I am trying fragment transaction using navigation host fragment, but on navigating to the destination fragment the old fragment is still visible on screen like fragment added on one another.
Here is my code:
some_nav.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/some_nav"
app:startDestination="#+id/WelcomeFragment">
<fragment
android:id="#+id/WelcomeFragment"
android:name="com.example.ui.fragment.WelcomeFragment"
android:label="WelcomeFragment">
<action
android:id="#+id/action_WelcomeFragment_to_secondFragment"
app:destination="#+id/secondFragment"
/>
</fragment>
<fragment
android:id="#+id/secondFragment"
android:name="com.example.ui.fragment.SomeFragment"
android:label="secondFragment">
</fragment>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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=".ui.MainActivity">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="#dimen/action_bar_height"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay"
app:theme="#style/AppTheme.AppBarOverlay" />
<TextView
android:id="#+id/title_text"
android:layout_width="match_parent"
android:layout_height="#dimen/action_bar_height" />
<fragment
android:id="#+id/all_navigation_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
app:navGraph="#navigation/some_nav"
app:defaultNavHost="true"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/toolbar"
android:layout_gravity="top"
tools:ignore="MergeRootFrame" />
</RelativeLayout>
WelcomeFragment.kt
button.setOnClickListener{
findNavController().navigate(R.id.action_WelcomeFragment_to_secondFragment)
}
MainActivity.kt
override fun onCreate(savedInstanceState: Bundle?) {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_FOLLOW_SYSTEM)
super.onCreate(savedInstanceState)
Log.d(TAG, "OnCreate")
setContentView(R.layout.activity_main)
host = supportFragmentManager
.findFragmentById(R.id.all_navigation_host_fragment) as NavHostFragment? ?: return
navController = host.navController
navController.addOnDestinationChangedListener { _, destination, _ ->
val dest: String = try {
resources.getResourceName(destination.id)
} catch (e: Resources.NotFoundException) {
Integer.toString(destination.id)
}
Log.d(TAG, "Navigated to $dest")
var toolBarText = R.string.title
when (destination.id) {
R.id.WelcomeFragment -> toolBarText = R.string.title
R.id.secondFragment -> toolBarText = R.string.button
}
setupToolbar(toolBarText)
}
}
Why is it overwriting on one another ? did i miss anything obvious?
Related
I'm trying to make an memo app, and this is my first time with application programming.
When I tried to run the code on my device it just dies after showing the IntroActivity and the error log says: "You must call setGraph() before calling getGraph()"
Below is the code.
class ListActivity : AppCompatActivity() {
private lateinit var appBarConfiguration: AppBarConfiguration
private lateinit var binding: ActivityListBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityListBinding.inflate(layoutInflater)
setContentView(binding.root)
setSupportActionBar(binding.toolbar)
val navController = findNavController(R.id.nav_host_fragment_content_list)
appBarConfiguration = AppBarConfiguration(navController.graph)
setupActionBarWithNavController(navController, appBarConfiguration)
binding.fab.setOnClickListener { view ->
val intent=Intent(applicationContext, DetailActivity::class.java)
startActivity(intent)
}
}
override fun onSupportNavigateUp(): Boolean {
val navController = findNavController(R.id.nav_host_fragment_content_list)
return navController.navigateUp(appBarConfiguration)
|| super.onSupportNavigateUp()
}
}
When I googled about this error there were only answers about androidx.navigation version 2.3.0-alpha2, so I checked my build.gradle.
I was using 2.5.0, the latest version.
How else can I solve this problem?
activity_list.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout 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=".ListActivity">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/Theme.DimoMemo.AppBarOverlay">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/Theme.DimoMemo.PopupOverlay" />
</com.google.android.material.appbar.AppBarLayout>
<include layout="#layout/content_list" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_marginEnd="#dimen/fab_margin"
android:layout_marginBottom="16dp"
app:srcCompat="#drawable/ic_add"
android:layout_marginRight="#dimen/fab_margin" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
content_list.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/contentLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<fragment
android:id="#+id/nav_host_fragment_content_list"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp" />
</FrameLayout>
check if the layout contains:
app:navGraph="#navigation/nav_graph"
app:defaultNavHost="true"
your nav_host_fragment_content_list must look like:
<fragment
android:id="#+id/nav_host_fragment_content_list"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:navGraph="#navigation/your_nav_graph"
app:defaultNavHost="true" />
https://developer.android.com/guide/navigation/navigation-getting-started
I updated the navigation library from 2.3.5 to 2.4.2. After update I started getting this error: java.lang.IllegalArgumentException: No destination with ID XXX is on the NavController's back stack. The current destination is null. The error occurs after the following steps: FirstFragment -> SecondFragment [with another BottomNavigationView] -> ThirdFragment -> SecondFragment [crash]
I'll try to describe what I'm doing:
I have two fragments with BottomNavigationView.
First Fragment
class MainBottomNavFragment : Fragment() {
private lateinit var navController: NavController
override fun onStart() {
super.onStart()
if (!::navController.isInitialized) {
navController =
Navigation.findNavController(requireActivity(), R.id.mainBottomNavHostFragment)
}
binding.bottomNavigation.setupWithNavController(navController)
}
}
Layout
<?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment
android:id="#+id/mainBottomNavHostFragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:defaultNavHost="false"
app:layout_constraintBottom_toTopOf="#+id/bottomNavigation"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="#navigation/main_menu_nav_graph" />
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottomNavigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:menu="#menu/main_menu" />
</androidx.constraintlayout.widget.ConstraintLayout>
main_menu_nav_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"
android:id="#+id/main_bottom_nav_graph"
app:startDestination="#id/first">
<fragment
android:id="#+id/first"
android:name=".FirstFragment"
android:label="FirstFragment" />
<fragment
android:id="#+id/second"
android:name=".SecondFragment"
android:label="SecondFragment" />
<fragment
android:id="#+id/third"
android:name=".ThirdFragment"
android:label="ThirdFragment">
<action
... />
</fragment>
<navigation
android:id="#+id/fourth"
app:startDestination="#id/fourthFragment">
<fragment
android:id="#+id/fourthFragment"
android:name=".FourthFragment"
android:label="FourthFragment" />
<fragment
android:id="#+id/fourthFragmentA"
android:name=".FourthFragmentA"
android:label="FourthFragmentA" />
<fragment
android:id="#+id/fourthFragmentB"
android:name=".FourthFragmentB"
android:label="FourthFragmentB" />
</navigation>
</navigation>
Second Fragment looks like this:
class SecondFragment : Fragment() {
private lateinit var navController: NavController
override fun onStart() {
super.onStart()
if (!::navController.isInitialized) {
navController = Navigation.findNavController(requireActivity(), R.id.secondHostFragment)
val inflater = navController.navInflater
navController.setGraph(inflater.inflate(R.navigation.second_nav_graph), arguments)
}
binding.secondBottomNavigation.setupWithNavController(navController)
}
}
Layout
<?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/secondBottomNavigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:menu="#menu/second_menu" />
<fragment
android:id="#+id/secondHostFragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/secondBottomNavigation" />
</androidx.constraintlayout.widget.ConstraintLayout>
second_nav_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"
android:id="#+id/second_nav_graph"
app:startDestination="#id/secondA">
<fragment
android:id="#+id/secondA"
android:name=".SecondA"
android:label="SecondA">
<action
... />
</fragment>
<fragment
android:id="#+id/secondB"
android:name=".SecondB"
android:label="SecondB" />
</navigation>
Can I have two nested BottomNavigationView? In version 2.3.5 everything worked
I'm trying the jetpack navigation and can't show the navigation back button when I move to a new fragment.
NavigationActivity.kt
class NavActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_navigation)
val toolbar = findViewById<Toolbar>(R.id.toolbar)
setSupportActionBar(toolbar)
val host: NavHostFragment = supportFragmentManager
.findFragmentById(R.id.navigation_graph) as NavHostFragment? ?: return
// Set up Navigation
val navController = host.navController
setupActionBarWithNavController(navController)
setupBottomNavMenu(navController)
}
private fun setupActionBarWithNavController(navController: NavController) {
setupActionBarWithNavController(this, navController)
}
private fun setupBottomNavMenu(navController: NavController) {
findViewById<BottomNavigationView>(R.id.bottom_nav_view)?.let { bottomNavView ->
NavigationUI.setupWithNavController(bottomNavView, navController)
}
}
}
activity_navigation.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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".views.NavActivity">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_height="?attr/actionBarSize"
android:elevation="4dp"
android:background="?attr/colorPrimary"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
android:theme="#style/ThemeOverlay.AppCompat.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
android:layout_width="match_parent">
</androidx.appcompat.widget.Toolbar>
<fragment
android:id="#+id/navigation_graph"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:defaultNavHost="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/toolbar"
app:navGraph="#navigation/navigation_graph"/>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_nav_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:menu="#menu/menu_bottom_nav" />
navigation_graph.xml
<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"
app:startDestination="#+id/launcher_home">
<fragment
android:id="#+id/launcher_home"
android:name="com.noisyninja.androidlistpoc.views.main.MainFragment"
android:label="#string/app_name"
tools:layout="#layout/fragment_main">
<action
android:id="#+id/next_action"
app:destination="#+id/detailFragment"
app:enterAnim="#anim/slide_in_right"
app:exitAnim="#anim/slide_out_left"
app:popEnterAnim="#anim/slide_in_left"
app:popExitAnim="#anim/slide_out_right" />
</fragment>
<fragment
android:id="#+id/detailFragment"
android:name="com.noisyninja.androidlistpoc.views.detail.DetailFragment"
android:label="DetailFragment" />
</navigation>
code for navigation:
/**
* opens detail activity
*/
override fun showDetail(view: View, me: Me) {
var bundle = Bundle()
bundle.putString("key", "value")
Navigation.findNavController(view).navigate(R.id.next_action, bundle, null)
}
As above when navigation to the second fragment the toolbar goes missing entirely and doesn't show the back button.
Hitting the hardware back button also doesn't pop the detail view.
The first hit has no effect, the second hit quits the app.
Override this method in your Activity with nav_host_fragment
#Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
return NavigationUI.navigateUp(navController, mAppBarConfiguration)
|| super.onSupportNavigateUp();
}
Edit: Your DetailFragment contains the line
DataBindingUtil.setContentView<FragmentDetailBinding>(requireActivity(),
R.layout.fragment_detail)
which is resetting the content of your Activity to only be your fragment_detail layout, wiping out the NavHostFragment and everything else.
You should be using DataBindingUtil.bind<FragmentDetailBinding>(view)!! instead.
Original answer (you should still do this, but the above answer is actually what solves the problem)
Your ConstraintLayout is missing quite a few constraints (your views should be a vertical chain, where every app:layout_constraintTop_toBottomOf has an alternative app:layout_constraintBottom_toTopOf on the other element, etc.).
Since you have a single set of three vertically aligned items, you don't need a ConstraintLayout - just a LinearLayout is enough:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
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"
android:orientation="vertical"
tools:context=".views.NavActivity">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_height="?attr/actionBarSize"
android:elevation="4dp"
android:background="?attr/colorPrimary"
android:theme="#style/ThemeOverlay.AppCompat.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
android:layout_width="match_parent"/>
<fragment
android:id="#+id/navigation_graph"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
app:defaultNavHost="true"
app:navGraph="#navigation/navigation_graph"/>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_nav_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:menu="#menu/menu_bottom_nav" />
</LinearLayout>
I am trying to learn how to use the navigation controller. and the problem is, My app seems not responding, it takes a very long time to show the main activity, and I can't also press the back button (seems not active)
here is the screenshot of my navigation graph, I am trying to set the host fragment in my Main Activity, as you can see, it seems a little bit weird that the bottom navigation view and the toolbar seem double on the NavHostFragment.
here is the screenshot of my main activity:
here is my mainActivity xml:
<android.support.constraint.ConstraintLayout
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=".MainActivity">
<android.support.v7.widget.Toolbar
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="?attr/colorPrimary"
android:theme="?attr/actionBarTheme"
android:minHeight="?attr/actionBarSize"
android:id="#+id/toolbar"
app:layout_constraintTop_toTopOf="parent" app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"/>
<fragment
android:layout_width="0dp"
android:layout_height="0dp"
android:id="#+id/nav_host_fragment"
app:layout_constraintBottom_toTopOf="#+id/bottom_nav"
app:layout_constraintTop_toBottomOf="#+id/toolbar"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
android:name="androidx.navigation.fragment.NavHostFragment"
app:navGraph="#navigation/navigation_graph"
app:defaultNavHost="true"
/>
<android.support.design.widget.BottomNavigationView
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:background="#color/colorPrimary"
app:itemIconTint="#color/color_bottom_view_navigation"
app:itemTextColor="#color/color_bottom_view_navigation"
app:menu="#menu/menu_bottom_view"
app:labelVisibilityMode="labeled"
android:id="#+id/bottom_nav"/>
</android.support.constraint.ConstraintLayout>
and here is the xml of navigation 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/navigation_graph"
app:startDestination="#id/mainActivity">
<activity android:id="#+id/mainActivity" android:name="com.muchammadagunglaksana.navcontroller.MainActivity"
android:label="activity_main" tools:layout="#layout/activity_main"/>
</navigation>
and here is my MainActivity class:
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val navController = Navigation.findNavController(this, R.id.nav_host_fragment)
setupBottomNavMenu(navController)
setupActionBar(navController)
}
private fun setupBottomNavMenu(navController: NavController) {
bottom_nav?.let {
NavigationUI.setupWithNavController(it, navController)
}
}
private fun setupActionBar(navController: NavController) {
NavigationUI.setupActionBarWithNavController(this, navController)
}
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
menuInflater.inflate(R.menu.menu_toolbar, menu)
return true
}
}
what went wrong in here?
It is because you are adding the same activity(mainActivity) as your start destination inside nav host fragment that is also part of main activity.
Solution is you have to remove main activty as your starting destination and add anotehr fragment/activity in it. like this:
<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/navigation_graph"
app:startDestination="#id/mainFragment">
<fragment android:id="#+id/mainFragment"
android:name="com.cinderellaman.general.ui.fragments.MainFragment"
android:label="main_fragment"
tools:layout="#layout/main_fragment"/></navigation>
I'm trying the jetpack navigation and can't show the navigation back button when I move to a new fragment.
NavigationActivity.kt
class NavActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_navigation)
val toolbar = findViewById<Toolbar>(R.id.toolbar)
setSupportActionBar(toolbar)
val host: NavHostFragment = supportFragmentManager
.findFragmentById(R.id.navigation_graph) as NavHostFragment? ?: return
// Set up Navigation
val navController = host.navController
setupActionBarWithNavController(navController)
setupBottomNavMenu(navController)
}
private fun setupActionBarWithNavController(navController: NavController) {
setupActionBarWithNavController(this, navController)
}
private fun setupBottomNavMenu(navController: NavController) {
findViewById<BottomNavigationView>(R.id.bottom_nav_view)?.let { bottomNavView ->
NavigationUI.setupWithNavController(bottomNavView, navController)
}
}
}
activity_navigation.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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".views.NavActivity">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_height="?attr/actionBarSize"
android:elevation="4dp"
android:background="?attr/colorPrimary"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
android:theme="#style/ThemeOverlay.AppCompat.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
android:layout_width="match_parent">
</androidx.appcompat.widget.Toolbar>
<fragment
android:id="#+id/navigation_graph"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:defaultNavHost="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/toolbar"
app:navGraph="#navigation/navigation_graph"/>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_nav_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:menu="#menu/menu_bottom_nav" />
navigation_graph.xml
<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"
app:startDestination="#+id/launcher_home">
<fragment
android:id="#+id/launcher_home"
android:name="com.noisyninja.androidlistpoc.views.main.MainFragment"
android:label="#string/app_name"
tools:layout="#layout/fragment_main">
<action
android:id="#+id/next_action"
app:destination="#+id/detailFragment"
app:enterAnim="#anim/slide_in_right"
app:exitAnim="#anim/slide_out_left"
app:popEnterAnim="#anim/slide_in_left"
app:popExitAnim="#anim/slide_out_right" />
</fragment>
<fragment
android:id="#+id/detailFragment"
android:name="com.noisyninja.androidlistpoc.views.detail.DetailFragment"
android:label="DetailFragment" />
</navigation>
code for navigation:
/**
* opens detail activity
*/
override fun showDetail(view: View, me: Me) {
var bundle = Bundle()
bundle.putString("key", "value")
Navigation.findNavController(view).navigate(R.id.next_action, bundle, null)
}
As above when navigation to the second fragment the toolbar goes missing entirely and doesn't show the back button.
Hitting the hardware back button also doesn't pop the detail view.
The first hit has no effect, the second hit quits the app.
Override this method in your Activity with nav_host_fragment
#Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
return NavigationUI.navigateUp(navController, mAppBarConfiguration)
|| super.onSupportNavigateUp();
}
Edit: Your DetailFragment contains the line
DataBindingUtil.setContentView<FragmentDetailBinding>(requireActivity(),
R.layout.fragment_detail)
which is resetting the content of your Activity to only be your fragment_detail layout, wiping out the NavHostFragment and everything else.
You should be using DataBindingUtil.bind<FragmentDetailBinding>(view)!! instead.
Original answer (you should still do this, but the above answer is actually what solves the problem)
Your ConstraintLayout is missing quite a few constraints (your views should be a vertical chain, where every app:layout_constraintTop_toBottomOf has an alternative app:layout_constraintBottom_toTopOf on the other element, etc.).
Since you have a single set of three vertically aligned items, you don't need a ConstraintLayout - just a LinearLayout is enough:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
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"
android:orientation="vertical"
tools:context=".views.NavActivity">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_height="?attr/actionBarSize"
android:elevation="4dp"
android:background="?attr/colorPrimary"
android:theme="#style/ThemeOverlay.AppCompat.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
android:layout_width="match_parent"/>
<fragment
android:id="#+id/navigation_graph"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
app:defaultNavHost="true"
app:navGraph="#navigation/navigation_graph"/>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottom_nav_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:menu="#menu/menu_bottom_nav" />
</LinearLayout>