Why can't get IgnoreGravity within RelativeLayout to work?

I have two buttons. I want one to be aligned at the top center of the application. I want to get the other button to ignore the gravi开发者_如何学Goty settings and go where I tell it. How do I do this?

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/relative_layout"
    android:layout_width="fill_parent" 
    android:gravity="center_horizontal"
    android:layout_height="fill_parent" >
    <Button
        android:id="@+id/the_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Centered Button"
        android:layout_alignTop="@id/relative_layout" />

    <Button
        android:id="@+id/the_button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Random Button"
        android:ignoreGravity="@id/relative_layout" />

 </RelativeLayout>

Do not use gravity attribute of RelativeLayout, elements within RelativeLayout can be positioned with additional attributes. Try this:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/relative_layout"
android:layout_width="fill_parent" 
android:layout_height="fill_parent" >
    <Button
    android:id="@+id/the_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Centered Button"
    android:layout_centerHorizontal="true" />
    <Button
    android:id="@+id/the_button2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Random Button"/>
</RelativeLayout>

See RelativeLayout tutorial and RelativeLayout.LayoutParams docs for more information about usage of RelativeLayout.