Empty page if i put a RangeValidator on a userControl bound to a listbox

Feb 19, 2009 at 4:02 PM
Edited Feb 19, 2009 at 4:04 PM

After a quick google search for range validation i'll found this project.

After I add a RangeValidator to a UserControl which is bound to a list box
I got an empty page. The browser tell me

Sys.InvalidOperationException: ManagedRuntimeError error #4004 in control 'Xaml1': System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt. bei Silverlight.Validators.ValidatorBase.FindManager(UserControl c, String groupName) bei Silverlight.Validators.ValidatorBase.element_Loaded(Object sender, RoutedEventArgs e) bei System.Windows.CoreInvokeHandler.InvokeEventHandler(Int32 typeIndex, Delegate handlerDelegate, Object sender, Object args) bei MS.Internal.JoltHelper.FireEvent(IntPtr unmanagedObj, IntPtr unmanagedObjArgs, Int32 argsTypeIndex, String eventName)

It work fine if i put it on the page which contains the listBox.

Any idea to fix this ?

Thanks in advance