android自己写的类似刻度尺的东西(4)

        public void run() { 
            draw(0); 
        } 
        //每次X轴移动的像素 
        private static final int MOVE = 10; 
        //游标在最左边时X轴的位置 
        private static final int INIT_POINTER_LEFT = 20; 
        //游标在最右边时X轴的位置 
        private static final int INIT_POINTER_RIGHT = 270; 
        //游标顶端Y轴的位置 
        private static final int INIT_POINTER_TOP = 36; 
        //底下刻度数字最左边的X轴位置 
        private static final int INIT_NUM_X = 18; 
        //结果的X轴位置 
        private static final int RESULT_X = 36; 
        //结果的Y轴位置 
        private static final int RESULT_Y = 25; 
        //结果的字体大小 
        private static final int RESULT_SIZE = 24; 
        //游标X轴的位置 
        private int POINTER_X = INIT_POINTER_LEFT; 
        //底下刻度数字X轴位置 
        private int NUM_X = INIT_NUM_X; 
        //底下刻度数字的Y轴位置 
        private int NUM_Y = 85; 
        //结果 
        private float result = 0; 
 
        /**
         * @param direction 方向，-1向左，1向右，0不动
         */ 
        public void draw(int direction){ 
            //获取画布 
            canvas = mSurfaceHolder.lockCanvas(); 
            if (mSurfaceHolder == null || canvas == null) {   
                return;