using the GongSolutions.Wpf.DragDrop library, not able to drop

I am using the GongSolutions.Wpf.DragDrop library. But i implement everything , just simple so i can reorder my listbox, my code:

ListBox ItemsSource="{Binding AvailableQuestions}" 

  dd:DragDrop.IsDragSource="True" 
  dd:DragDrop.IsDropTarget="True" Margin="0,0,0,184" Background="#FF0BCE0B" />

AvailableQuestions is a开发者_StackOverflow list of Strings

but i am not able to drag and drop them .. Someone who see what i am doing wrong?

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You need to make sure your binding collection 'AvailableQuestions' is an ObservableCollection type. That should do the trick.