Add text view and change background color of first fragment

NavigationComponent/app/src/main/res/layout/fragment_first.xml

@@ -1,14 +1,26 @@
 <?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http:https://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http:https://schemas.android.com/apk/res/android"
+ xmlns:app="http:https://schemas.android.com/apk/res-auto"
  xmlns:tools="http:https://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
+ android:background="@color/gray"
+ app:layout_constraintEnd_toEndOf="parent"
+ app:layout_constraintStart_toStartOf="parent"
+ app:layout_constraintTop_toTopOf="parent"
  tools:context=".FirstFragment">
 
- <!-- TODO: Update blank fragment layout -->
  <TextView
- android:layout_width="match_parent"
- android:layout_height="match_parent"
- android:text="@string/hello_blank_fragment" />
-
-</FrameLayout>
+ android:id="@+id/tv_number"
+ android:layout_width="wrap_content"
+ android:layout_height="wrap_content"
+ android:text="1"
+ android:textColor="@color/white"
+ android:textSize="100sp"
+ android:textStyle="bold"
+ app:layout_constraintBottom_toBottomOf="parent"
+ app:layout_constraintEnd_toEndOf="parent"
+ app:layout_constraintHorizontal_bias="0.5"
+ app:layout_constraintStart_toStartOf="parent"
+ app:layout_constraintTop_toTopOf="parent" />
+</androidx.constraintlayout.widget.ConstraintLayout>