FunFacts Background color won't change to RED. "Dynamically Changing the Background Color" video

private FactBook mFactBook = new FactBook();

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_fun_facts);

    // Declare our View variables and assign the the Views from the layout file
    final TextView factLabel = (TextView) findViewById(R.id.factTextView);
    Button showFactButton = (Button) findViewById(R.id.showFactButton);
    final RelativeLayout relativeLayout = (RelativeLayout) findViewById(R.id.relativeLayout);

    View.OnClickListener listener = new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            String fact = mFactBook.getFact();
            // Update the label with our dynamic fact
            factLabel.setText(fact);
            relativeLayout.setBackgroundColor(Color.RED);

            //Demonstrate how to call the object and replace a value inside the array
          //mFactBook.mFacts[0] = "Pigs are cool";
        }
    };
    showFactButton.setOnClickListener(listener);
}

<TextView
    android:text="Did you know?"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="24sp"
    android:textColor="#80ffffff" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Ants stretch when they wake up in the morning."
    android:id="@+id/factTextView"
    android:layout_centerVertical="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:textSize="24sp"
    android:textColor="@android:color/white" />

<Button
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Show Another Fun Fact"
    android:id="@+id/showFactButton"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:background="@android:color/white" />

//Member variables
public String[] mFacts = {
        "Ants stretch when they wake up in the morning.",
        "Ostriches can run faster than horses.",
        "Olympic gold medals are actually made mostly of silver.",
        "You are born with 300 bones; by the time you are an adult you will have 206.",
        "It takes about 8 minutes for light from the Sun to reach Earth.",
        "Some bamboo plants can grow almost a meter in just one day.",
        "The state of Florida is bigger than England.",
        "Some penguins can leap 2-3 meters out of the water.",
        "On average, it takes 66 days to form a new habit.",
        "Mammoths still walked the earth when the Great Pyramid was being built." };

//Method (abilities: things the object can do)
public String getFact() {

    String fact = "";

    // Randomly select a fact
    Random randomGenerator = new Random();  // Construct a new Random number generator
    int randomNumber = randomGenerator.nextInt(mFacts.length);

    fact = mFacts[randomNumber];

    return fact;
}