Navegar por una aplicación Jetpack de varios módulos sin magia ni DI

Cuando comienzas a crear una aplicación en la que hay al menos varias pantallas, siempre surge la pregunta: cuál es la mejor manera de implementar la navegación. La pregunta se vuelve más interesante y difícil cuando se va a realizar una aplicación de varios módulos. Hace aproximadamente un año y medio, hablé sobre cómo se puede implementar la navegación usando Jetpack en un proyecto de varios módulos. Y ahora, después de un tiempo, me topé con mi implementación y me di cuenta de que es posible volar a través de los módulos en el mismo Jetpack más fácilmente: sin magia ni DI.

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Arquitectura del proyecto

:

Android : feature- c shared- . app , feature shared.

Single Activity, Activity ,

shared:navigation . .

fun Fragment.navigate(actionId: Int, hostId: Int? = null, data: Serializable? = null) {
	val navController = if (hostId == null) {
		findNavController()
	} else {
		Navigation.findNavController(requireActivity(), hostId)
	}

	val bundle = Bundle().apply { putSerializable("navigation data", data) }

	navController.navigate(actionId, bundle)
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

:

• actionId - id

  
  
  
  
  

• hostId - id . ,

  
  
  
  
  

• data - Serializable

  
  
  
  
  

, .

val Fragment.navigationData: Serializable?
	get() = arguments?.getSerializable("navigation data")
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

id , feature . res/value/ids.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
	<item name="host_global" type="id"/>
	<item name="host_main" type="id"/>
</resources>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

! , .

feature-

splash. , , . : splash .

id : res/value/ids.xml splash

<?xml version="1.0" encoding="utf-8"?>
<resources>
	<item name="action_splashFragment_to_mainFragment" type="id"/>
	<item name="action_splashFragment_to_onboardingFragment" type="id"/>
</resources>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Id , , shared:navigation. .

id .

import com.example.smmn.shared.navigation.navigate

class SplashFragment : Fragment(R.layout.fragment_splash) {

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        buttonToOnboarding.setOnClickListener {
            navigate(R.id.action_splashFragment_to_onboardingFragment)
        }

        buttonToMain.setOnClickListener {
            navigate(R.id.action_splashFragment_to_mainFragment)
        }
    }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, shared:navigation.

.

Activity. . Activity.

class MainActivity : AppCompatActivity(R.layout.activity_main)
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.fragment.app.FragmentContainerView 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/host_global"
    android:name="androidx.navigation.fragment.NavHostFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:defaultNavHost="true"
    app:navGraph="@navigation/navigation_global"
    tools:ignore="FragmentTagUsage" />
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, . app res/navigation/navigation_global.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/navigation_global"
    app:startDestination="@id/splashFragment">

    <fragment
        android:id="@+id/splashFragment"
        android:name="com.example.smmn.feature.splash.SplashFragment"
        android:label="SplashFragment">
        <action
            android:id="@id/action_splashFragment_to_mainFragment"
            app:destination="@id/mainFragment"
            app:popUpTo="@id/navigation_global" />
        <action
            android:id="@id/action_splashFragment_to_onboardingFragment"
            app:destination="@id/onboardingFragment"
            app:popUpTo="@id/navigation_global" />
    </fragment>
    <fragment
        android:id="@+id/mainFragment"
        android:name="com.example.smmn.feature.main.MainFragment"
        android:label="MainFragment" >
        <action
            android:id="@id/action_mainFragment_to_splashFragment"
            app:popUpTo="@id/navigation_global"
            app:destination="@id/splashFragment" />
    </fragment>
    <fragment
        android:id="@+id/onboardingFragment"
        android:name="com.example.smmn.feature.onboarding.OnboardingFragment"
        android:label="OnboardingFragment">
        <action
            android:id="@id/action_onboardingFragment_to_mainFragment"
            app:destination="@id/mainFragment"
            app:popUpTo="@id/navigation_global" />
    </fragment>
</navigation>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, action () . , , "Back".

, id +, id , id, feature .

id splash

<item name="action_splashFragment_to_mainFragment" type="id"/>
<item name="action_splashFragment_to_onboardingFragment" type="id"/>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

        <action
            android:id="@id/action_splashFragment_to_mainFragment"
            app:destination="@id/mainFragment"
            app:popUpTo="@id/navigation_global" />
        <action
            android:id="@id/action_splashFragment_to_onboardingFragment"
            app:destination="@id/onboardingFragment"
            app:popUpTo="@id/navigation_global" />
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Jetpack . , BottomNavigation .

.

navigation-ui, .

main BottomNavigation res/menu/menu_main.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/profileFragment"
        android:icon="@drawable/ic_baseline_account_circle_24"
        android:title="@string/main_menu_title_profile" />
    <item
        android:id="@+id/settingsFragment"
        android:icon="@drawable/ic_baseline_settings_24"
        android:title="@string/main_menu_title_settings" />
</menu>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

res/navigation/navigation_main.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/navigation_main"
    app:startDestination="@id/profileFragment">

    <fragment
        android:id="@+id/profileFragment"
        android:name="com.example.smmn.feature.profile.ProfileFragment"
        android:label="ProfileFragment">
        <action
            android:id="@id/action_profileFragment_to_infoFragment"
            app:destination="@id/infoFragment" />
    </fragment>
    <fragment
        android:id="@+id/settingsFragment"
        android:name="com.example.smmn.feature.settings.SettingsFragment"
        android:label="SettingsFragment" />
    <fragment
        android:id="@+id/infoFragment"
        android:name="com.example.smmn.feature.info.InfoFragment"
        android:label="InfoFragment" />
</navigation>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

id res/menu/menu_main.xml. , id .

res/layout/fragment_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"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <fragment
        android:id="@id/host_main"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:defaultNavHost="true"
        app:layout_constraintBottom_toTopOf="@+id/bottomNavigationView"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:navGraph="@navigation/navigation_main" />

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/bottomNavigationView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@android:color/white"
        app:elevation="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:menu="@menu/menu_main" />
</androidx.constraintlayout.widget.ConstraintLayout>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

bottomNavigationView

class MainFragment : Fragment(R.layout.fragment_main) {

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        NavigationUI.setupWithNavController(
            bottomNavigationView,
            Navigation.findNavController(requireActivity(), R.id.host_main)
        )
    }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, , , . , c : .

, ( , ) , . , .

, id . , shared:navigation.

class SettingsFragment : Fragment(R.layout.fragment_settings) {

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        buttonToSplash.setOnClickListener {
            navigate(R.id.action_mainFragment_to_splashFragment, R.id.host_global)
        }
    }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

Id res/values/ids.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
	<item name="action_mainFragment_to_splashFragment" type="id"/>
</resources>
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, bundle. - Serializable .

, Serializable . .

Serializable , , , , . shared:model Serializable Info.

data class Info(
    val name: String,
    val surname: String
) : Serializable
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

profile info. Info .

class ProfileFragment : Fragment(R.layout.fragment_profile) {

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        buttonToInfo.setOnClickListener {
            navigate(R.id.action_profileFragment_to_infoFragment, data = Info("name", "surname"))
        }
    }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, .

class InfoFragment : Fragment(R.layout.fragment_info) {

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        val info = navigationData as? Info ?: return
        textView.text = info.toString()
    }
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, , .

, Jetpack . , , .

.

!