<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="150">

    <scale
        android:fromXScale="100%"
        android:fromYScale="100%"
        android:pivotX="50%"
        android:pivotY="50%"
        android:toXScale="0"
        android:toYScale="0" />
</set>