<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <AnalogClock
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <DigitalClock
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center" />

</LinearLayout>