Navigation architecture not using single Activity

Issue

I have implemented Navigation Architecture Framework to display couple of fragments. Unfortunately each fragment is creating a new activity. So I started the Activity with intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP) and intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP) flags but they didnt helped much as using them won't show any fragment after showing for the first time only.

nav_graph.xml

<?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"
        android:id="@+id/notification_nav_graph"
        app:startDestination="@id/openingNotificationFragment">
        <fragment
            android:id="@+id/standByScreenFragment"
            android:name="com.emaz.android.ui.notification.standby.StandByScreenFragment"
            android:label="StandByScreenFragment" />
        <fragment
            android:id="@+id/welcomeNotificationFragment"
            android:name="com.emaz.android.ui.notification.welcome.WelcomeNotificationFragment"
            android:label="WelcomeNotificationFragment" />
        <fragment
            android:id="@+id/openingNotificationFragment"
            android:name="com.emaz.android.ui.notification.ingress..OpeningNotificationFragment"
            android:label="OpeningFragment" />
        <fragment
            android:id="@+id/closingNotificationFragment"
            android:name="com.emaz.android.ui.notification.ingress..ClosingNotificationFragment"
            android:label="ClosingNotificationFragment" />
    </navigation>

HomeActivity Calling NotificationActivity as

val intent = Intent(this, NotificationActivity::class.java)
                intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
                intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP)
                startActivity(intent)

NotificationActivity And calling fragments as

notification_container.visibility = View.GONE
            fragment_layout.visibility = View.VISIBLE
            val navController = Navigation.findNavController(this, nav_host_fragment.id)

            navController.popBackStack()
            Log.e("nav", "${navController.currentDestination} and $resId < ResourceId")

            navController.navigate(resId, null)

I could see the resId changing but couldnt see on the screen. Please help.

Solution

I resolved the multiple activity creation issue. For other people who face same problem. Make sure the app is not in background if you are trying to navigate to fragment using navigation architecture.

Keeping the app active would not create new instance of the activity and app would work as expected.

Answered By - Ahmed S. Durrani