Is it possible to set startDestination conditionally using Android Navigation Architecture Component(Android Jetpack)?

Finally, I got a solution to my query...

Put below code in onCreate() method of Activity.

Kotlin code

val navHostFragment = (supportFragmentManager.findFragmentById(R.id.home_nav_fragment) as NavHostFragment)val inflater = navHostFragment.navController.navInflaterval graph = inflater.inflate(R.navigation.nav_main)//graph.addArgument("argument", NavArgument)graph.startDestination = R.id.fragment1//or//graph.startDestination = R.id.fragment2navHostFragment.navController.graph = graph

Java code

NavHostFragment navHostFragment = (NavHostFragment) getSupportFragmentManager().findFragmentById(R.id.home_nav_fragment);  // HostfragmentNavInflater inflater = navHostFragment.getNavController().getNavInflater();NavGraph graph = inflater.inflate(R.navigation.nav_main);//graph.addArgument("argument", NavArgument)graph.setStartDestination(R.id.fragment1);navHostFragment.getNavController().setGraph(graph);navHostFragment.getNavController().getGraph().setDefaultArguments(getIntent().getExtras());NavigationView navigationView = findViewById(R.id.navigationView);NavigationUI.setupWithNavController(navigationView, navHostFragment.getNavController());

Additional Info

As @artnest suggested, remove the app:navGraph attribute from the layout. It would look something like this after removal

<?xml version="1.0" encoding="utf-8"?><FrameLayout 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">    <androidx.fragment.app.FragmentContainerView        android:id="@+id/home_nav_fragment"        android:name="androidx.navigation.fragment.NavHostFragment"        android:layout_width="match_parent"        android:layout_height="match_parent"        app:defaultNavHost="true" /></FrameLayout>

In the case of a fragment tag used instead of FragmentContainerView, the above changes remain the same

Some of the APIs have changed, are unavailable or are not necessary since Akash's answer. It's a bit simpler now.

MainActivity.java:

@Overrideprotected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);  NavHostFragment navHost = (NavHostFragment) getSupportFragmentManager().findFragmentById(R.id.fragment_main_nav_host);  NavController navController = navHost.getNavController();  NavInflater navInflater = navController.getNavInflater();  NavGraph graph = navInflater.inflate(R.navigation.navigation_main);  if (false) {    graph.setStartDestination(R.id.oneFragment);  } else {    graph.setStartDestination(R.id.twoFragment);  }  navController.setGraph(graph);}

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?><androidx.constraintlayout.widget.ConstraintLayout   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=".MainActivity">  <!-- Following line omitted inside <fragment> -->  <!-- app:navGraph="@navigation/navigation_main" -->  <fragment    android:id="@+id/fragment_main_nav_host"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:name="androidx.navigation.fragment.NavHostFragment"  /></androidx.constraintlayout.widget.ConstraintLayout>

navigation_main.xml:

<?xml version="1.0" encoding="utf-8"?><!-- Following line omitted inside <navigation>--><!-- app:startDestination="@id/oneFragment" --><navigation 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/navigation_main"  >  <fragment    android:id="@+id/oneFragment"    android:name="com.apponymous.apponymous.OneFragment"    android:label="fragment_one"    tools:layout="@layout/fragment_one"/>  <fragment    android:id="@+id/twoFragment"    android:name="com.apponymous.apponymous.TwoFragment"    android:label="fragment_two"    tools:layout="@layout/fragment_two"/></navigation>

This can be done with navigation action. Because fragmentA is your start destination, so define an action in fragmentA.

Note these two fields: app:popUpToInclusive="true" app:popUpTo="@id/fragmentA"

<navigation 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/lrf_navigation"   app:startDestination="@id/fragmentA">   <fragment       android:id="@+id/fragmentA"       android:name="com.mindinventory.FragmentA"       android:label="fragment_a"       tools:layout="@layout/fragment_a">    <action android:id="@+id/action_a_to_b"            app:destination="@id/fragmentB"            app:popUpToInclusive="true"            app:popUpTo="@id/fragmentA"/>   <fragment>   <fragment       android:id="@+id/fragmentB"       android:name="com.mindinventory.FragmentB"       android:label="fragment_b"       tools:layout="@layout/fragment_b"/></navigation>

When your MainActivity started, just do the navigation with action id, it will remove fragmentA in the stack, and jump to fragmentB. Seemingly, fragmentB is your start destination.

if(!isAllSetUp){  // FragmentB  navController.navigate(R.id.action_a_to_b)}