How can I create and position a container over a Layout?

Here is my Layout XML code:

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

    <FrameLayout
        android:id="@+id/mapWithOverlay"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />
</LinearLayout>

How can I create a container that has a TextView and a Button and then position this container where I want on top of the FrameLayout?

Thanks in advance