Android : Expand Animation to work on both sides (on negative axis)

I implemented an ExpandAnimation on view like this:

        @Override
    protected void applyTransformation(float interpolatedTime,
                                       Transformation t) {
        LayoutParams lp =
                (LayoutParams) view.getLayoutParams();
        if(rightAnimation){
            lp.width = (int) (mStartWidth + mDeltaWidth *
                    interpolatedTime);
            view.setLayoutParams(lp);
        }else{

        }

    }

With this animation my view expands and shrinks.

What i want to do is to implement this animation to the other side as well. But i get confused a little bit, since shrinking the width will not work. (Since minus widths or heights are not allowed)

Does anyone know a better way to implement expand animation to the left or up side as well?