特殊纪念日专用灰色代码

//设置整个APP的所有活动页面变为黑白色；屏蔽掉色彩，特殊节日需要用到；
` private void initGrayScreen(){
Paint paint = new Paint();
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);
paint.setColorFilter(new ColorMatrixColorFilter(cm));
getWindow().getDecorView().setLayerType(View.LAYER_TYPE_HARDWARE, paint);
}
`
```
html {
height: 100%;
FILTER: gray;
-webkit-filter: grayscale(100%);
}

```