableVirtualScrolling="True" OnItemsRequested="OnItemRequested" OnClientSelectedIndexChanged="multiSelectedIndexChanged" Height="200px" Width="145px"> </telerik:RadComboBox>

witch use the following methods for data loading:

protected void OnItemRequested(object sender, RadComboBoxItemsRequestedEventArgs e) { IList list = DataSourceFunc != null ? DataSourceFunc(e.Text) : new ArrayList(); if (GetEmptyItem != null && list.Count > 0) { list.Insert(0,GetEmptyItem()); } int itemsPerRequest = ConfigCaller.DropDownPortionSize; int startOffset = e.NumberOfItems; int endOffset = Math.Min(startOffset + itemsPerRequest, list.Count);<br

>            var data = GetPortion(list, Math.Max(0, startOffset - 1), endOffset - Math.Max(0, startOffset - 1));<

br> if (data.Count > 0) { combo.ClearSelection(); combo.DataSource = data; combo.DataBind(); if (!String.IsNullOrEmpty(EmptyClass) && GetEmptyItem != null) { combo.Items[0].Attributes.Add("style", EmptyClass); } } e.Message = list.Count > 0 ? String.Format("Items 1-{0} out of {1}", endOffset, list.Count) : "No matches"; e.EndOfItems = endOffset == list.Count; } private IList GetPortion(IList list, int start, int count) { var result = new ArrayList(); for (int index = 0; index < list.Count; index++) { var item = list[index]; if (index >= start && index < start + count) { result.Add(item); } } return result; }

But when I open it i see only loading message whitch never hides. If i close it and open it again I see all valid items immidetly but still see load message on the top of combobox. I looked on it behavior on such tools like fiddler2 and firebug and pointed out that once opened it sends requests to the server each ~500ms and they returned with 200 ok result and valid response but combobox continue requests sending. I don't have any errors or exceptions on both client and server side and any entries in windows event log. Has anybody the same problems or knows how to fix this strange behaviour or what can it cause?

6 Answers, 1 is accepted

answered on 06 Jan 2012, 03:16 PM

Hello,
This example is not I really need. I need multycolumn combobox loading on demand. And as I understand the only way to do it out-of-the box - use ItemRequested event. Like in this example http://demos.telerik.com/aspnet-ajax/combobox/examples/functionality/multicolumncombo/defaultcs.aspx. It works correct on my local machine and on one test server but on the other servers it cycles and sends data requests one by one each 500ms. Even isolated on the empty page it doesn't works correct. The data returned from the server with each response is correct. What can cause that strange behaviur of the combobox?