public MemMemento CloneMemento(MemMemento mem)
        {
            List <ObjectShape> objectShapes = new List <ObjectShape>();

            foreach (ObjectShape obj in mem.getSavedObject())
            {
                ObjectShape newObj = (ObjectShape)obj.Clone();
                objectShapes.Add(newObj);
            }

            return(new MemMemento(objectShapes));
        }
        public void setMemento(MemMemento memento)
        {
            MemMemento curMem = CloneMemento(memento);

            canvasState.setObjectShapes(curMem.getSavedObject());
        }