Populate and clear list in a task

Hi Kevin,

I tried to use a "lock" in the method FillCollection :

        public static void FillCollection(DynamicCollection<T> dc)
        {
            var obj_lock = new object();
            lock (obj_lock)
            {
               dc.Clear();
               // Populate the list in a loop ...
            }
        }

Not sure it is the good way because I still have the same issues. What do you think ?