To work this around, you can create a custom DataFormComboBoxField and override the default value of the SelectedIndex property.
public class MyComboBoxField : DataFormComboBoxField
{
static MyComboBoxField()
{
DataFormComboBoxField.SelectedIndexProperty.OverrideMetadata(typeof(MyComboBoxField), new PropertyMetadata(-1));
}
}
Regards,
Martin Ivanov
Progress Telerik
When you define a DataFormComboBoxField and set its SelectedIndex initial value to 0, the value is not present in the field.