[android-developers] How rotate a line in Android XML?

I'm trying to draw a diagonal line in an Android app with the XML, but it is not working. It simply draws a horizontal line.

main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:tools="http://schemas.android.com/tools"      android:layout_width="match_parent"      android:layout_height="match_parent"      android:paddingBottom="@dimen/activity_vertical_margin"      android:paddingLeft="@dimen/activity_horizontal_margin"      android:paddingRight="@dimen/activity_horizontal_margin"      android:paddingTop="@dimen/activity_vertical_margin"      tools:context=".TestActivity" >        <RelativeLayout      android:layout_width="match_parent"      android:layout_height="match_parent"      android:layout_alignParentLeft="true"      android:layout_alignParentTop="true"       style="@style/diagonalStyle">      </RelativeLayout>    </RelativeLayout>

styles.xml

<resources xmlns:android="http://schemas.android.com/apk/res/android">        <style name="diagonalStyle">      <item name="android:background">@drawable/background</item>      </style>    </resources>

background.xml

<?xml version="1.0" encoding="utf-8"?>  <layer-list xmlns:android="http://schemas.android.com/apk/res/android" >        <item>      <rotate          android:fromDegrees="0"          android:toDegrees="45"          android:pivotX="50%"          android:pivotY="50%" >        <shape            android:shape="line"            android:top="1dip" >            <stroke            android:width="1dip"            android:color="#FF0000" />        </shape>        </rotate>      </item>    </layer-list>