public abstract void Remove(DrawingElement d);
public abstract void Add(DrawingElement d);
public override void Remove(DrawingElement c)
{
Console.WriteLine("Cannot remove from a PrimitiveElement");
}
public override void Add(DrawingElement c)
{
Console.WriteLine("Cannot add to a PrimitiveElement");
}
public override void Remove(DrawingElement d)
{
elements.Remove(d);
}
public override void Add(DrawingElement d)
{
elements.Add(d);
}