Navigation destination is unknown to this NavController?

Question

I am using the navigation graph in my project. My activity has toolbar and navhostfragment

<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=".view.MainActivity">

<androidx.appcompat.widget.Toolbar
    android:id="@+id/my_toolbar"
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize"
    android:background="@color/colorPrimary"
    android:elevation="4dp"
    android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
    app:title="">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <androidx.appcompat.widget.AppCompatTextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:drawableLeft="@mipmap/ic_launcher_new_round"
            android:gravity="center"
            android:text="@string/app_name"
            android:textColor="@android:color/white"
            android:textSize="20sp"
            android:textStyle="bold"
            android:visibility="gone" />

        <androidx.appcompat.widget.AppCompatImageButton
            android:id="@+id/directory"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_marginRight="8dp"
            android:layout_toLeftOf="@+id/settings"
            android:background="@android:color/transparent"
            android:src="@drawable/directory"
            android:tint="@android:color/white"
            android:visibility="gone" />

        <androidx.appcompat.widget.AppCompatImageButton
            android:id="@+id/settings"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_marginRight="8dp"
            android:layout_toLeftOf="@+id/logout"
            android:background="@android:color/transparent"
            android:src="@drawable/settings"
            android:tint="@android:color/white" />

        <androidx.appcompat.widget.AppCompatImageButton
            android:id="@+id/logout"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_centerVertical="true"
            android:layout_marginRight="8dp"
            android:background="@android:color/transparent"
            android:src="@drawable/logout"
            android:tint="@android:color/white" />


    </RelativeLayout>
</androidx.appcompat.widget.Toolbar>

<fragment
    android:id="@+id/navigationHostFragment"
    android:name="androidx.navigation.fragment.NavHostFragment"
    android:layout_width="0dp"
    android:layout_height="0dp"
    app:defaultNavHost="true"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/my_toolbar"
    app:navGraph="@navigation/main" />
 </androidx.constraintlayout.widget.ConstraintLayout>

In the toolbar I have 2 buttons settings and logout. When I am at the home fragment the settings click work fine but when I am on any other fragment , clicking the settings gives me exception.

My navigation graph is as follows

<?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/main"
app:startDestination="@id/homeFragment">

<fragment
    android:id="@+id/homeFragment"
    android:name="com.mountmeru.view.HomeFragment"
    android:label="fragment_home"
    tools:layout="@layout/fragment_home" >
    <action
        android:id="@+id/action_homeFragment_to_notificationFragment"
        app:destination="@id/notificationFragment" />
    <action
        android:id="@+id/action_homeFragment_to_categoryFragment"
        app:destination="@id/categoryFragment" />

    <action
        android:id="@+id/action_homeFragment_to_settingsFragment"
        app:destination="@id/settingsFragment" />
</fragment>
<fragment
    android:id="@+id/settingsFragment"
    android:name="com.mountmeru.view.settings.SettingsFragment"
    android:label="fragment_settings"
    tools:layout="@layout/fragment_settings" >
    <action
        android:id="@+id/action_settingsFragment_to_profileFragment"
        app:destination="@id/profileFragment" />
    <action
        android:id="@+id/action_settingsFragment_to_resetPasswordFragment"
        app:destination="@id/resetPasswordFragment" />
</fragment>

On click code in activity for settings

  navigationController.navigate(
            R.id.action_homeFragment_to_settingsFragment)

I get the exception when I click from notificationFragment

 java.lang.IllegalArgumentException: navigation destination com.mountmeru:id/action_homeFragment_to_settingsFragment is unknown to this NavController

Answer 1

You declare an action just for navigating from HomeFragment to SettingsFragment. This action can only be used with HomeFragment as a starting point, so for other Fragments you get the Exception "{actionId} is unknown to this NavController".

Since you need to navigate to SettingsFragment from several starting points, you can declare a global action

<action android:id="@+id/action_global_settingsFragment"
      app:destination="@id/settingsFragment"/>