public class MainActivity extends Activity {

       private UnityPlayer m_UnityPlayer;

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        m_UnityPlayer = new UnityPlayer(this);

        int glesMode = m_UnityPlayer.getSettings().getInt("gles_mode", 1);

        boolean trueColor8888 = false;

        m_UnityPlayer.init(glesMode, trueColor8888);

        setContentView(R.layout.activity_main);

        // Add the Unity view

        FrameLayout layout = (FrameLayout) findViewById(R.id.frameLayout2);    

        LayoutParams lp = new LayoutParams (LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);

        layout.addView(m_UnityPlayer.getView(), 0, lp);

    }

}

main.xml

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:id="@+id/frameLayout2"

    android:layout_width="match_parent"

    android:layout_height="match_parent" >

    <TextView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerHorizontal="true"

        android:layout_centerVertical="true"

        android:text="@string/hello_world"

        tools:context=".MainActivity" />

</FrameLayout>