Android Basics: User Interface

HappyBirthday

<?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:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.android.happybirthday.MainActivity">

    <ImageView
        android:src="@drawable/androidparty"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:scaleType="centerCrop"
        android:id="@+id/imageView" />
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Happy Birthday, Ivona!"
        android:fontFamily="sans-serif-light"
        android:textSize="36sp"
        android:textColor="#FFF"
        android:paddingLeft="@dimen/activity_horizontal_margin"
        android:paddingTop="@dimen/activity_vertical_margin"/>
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:text="From Damir"
        android:fontFamily="sans-serif-light"
        android:textSize="36sp"
        android:textColor="#FFF"
        android:paddingRight="@dimen/activity_horizontal_margin"
        android:paddingBottom="@dimen/activity_vertical_margin"/>
</RelativeLayout>