Android: How to dynamically include a XML Layout?

I want to decompose my UI into several XML Layouts. The first one would be the main layout, and the other ones would be the content layouts.

I would like to be able to set which content_layout should be included dynamically at run-time, so I don't want to set a "layout="@+layout/content_layout" in my XML file.

Here are my layouts:

main_layout.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="600dp"
    android:layout_height="800dp" >

    <TextView
        android:id="@+id/title"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true" />

    <include /> <!-- I WANT TO INCLUDE MY CONTENT HERE -->

    <Button
        android:id="@+id/cancelButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:text="Cancel" />

</RelativeLayout>

content_layout.xml:

<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/whatever"
    android:layout_height="wrap_content"
    android:layout_width="fill_parent" />

content_layout2.xml:

<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/whatever2"
    android:layout_height="wrap_content"
    android:layout_width="fill_parent" />

How can I do that?

Thanks!