Add fragment container view to activity_main.xml and choose my_nav as…

… navigation graph

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

@@ -6,13 +6,19 @@
  android:layout_height="match_parent"
  tools:context=".MainActivity">
 
- <TextView
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:text="Hello World!"
+ <androidx.fragment.app.FragmentContainerView
+ android:id="@+id/fragmentContainerView"
+ android:name="androidx.navigation.fragment.NavHostFragment"
+ android:layout_width="match_parent"
+ android:layout_height="match_parent"
+ android:layout_marginStart="1dp"
+ android:layout_marginTop="1dp"
+ android:layout_marginEnd="1dp"
+ android:layout_marginBottom="1dp"
+ app:defaultNavHost="true"
  app:layout_constraintBottom_toBottomOf="parent"
- app:layout_constraintLeft_toLeftOf="parent"
- app:layout_constraintRight_toRightOf="parent"
- app:layout_constraintTop_toTopOf="parent" />
-
+ app:layout_constraintEnd_toEndOf="parent"
+ app:layout_constraintStart_toStartOf="parent"
+ app:layout_constraintTop_toTopOf="parent"
+ app:navGraph="@navigation/my_nav" />
 </androidx.constraintlayout.widget.ConstraintLayout>