ScreenFilter/res/layout/preferences.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/ReenableButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginBottom="8.0dip"
        android:layout_marginTop="4.0dip"
        android:text="@string/reenable_button"
        android:textSize="18.0dip" />

    <me.yoqi.screenfilter.BrightnessSelector
        android:id="@+id/PreferencesBrightnessSelector"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

</LinearLayout>