[Solved] Combobox items added after binding not getting displayed in dropdown

[Siva]

Hi there 

I am using the following code to load RadComboBox and insert the RadComboBox with a  text "select item" at the top which is fairly basic, but I am unable to see the text "select item" added when clicking the dropdown.  Please Advice!

[Code and error image attached]

Thanks

Siva

        <telerik:RadComboBox  ID="RadComboBox1" runat="server" Height="190px" Skin="Office2007"
                        Width="300px" MarkFirstMatch="true"  NoWrap="true" DropDownWidth="420px" EnableLoadOnDemand="true" HighlightTemplatedItems="true"
                        ItemRequestTimeout="500">
                        <HeaderTemplate>
                            <ul>
                                <li class="col1">Company Name</li>
                            </ul>
                        </HeaderTemplate>
                        <ItemTemplate>
                            <ul>
                                <li class="col1"><%# DataBinder.Eval(Container.DataItem, "CompanyName") %></li>
                            </ul>
                        </ItemTemplate>
                    </telerik:RadComboBox>

  Dim sql As String = "SELECT * from Customers"
        Dim adapter As New SqlDataAdapter(sql, ConfigurationManager.ConnectionStrings("NorthwindConnectionString").ConnectionString)

        Dim dt As New DataTable()
        adapter.Fill(dt)
        RadComboBox1.DataTextField = "CompanyName"
        RadComboBox1.DataValueField = "City"
        RadComboBox1.DataSource = dt
        RadComboBox1.DataBind()

        RadComboBox1.Items.Insert(0, New Telerik.Web.UI.RadComboBoxItem("Select Item", "None"))

[Schlurk]

Try to add this during the DataBound or PreRender event and see if that fixes it.

DataBound:

protected void RadComboBox1_DataBound(object sender, EventArgs e)
{
         RadComboBox1.Items.Insert(0, New Telerik.Web.UI.RadComboBoxItem("Select Item", "None"))
}

PreRender:

protected void RadComboBox1_PreRender(object sender, EventArgs e)
{
         RadComboBox1.Items.Insert(0, New Telerik.Web.UI.RadComboBoxItem("Select Item", "None"))
}

[Veselin Vasilev]

Hi Siva,

You have defined an ItemTemplate which renders the CompanyName value from the dataItem, but the "Select Item" does not have a dataItem property - so it is not rendered.
I am a bit curious why do you need to use a template in your case since you only show one text field?
You can achieve that behavior without templates very easy - just remove the ItemTemplates and the look should be the same.

If you still want to use templates - you can do the following:

<ItemTemplate>
  <ul>
     <li class="col1"><%# Container.DataItem != null ? DataBinder.Eval(Container.DataItem, "CompanyName") : "Select Item" %></li>
  </ul>
</ItemTemplate>

RadComboBox1.Items.Insert(0, New Telerik.Web.UI.RadComboBoxItem("Select Item", "None"))
RadComboBox1.Items(0).DataBind()

Hope this helps.


Greetings,
Veselin Vasilev
the Telerik team

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