Android 5.0 introduced the concept of Z axis, so it has this style, which is currently the more popular Material Design.
1. android:elevation Sets the height of the component "floating", but setting this attribute can make the component present a 3D effect.
2. android:translationZ Sets the displacement of the component in the Z direction (vertical screen direction).
By default, the shadow is provided by the background, if the control does not set the background, you need to add
android:outlineProvider="bounds"