android自己写的类似刻度尺的东西(12)

            dst.left = sx; 
            dst.top = sy; 
            dst.right = sx + bw; 
            dst.bottom = sy + bh; 
            canvas.drawBitmap(staff, src, dst, paint); 
        } 
         
        private float initx = 0; 
        @Override 
        public boolean onTouchEvent(MotionEvent event) { 
            switch(event.getAction()){ 
                case MotionEvent.ACTION_DOWN: 
                    initx = event.getX(); 
                    break; 
                case MotionEvent.ACTION_MOVE: 
                    float lastx = event.getX(); 
                    if(lastx > initx + 5){ 
                        isInit = false; 
                        draw(-1); 
                        initx = lastx; 
                    }else if(lastx < initx -5){ 
                        isInit = false; 
                        draw(1); 
                        initx = lastx; 
                    }