Update
After a bit of investigating. What seems to be the issue is that the SelectedValue/SelectedItem is occurring before the Item source is finis
I had the same problem. The thing is. The selected item doesnt know which object it should use from the collection. So you have to say to the selected item to use the item from the collection.
public MyObject SelectedObject
{
get
{
Objects.find(x => x.id == _selectedObject.id)
return _selectedObject;
}
set
{
_selectedObject = value;
}
}
I hope this helps.