harmony surfaceProvider绘制不显示问题要如何处理呢？

鸿蒙自定义SurfaceProvider

protectedvoidonRender(Canvascanvas,longmillisPassed){
floatoffset=millisPassed/offsetSpeed;
HiLog.info(label,"WLV_onRender"+(canvas==null)+"paint"+(paint==null));
Paintpaint1=newPaint();
paint1.setColor(Color.WHITE);
canvas.drawCircle(200,200,130,paint1);

HiLog.info(label,"WLV_onRender02");

}

有输出日志,但是看不到绘制的东西,哪位大神知道是啥原因吗