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

    <Button
        android:id="@+id/button_start"
        android:layout_width="30mm"
        android:layout_height="15mm"
        android:layout_weight="1"
        android:layout_centerInParent="true"
        android:text="Start" />
</RelativeLayout>
