在屏幕中绘制xy轴刻度便于参考

public static void drawMark(Canvas canvas){    paint.setColor(Color.BLUE);    paint.setStyle(Paint.Style.STROKE);    paint.setAntiAlias(true);//去锯齿    paint.setTextSize(20);        // x 轴    //canvas.drawLine(0, 0, 800*3/2, 0, paint);    // x 轴刻度 每个刻度100    for(int i=0; i<14; i++){    canvas.drawLine(100*i, 0, 100*i, 15, paint);    canvas.drawText(""+i, 100*i, 20, paint);    }    // y 轴    //canvas.drawLine(5, 5, 800*3/2, 5, paint);    // y 轴刻度    for(int i=0; i<8; i++){    canvas.drawLine(0, 100*i, 15, 100*i, paint);    canvas.drawText(""+i, 5, 100*i+10, paint);    }}