public ShapeModel()
{
_shapeList = new ShapeList();
_currentState = new PointerState(this);
_commandManager = new CommandManager();
}
//更換State
private void ChangeState()
{
if (_shapeType == DrawingType.Pointer)
{
_state = new PointerState(this);
}
else
{
_state = new DrawingState(this);
}
NotifyObserver();
}