activity_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Menu">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Hello World, Welcome to my app"
        android:textStyle="bold"
        android:textColor="@color/colorAccent"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true"
        android:textSize="30dp"
        android:textAlignment="center"/>

</RelativeLayout>