CasicSmartWell / app / src / main / res / anim / popup_hide.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <alpha
        android:duration="200"
        android:fromAlpha="1.0"
        android:toAlpha="0.0" />
</set>