Action is unknown to this NavController

Question

I'm providing data transfer between fragments in two different ways, first is working normal, while a safe data type cause run-time crash. I'm using that Android docs: https://developer.android.com/topic/libraries/architecture/navigation/navigation-implementing#Safe-args

Don't understand how could I resolve the problem. Thanks for your help

07-13 11:40:07.986 8119-8119/com.flexdecision.ak_lex.navigationsimple E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.flexdecision.ak_lex.navigationsimple, PID: 8119
java.lang.IllegalArgumentException: navigation destination com.flexdecision.ak_lex.navigationsimple:id/transferAction is unknown to this NavController
    at androidx.navigation.NavController.navigate(NavController.java:669)
    at androidx.navigation.NavController.navigate(NavController.java:628)
    at androidx.navigation.NavController.navigate(NavController.java:690)
    at com.flexdecision.ak_lex.navigationsimple.InitialFragment.makeTransfer(InitialFragment.java:58)
    at com.flexdecision.ak_lex.navigationsimple.InitialFragment.lambda$onViewCreated$0(InitialFragment.java:47)
    at com.flexdecision.ak_lex.navigationsimple.-$$Lambda$InitialFragment$shEoLbIe0sVhbTcJ2Al_FvBuU7g.onClick(lambda)
    at android.view.View.performClick(View.java:5198)
    at android.view.View$PerformClick.run(View.java:21147)
    at android.os.Handler.handleCallback(Handler.java:739)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:148)
    at android.app.ActivityThread.main(ActivityThread.java:5417)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

Navigation graph:

<?xml version="1.0" encoding="utf-8"?>
<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/nav_graph"
    app:startDestination="@id/initialFragment">

    <fragment
        android:id="@+id/initialFragment"
        android:name="com.flexdecision.ak_lex.navigationsimple.InitialFragment"
        android:label="fragment_initial"
        tools:layout="@layout/fragment_initial">
        <action
            android:id="@+id/transferAction"
            app:destination="@+id/nextFragment" />
    </fragment>
    <fragment
        android:id="@+id/nextFragment"
        android:name="com.flexdecision.ak_lex.navigationsimple.NextFragment"
        android:label="fragment_next"
        tools:layout="@layout/fragment_next" >
        <argument
            android:name="firstName"
            android:defaultValue="none"
            app:type="string" />
        <argument
            android:name="lastName"
            android:defaultValue="none"
            app:type="string" />
    </fragment>
</navigation>

Activity layout:

<android.support.constraint.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">

    <fragment
        android:id="@+id/nav_host_fragment"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:defaultNavHost="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:navGraph="@navigation/nav_graph" />
</android.support.constraint.ConstraintLayout>

Sender:

import androidx.navigation.Navigation;

public class InitialFragment extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_initial, container, false);
    }

    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        Button transactionBtn = view.findViewById(R.id.transaction);
        transactionBtn.setOnClickListener(v -> makeTransfer(v));
    }

    private void makeTransfer(View view) {
        Bundle bundle = new Bundle();
        bundle.putString("name", "Aleksey");
        Navigation.findNavController(view).navigate(R.id.transferAction, bundle);

        //Type safe passing data
        InitialFragmentDirections.TransferAction action = InitialFragmentDirections.transferAction();
        action.setLastName("Petrov");
        Navigation.findNavController(view).navigate(action);
    }
}

Receiver:

public class NextFragment extends Fragment {
    private static final String ARG_PARAM1 = "name";

    private String mParam1;
    private TextView firstName;

    public NextFragment() {
        // Required empty public constructor
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            mParam1 = getArguments().getString(ARG_PARAM1);
            Log.d("Next", "Param: " + mParam1);
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_next, container, false);
    }


    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        firstName = view.findViewById(R.id.firstName);
        TextView lastName = view.findViewById(R.id.lastNameTV);
        firstName.setText(mParam1);

        String ln = NextFragmentArgs.fromBundle(getArguments()).getLastName();
        lastName.setText(ln);
    }
}

additional:

apply plugin: "androidx.navigation.safeargs"

dependencies {
    def nav_version = "1.0.0-alpha03"

    implementation "android.arch.navigation:navigation-fragment:$nav_version"
    implementation "android.arch.navigation:navigation-ui:$nav_version"
}

What is the purpose of the 'Run code snippet' button above? – IgorGanapolsky Dec 27 '19 at 19:15 — IgorGanapolsky, Dec 27 '19 at 19:15

score 29 · Accepted Answer · answered Jul 13 '18 at 16:16

You calling twice to 'Navigation.findNavController(view).navigate':

private void makeTransfer(View view) {
    Bundle bundle = new Bundle();
    bundle.putString("name", "Aleksey");
    Navigation.findNavController(view).navigate(R.id.transferAction, bundle);

    //Type safe passing data 
    InitialFragmentDirections.TransferAction action = InitialFragmentDirections.transferAction();
    action.setLastName("Petrov");
    Navigation.findNavController(view).navigate(action);
}

First time with bundle and second time with safe args, but after the first call your destination already changed to 'nextFragment', and when you call second 'navigate' the 'NavController' looking for 'transferAction' action inside 'nextFragment' and throws exception.

heyheyhey · Answer 2 · 2020-10-29T11:13:44.150

5

In my case, I was trying to navigate from fragment A to fragment B, but fragment A was not navigated to via the nav controller (aka, not present in the navigation graph), it was a fragment that I explicitly initialized initialized from a FragmentStateAdater (tied to a ViewPager). The solution was to create a global action to fragment B, instead of one from fragment A to fragment B

edited Oct 29 '20 at 11:13

answered Jun 25 '20 at 06:25

heyheyhey

1,216
8
12

" ...but fragment A was not navigated to via the nav controller, it was a fragment that I explicitly initialized.." That was the part of the statement that gave me clue to my issue and i got it solved using viewholder class. – Ahmad A.A Oct 27 '20 at 19:47
Thank you for this answer, Its so funny that I have been battling with this navigation issue for like a year now & instead of understanding the problem like you posted, I usually find a workaround. Now I know the exact cause & the issue is solved going forward. – truthsayer May 12 '22 at 08:58

score -5 · Answer 3 · answered Jan 28 '20 at 09:26

1.Add bellow Dependencies In gradle File

def nav_version = "2.2.0"
implementation "androidx.navigation:navigation-fragment:$nav_version"
implementation "androidx.navigation:navigation-ui:$nav_version"

2.Add Below Plugin in Your Project/Top Level Gradle

    def nav_version = "2.2.0"
    classpath "androidx.navigation:navigation-safe-args-gradle-plugin:$nav_version"

3.Rebuild Your project

Action is unknown to this NavController

3 Answers3