Transfer RadListBoxItems with ItemTemplates

HOW-TO

Transfer RadListBoxItems with ItemTemplates, evaluated from the datasource.

SOLUTION

When the values from the attributes(assigned from the DataItem) are used to be evaluated in the ItemTemplate in the following manner,

ASP.NET

<ItemTemplate>
<asp:Label ID="Label1" runat="server" Text='<%# DataBinder.Eval(Container, "Attributes[\"ContactName\"]")%>'></asp:Label>
<asp:Label ID="Label2" runat="server" Text='<%# DataBinder.Eval(Container, "Attributes[\"City\"]")%>'></asp:Label>
</ItemTemplate>

the DataBind() method should be explicitly called for each RadListBoxItem, when a transfer operation is performed. This is needed, because the DataItem is nullified, once the datasource is bound to the SourceListBox. The appropriate event-handler for implementing the above is the OnTransferred event handler:

C#

protected void SourceListBox_Transferred(object sender, RadListBoxTransferredEventArgs e)
{
      foreach (RadListBoxItem item in e.Items)
      {
         item.DataBind();
      }
   }

VB

Protected Sub SourceListBox_Transferred(ByVal sender As Object, ByVal e As RadListBoxTransferredEventArgs)
    For Each item As RadListBoxItem In e.Items
        item.DataBind()
    Next
End Sub

A sample project that demonstrates the approach can be found attached here