I had a similar way of redirecting to different fragment based on a condition. But scenario was different.
I had to redirect to different fragments based on type of user logged in and status of the registration. With child navigation's the same would be possible.
For that I had to send the data/condition to landing fragment. Based on this data redirection could be possible.
Similar approach may be tried for your scenario as well.
NOTE: Although the below did not included Firebase and corresponding
dependencies.
<!-- Parent Graph -->
<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/landingFragment">
<!-- Landing Child Graph -->
<navigation
android:id="@+id/landingFragment"
app:startDestination="@id/dashboardFragment">
<fragment
android:id="@+id/dashboardFragment"
android:name="com.....DashboardFrag"
tools:layout="@layout/fg_dashboard">
<argument
android:name="CONTINUE_REGISTRATION"
android:defaultValue="false"
app:argType="boolean" />
<action
android:id="@+id/continueRegistration"
app:destination="@id/registration_graph" />
</fragment>
</navigation>
<!-- Child Graph -->
<navigation
android:id="@+id/registration_graph"
app:startDestination="@id/opRegFragment">
<fragment
android:id="@+id/opRegFragment"
android:name="com.....RegFieldsFragment"
tools:layout="@layout/fg_registration">
</fragment>
</navigation>
</navigation>
Now in the Dashboard Fragment do like below.
class DashboardFrag : BaseFrag {
private var continueReg: Boolean = false
override fun onCreate(savedInstanceState: Bundle?) {
DashboardFragArgs.fromBundle(requireArguments()).apply {
continueReg = CONTINUEREGISTRATION
}
super.onCreate(savedInstanceState)
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
if (continueReg) {
registrationContinueAction()
}
}
private fun registrationContinueAction() {
val action = DashboardFragDirections.continueRegistration()
findNavController().navigate(action)
}
}
EDIT 1:
As per your comment, you can move the opening new fragment as part of separate graph as well. With below that should work.
Main nav_graph.xml
<!-- Parent Graph -->
<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/landingFragment">
<!-- Landing Child Graph -->
<navigation
android:id="@+id/landingFragment"
app:startDestination="@id/dashboardFragment">
<fragment
android:id="@+id/dashboardFragment"
android:name="com.....DashboardFrag"
tools:layout="@layout/fg_dashboard">
<argument
android:name="CONTINUE_REGISTRATION"
android:defaultValue="false"
app:argType="boolean" />
<action
android:id="@+id/continueRegistration"
app:destination="@id/registration_graph" />
</fragment>
</navigation>
</navigation>
Now in new graph (sub_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"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/sub_nav_graph"
app:startDestination="@id/SubGraphLangingFg">
<fragment android:id="@+id/SubGraphLangingFg"
android:name="com....SubGraphFirstFg"
android:label="fragment_landingsub_fg"
tools:layout="@layout/fragment_landingsub_fg">
</fragment>
</navigation>
And now , it is better to have a new Activity to handle all the sub fragments under this flow. Again it depends on the requirement and feasibility.
in Manifest.xml , register the new Activity
<activity android:name="com.....ChildGraphLandingActivity" />
And the new Activity would be:
class ChildGraphLandingActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_subgraph)
}
}
activity_subgraph.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.....ChildGraphLandingActivity">
<fragment
android:id="@+id/fragment_container"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="@navigation/sub_nav_graph" />
</FrameLayout>
Now in the invoking fragment, below should be done.
class DashboardFrag : BaseFrag {
......
private fun registrationContinueAction() {
//If you are expecting a call back
startActivityForResult(Intent(context, ChildGraphLandingActivity::class.java)....)
//If call back is not expected
startActivity(Intent(context, ChildGraphLandingActivity::class.java))
}
}
