Android 4.0: canvas.setViewport error

I'm getting an error in my code. the method setViewPort(int, int) cannot be defined for the type canvas.

I am trying to implement multi touch functionality on an ImageView, the intire class is far too long to put up here but if you require more information just comment.

@Override

        protected void onDraw(Canvas canvas) {

            if(layout) {

                if(!viewSet) {

//line that's causing issue                 

canvas.setViewport(displayWidth, displayHeight);

                    viewSet = true;

                }

can't figure out what the issue is, have all necessary imports etc.

Would it be the fact I'm using Android 4.0?

thanks.

Shaw