NullReferenceException when GroupDescriptor is added

[Jose]

When I try to add the GroupDescriptor always got Null exception error.

I using ObservableCollection<>  from a ViewModel class as ItemSource on the Jumplist and everything works as expected until I add the groupdescriptor (the PropertyName is one of the items of the Collection)

Any ideas how to handle this issue?

Thanks

[Deyan]

Hi Jose,

Thanks for contacting us.

We are currently not aware of similar issues in RadJumpList. We are constantly using this control in our examples and it works as expected when adding group descriptors.

Could you please share some further details on your scenario. It will be very helpful if you manage to create a small WP7 application that reproduces the case so that we can directly see what goes wrong.

Please note that in order to be able to attach your sample project, you will have to open a new support ticket.

Thanks for your time.

Best wishes,
Deyan
the Telerik team

[Jose]

Thanks for your quick response.
Later this afternoon I'll create an small app to reproduce the error.

Do I need to use the attach file option here to send you the project?

 

Jose

[Deyan]

Hello Jose,

Thanks for writing back.

You should open a new support ticket in order to be able to attach a file.

You are not able to attach files here in the forum.

Looking forward to receiving your demo app.

Kind regards,
Deyan
the Telerik team

[Jose]

I created the support ticket.
Ticket ID: 452891

[Deyan]

Hi Jose,

Thanks for writing back.

We have identified the reason for the undesired behavior that you experience and have logged this in our TODO system for fixing.

Here is a workaround you could use to overcome this exception:

public MainPage()
{
      this.InitializeComponent();
      GenericGroupDescriptor<TwitterItem, string> groupDesc = new GenericGroupDescriptor<TwitterItem, string>();
      groupDesc.KeySelector = (TwitterItem element) => { return element.UserName; };
      radDataBoundListBox1.GroupDescriptors.Add(groupDesc);
}

Basically, what you need to do is use a GenericPropertyDescriptor and directly return the value of the key you would like to group by.

Please refer to the support ticket you sent is regarding the same topic for further details.

Best wishes,
Deyan
the Telerik team

[Jose]

Thanks...it works...

Jose