有时候需要实现类似知乎加载完成前列表中闪光的效果，这里推荐使用facebook的shimmer达到效果。 使用起来比较便利： dependencies中加入： implementation 'com.facebook.shimmer:shimmer:0.5.0'
布局中使用如下：
<com.facebook.shimmer.ShimmerFrameLayout
android:id="@+id/sfl_layout"
app:shimmer_duration="2000"
android:layout_width="270dp"
android:layout_height="40dp">
</com.facebook.shimmer.ShimmerFrameLayout>
shimmer_duration：动效周期
执行控件的startShimmer()后
运行效果如下：
下面是官方给出的属性说明：
Clip to Children
Whether to clip the shimmering effect to the children, or to opaquely draw the shimmer on top of the children. Use this if your overall layout contains transparency.
Colored
Whether you want the shimmer to affect just the alpha or draw colors on-top of the children.
Base Color
If colored is specified, the base color of the content.
Highlight Color
If colored is specified, the shimmer's highlight color.
Base Alpha
If colored is not specified, the alpha used to render the base view i.e. the unhighlighted view over which the highlight is drawn.
Highlight Alpha
If colored is not specified, the alpha of the shimmer highlight.
Auto Start
Whether to automatically start the animation when the view is shown, or not.
Duration
Time it takes for the highlight to move from one end of the layout to the other.
Repeat Count
Number of times of the current animation will repeat.
Repeat Delay
Delay after which the current animation will repeat.
Repeat Mode
What the animation should do after reaching the end, either restart from the beginning or reverse back towards it.
Direction
The travel direction of the shimmer highlight: left to right, top to bottom, right to left or bottom to top.
Dropoff
Controls the size of the fading edge of the highlight.
Intensity
Controls the brightness of the highlight at the center
Shape
Shape of the highlight mask, either with a linear or a circular gradient.
Tilt
Angle at which the highlight is tilted, measured in degrees
Fixed Width, Height
Fixed sized highlight mask, if set, overrides the relative size value
Width, Height ratio
Size of the highlight mask, relative to the layout it is applied to.
更多请参考：Shimmer for Android
如果需要在flutter中使用：shimmer | Flutter Package