Android: Navigation Component - How to connect Toolbar menu to the fragments? - android

Iv been stuck in trying to add the Navigation Component to my app. Specifically to my toolbar menu items.
I have been following the navigation migrate documentation on Android's site but I am getting a but confused on how it works or even to set it up.
This is a single-activity multi-fragment architecture.
The app would start in the MainFragment and then when tapping the menu items in the toolbar, such as Main Frag to Search Movie Frag. The user would be able to navigate using the menu items from anywhere in the app (e.g. if they click the home icon, they should be sent to the home screen form anywhere in the app. Still thinking if thats how it should be done).
The main thing is I don't know how to properly attach the Navigation Component to the menu items.
App
Nav Graph
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/nav_graph"
app:startDestination="#id/mainFragment">
<fragment
android:id="#+id/mainFragment"
android:name="com.example.movieapp.ui.main.MainFragment"
android:label="MainFragment">
<action
android:id="#+id/action_mainFragment_to_searchMovieFragment"
app:destination="#id/searchMovieFragment" />
</fragment>
<fragment
android:id="#+id/searchMovieFragment"
android:name="com.example.movieapp.ui.search.SearchMovieFragment"
android:label="SearchMovieFragment" />
</navigation>
main_activity.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".activity.MainActivity">
<include
layout="#layout/appbar"
android:id="#+id/mainToolBar"/>
<androidx.fragment.app.FragmentContainerView
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="#id/mainToolBar"
app:layout_constraintBottom_toBottomOf="parent"
app:defaultNavHost="true"
app:navGraph="#navigation/nav_graph" />
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity.kt
class MainActivity : AppCompatActivity() {
private lateinit var toolbar: Toolbar
private val navController by lazy {
(supportFragmentManager.findFragmentById(R.id.nav_host_fragment) as NavHostFragment).navController
}
private lateinit var appBarConfiguration: AppBarConfiguration
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.main_activity)
toolbar = findViewById(R.id.mainToolBar)
setSupportActionBar(toolbar)
appBarConfiguration = AppBarConfiguration(navController.graph, null)
setupActionBarWithNavController(navController, appBarConfiguration)
}
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
val inflater: MenuInflater = menuInflater
inflater.inflate(R.menu.main_menu_bar, menu)
return true
}
override fun onSupportNavigateUp(): Boolean {
return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
}
MainFragment.kt
class MainFragment : Fragment() {
companion object {
fun newInstance() = MainFragment()
}
private lateinit var viewModel: MainViewModel
private lateinit var binding: MainFragmentBinding
private lateinit var navController: NavController
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
binding = DataBindingUtil.inflate(inflater, R.layout.main_fragment, container, false)
setHasOptionsMenu(true)
return binding.root
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
navController = Navigation.findNavController(view)
// navController.navigate(R.id.action_mainFragment_to_searchMovieFragment)
}
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
viewModel = ViewModelProvider(this).get(MainViewModel::class.java)
binding.viewModel = viewModel
// TODO: Use the ViewModel
}
}
main_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="viewModel"
type="com.example.movieapp.ui.main.MainViewModel" />
</data>
<LinearLayout
android:orientation="vertical"
android:id="#+id/main_fragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ui.main.MainFragment">
<TextView
android:id="#+id/message"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="MainFragment1" />
</LinearLayout>
</layout>

The id for a menu item in your file main_menu_bar.xml needs to match the id for the destination(fragment) specified in your navigation graph (nav_graph.xml).
Your main_menu_bar.xml should look something like this:
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
tools:showIn="navigation_view">
<group android:checkableBehavior="single">
<item
android:id="#id/searchMovieFragment"
android:icon="#drawable/search"
android:title="#string/menu_search" />
<item
android:id="#id/mainFragment"
android:icon="#drawable/ic_menu_camera"
android:title="#string/menu_home" />
</group>
</menu>
Also, you need to override the onOptionsItemSelected(MenuItem) method and associate your menu items with destinations. Like so:
override fun onOptionsItemSelected(item: MenuItem): Boolean {
val navController = findNavController(R.id.nav_host_fragment)
return item.onNavDestinationSelected(navController) || super.onOptionsItemSelected(item)
}
Reference

You can add a Toolbar on top of the most basic FragmentContainerView, access this toolbar from other fragments, and change the toolbar I created separately according to the fragment in it while opening the relevant fragment as follows.
toolbar = requireActivity().findViewById(R.id.toolbar_base)
toolbar?.menu?.clear()
toolbar?.title = ""
val toolbarFlowFragment = context?.let { getInflateLayout(it, R.layout.toolbar_profile) }
toolbar?.addView(toolbarFlowFragment)

Related

How can I use Navigation (NavHost) in nested fragments?

I'm trying to open Fragment2 from Fragment1(TransformFragment)
throught click item in RecyclerView. I tried to use Navigation (NavHost) to solve this problem.
Fragment1 code as below:
class TransformFragment : Fragment() {
private lateinit var transformViewModel: TransformViewModel
private var _binding: FragmentTransformBinding? = null
// This property is only valid between onCreateView and
// onDestroyView.
private val binding
get() = _binding!!
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
transformViewModel = ViewModelProvider(this)[TransformViewModel::class.java]
_binding = FragmentTransformBinding.inflate(inflater, container, false)
val root: View = binding.root
val recyclerView = binding.recyclerviewTransform
val adapter = TransformAdapter()
recyclerView.adapter = adapter
transformViewModel.texts.observe(viewLifecycleOwner) { adapter.submitList(it) }
return root
}
override fun onDestroyView() {
super.onDestroyView()
_binding = null
}
class TransformAdapter() :
ListAdapter<String, TransformViewHolder>(
object : DiffUtil.ItemCallback<String>() {
override fun areItemsTheSame(oldItem: String, newItem: String): Boolean =
oldItem == newItem
override fun areContentsTheSame(oldItem: String, newItem: String): Boolean =
oldItem == newItem
}
) {
private val drawables =
listOf(
R.drawable.avatar_1,
R.drawable.avatar_2,
R.drawable.avatar_3,
R.drawable.avatar_4,
R.drawable.avatar_5,
R.drawable.avatar_6,
R.drawable.avatar_7,
R.drawable.avatar_8,
R.drawable.avatar_9,
R.drawable.avatar_10,
R.drawable.avatar_11,
R.drawable.avatar_12,
R.drawable.avatar_13,
R.drawable.avatar_14,
R.drawable.avatar_15,
R.drawable.avatar_16,
R.drawable.avatar_17,
)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): TransformViewHolder {
val binding = ItemTransformBinding.inflate(LayoutInflater.from(parent.context))
return TransformViewHolder(binding)
}
override fun onBindViewHolder(holder: TransformViewHolder, position: Int) {
holder.textView.text = getItem(position)
holder.imageView.setImageDrawable(
ResourcesCompat.getDrawable(holder.imageView.resources, drawables[position], null)
)
holder.itemView.setOnClickListener {
// my navigation(NavHost) code
}
}
}
class TransformViewHolder(binding: ItemTransformBinding) :
RecyclerView.ViewHolder(binding.root) {
val imageView: ImageView = binding.imageViewItemTransform
val textView: TextView = binding.textViewItemTransform
}
}
I tried to use this:
val navController = findNavController(R.id.nav_host_fragment_content_main)
navController.navigate(R.id.nav_detail)
nav_detail to navigate Fragment2, and My Fragment Container. This's my XML. I know that to display Dynamiclly Fragments, you must use FrameLayout, but it produces errors and the fragment container is OK.
<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"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:showIn="#layout/app_bar_main">
<fragment
android:id="#+id/nav_host_fragment_content_main"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginLeft="#dimen/fragment_horizontal_margin"
android:layout_marginRight="#dimen/fragment_horizontal_margin"
android:layout_weight="1"
app:defaultNavHost="true"
app:navGraph="#navigation/mobile_navigation" />
<!--
<FrameLayout
android:id="#+id/nav_host_fragment_content_main"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginLeft="#dimen/fragment_horizontal_margin"
android:layout_marginRight="#dimen/fragment_horizontal_margin"
android:layout_weight="1"
app:defaultNavHost="true"
app:navGraph="#navigation/mobile_navigation" />
-->
</LinearLayout>
I've found the correct answer in Android developers documentation.
holder.itemView.setOnClickListener {
it.findNavController().navigate(R.id.nav_detail)
}
To use findNavController() to navigate between fragments, you've to make sure that you've setup with activity properly first.
So, in your activity layout first add container, parent need nod to be FrameLayout itself, I'm gonna make use of ConstraintLayout below.
activity_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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<!-- We declare attribute id to hook with MainActivity.java class-->
<!-- Attribute name will change behavior of simple fragment to NavHostFragment-->
<!-- Keep width and height to match_parent so that all our fragments take whole space-->
<!-- We change this NavHost to behave default NavHost-->
<!-- Attach our app navigation graph to this NavHostFragment-->
<fragment
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="#navigation/nav_graph" />
</androidx.constraintlayout.widget.ConstraintLayout>
Now let's hook container as an acting host for activity.
MainActivity.kt
class MainActivity : AppCompatActivity() {
lateinit var navController: NavController
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// NavigationController to set default NavHost as nav_host_fragment.
navController = Navigation.findNavController(this, R.id.nav_host_fragment)
NavigationUI.setupActionBarWithNavController(this, navController)
}
override fun onSupportNavigateUp(): Boolean {
return navController.navigateUp()
}
}
onSupportNavigateUp function helps you to navigate back to previous fragment on action trigered or called specifically on any view with navigateUp().
Now you want to navigate from Fragment1 -> Fragment2.
Make sure you've added two fragments to navigation graph.
Connect first fragment to second with action.
Keep track of destination Id's to call correct one.
<?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/nav_graph"
app:startDestination="#id/firstFragment">
<fragment
android:id="#+id/firstFragment"
android:name=".FirstFragment"
android:label="FirstFragment"
tools:layout="#layout/fragment_first">
<action
android:id="#+id/action_first_fragment_to_second_fragment"
app:destination="#id/secondFragment" />
</fragment>
<fragment
android:id="#+id/secondFragment"
android:name=".SecondFragment"
android:label="Authors"
tools:layout="#layout/fragment_second" />
</navigation>
Now finally once action is triggered call action with id like below on controller.
yourListItemView.setOnClickListener {
findNavController(R.id.action_first_fragment_to_second_fragment)
}
That's it.
Please check the documentation, it has a good information.

Cannot set Toolbar menu with NavigationDrawer

I'm trying to combine NavigationDrawer with a Toolbar that has a refresh Menu option:
The problem I'm encountering is that I cannot make the Toolbar show the menu button.
My MainActivity only holds a Fragment. activity_main.xml:
<androidx.fragment.app.FragmentContainerView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/main_nav_container"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="#navigation/main" />
MainActivity.kt:
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
}
}
nav_main:
<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_main"
app:startDestination="#id/drawerFragment"
>
<fragment
android:id="#+id/drawerFragment"
android:name="com.example.rocketman.drawer.DrawerFragment"
android:label="DrawerFragment"
tools:layout="#layout/fragment_drawer"
/>
</navigation>
Basically my MainActivity navigates directly into a DrawerFragment, which is here:
<androidx.drawerlayout.widget.DrawerLayout
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/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.rocketman.drawer.DrawerFragment">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.rocketman.drawer.DrawerFragment">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.google.android.material.appbar.MaterialToolbar
android:id="#+id/toolbar_home"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/midnight_blue"
app:titleTextColor="#color/white"/>
</com.google.android.material.appbar.AppBarLayout>
<androidx.fragment.app.FragmentContainerView
android:id="#+id/drawer_container"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
</LinearLayout>
<com.google.android.material.navigation.NavigationView
android:id="#+id/drawer_nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true"
app:headerLayout="#layout/drawer_header"
app:menu="#menu/drawer" />
</androidx.drawerlayout.widget.DrawerLayout>
And finally, my DrawerFragment:
private const val KEY_SELECTED_DRAWER_ITEM = "DRAWER_SELECTED_ITEM_ID_KEY"
class DrawerFragment: Fragment() {
private lateinit var binding: FragmentDrawerBinding
private var drawerSelectedItemId = R.id.nav_home
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
binding = FragmentDrawerBinding.inflate(inflater)
(requireActivity() as AppCompatActivity).setSupportActionBar(toolbar_home)
return binding.root
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
savedInstanceState?.let {
drawerSelectedItemId = it.getInt(KEY_SELECTED_DRAWER_ITEM, drawerSelectedItemId)
}
setupDrawer()
setBackPressedHandler()
}
private fun setBackPressedHandler() {
requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner) {
if (binding.drawerLayout.isOpen) {
binding.drawerLayout.close()
} else {
findNavController().popBackStack()
}
}
}
override fun onSaveInstanceState(outState: Bundle) {
outState.putInt(KEY_SELECTED_DRAWER_ITEM, drawerSelectedItemId)
super.onSaveInstanceState(outState)
}
private fun setupDrawer() {
val controller = binding.drawerNavView.setupWithNavController(
childFragmentManager,
findNavController(),
listOf(
//all the items on the Drawer have their own navigation graph
R.navigation.home,
R.navigation.rocket,
R.navigation.company
),
R.id.drawer_container,
drawerSelectedItemId,
requireActivity().intent
)
controller.observe(
viewLifecycleOwner,
{ navController ->
NavigationUI.setupWithNavController(
binding.toolbarHome,
navController,
binding.drawerLayout
)
drawerSelectedItemId = navController.graph.id
}
)
}
}
In other words, the Drawer has three items: home, rocket and company as can be seen here, menu/drawer:
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:id="#+id/nav_home"
android:checked="true"
android:checkable="true"
android:icon="#drawable/ic_home"
android:title="#string/nav_menu_home"
/>
<item
android:id="#+id/nav_rocket"
android:checkable="true"
android:icon="#drawable/ic_rocket"
android:title="#string/nav_menu_rocket_list"
/>
<item
android:id="#+id/nav_company"
android:checkable="true"
android:icon="#drawable/ic_company"
android:title="#string/nav_menu_company_data"
/>
</menu>
Each of home, rocket and company have their own navigation graph, for example navigation/company looks 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/nav_company"
app:startDestination="#id/companyDataFragment">
<fragment
android:id="#+id/companyDataFragment"
android:name="com.example.rocketman.company.CompanyFragment"
android:label="#string/nav_menu_company_data"
tools:layout="#layout/fragment_company_data"
/>
</navigation>
And the CompanyFragment is straight forward:
class CompanyFragment: Fragment() {
private lateinit var binding: FragmentCompanyDataBinding
private val vm by lazy {
ViewModelProvider(this).get(CompanyVM::class.java)
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setHasOptionsMenu(true)
Repo.init(requireContext())
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
binding = FragmentCompanyDataBinding.inflate(inflater)
return binding.root
}
override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
super.onCreateOptionsMenu(menu, inflater)
inflater.inflate(R.menu.company, menu)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
setupObservers()
}
private fun setupObservers() {
//observing
}
}
That part works.
However, I want to create a menu action for Company. So first I create a menu item menu/company:
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="#+id/update"
android:icon="#drawable/ic_baseline_refresh_24"
android:title="#string/menu_company_update"
app:showAsAction="ifRoom|withText"
/>
</menu>
Then in CompanyFragment I call override onCreate() { setHasOptionsMenu(true) } and override onCreateOptionsMenu() { inflater.inflate(R.menu.company, menu }.
This should create the options menu for the Toolbar. However, the Fragment only shows the drawer menu icon but not the options menu icon.
I can add a Toolbar to the content Fragment itself but then the app has two Toolbars, the one with the drawer and the one with option items:
How do I make the Toolbar have both the NavigationDrawer and option items?
Still many people continue to use ActionBar, we don't have to use it any more. And if I were you, I would not use ActionBar and setHasOptionsMenu(true) which is related to ActionBar, but just would use a Toolbar.
Just delete setHasOptionsMenu(true), onCreateOptionsMenu() and onOptionsItemSelected() (if you have it).
Instead, use Toolbar.inflateMenu() and Toolbar.setOnMenuItemClickListener() directly on your Toolbar.
From what I understand from your question, you want to display overflow menu along with drawer menu.
The showAsAction option in the menu xml file is what you can use to control how that single menu option will show up in the actionbar.
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="#+id/update"
android:icon="#drawable/ic_baseline_refresh_24"
android:title="#string/menu_company_update"
app:showAsAction="ifRoom|withText"
/>
</menu>
change this to
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="#+id/update"
android:icon="#drawable/ic_baseline_refresh_24"
android:title="#string/menu_company_update"
app:showAsAction="never"
/>
</menu>
This will show the menu item in the Overflow menu.

Android: How to open a Fragment with Navigation Graph without replacing the current Fragment

I am wondering if there is a way to add another fragment to the screen without replacing the old one with the Navigation Graph.
I want to do this because the new fragment will just be open for a bit just to check some details and when the user returns to the previous fragment, I want them to be in the same spot they left off.
I have read around but I couldn't find one that does it without replacing the original. I have tried to just add it to the nav_graph_fragment which I try to do this in the newFrag() function in the CurrentFragment section but it doesn't work.
Main Activty
class MainActivity : AppCompatActivity() {
private lateinit var toolbar: Toolbar
private val navController by lazy {
(supportFragmentManager.findFragmentById(R.id.nav_host_fragment) as NavHostFragment).navController
}
private lateinit var appBarConfiguration: AppBarConfiguration
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.main_activity)
toolbar = findViewById(R.id.mainToolBar)
setSupportActionBar(toolbar)
appBarConfiguration = AppBarConfiguration(navController.graph, null)
setupActionBarWithNavController(navController, appBarConfiguration)
}
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
val inflater: MenuInflater = menuInflater
inflater.inflate(R.menu.main_menu_bar, menu)
return true
}
override fun onSupportNavigateUp(): Boolean {
return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
override fun onOptionsItemSelected(item: MenuItem): Boolean {
val navController = findNavController(R.id.nav_host_fragment)
if (item.itemId == navController.currentDestination?.id)
return true
return item.onNavDestinationSelected(navController) || super.onOptionsItemSelected(item)
}
}
Main Activity xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".activity.MainActivity">
<include
layout="#layout/appbar"
android:id="#+id/mainToolBar"/>
<androidx.fragment.app.FragmentContainerView
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="#id/mainToolBar"
app:layout_constraintBottom_toBottomOf="parent"
app:defaultNavHost="true"
app:navGraph="#navigation/nav_graph" />
</androidx.constraintlayout.widget.ConstraintLayout>
CurrentFragment
class CurrentFragment : Fragment() {
private lateinit var currentFragmentViewModel: CurrentFragmentViewModel
private lateinit var binding: CurrentFragmentBinding
private lateinit var recyclerView: RecyclerView
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
binding = DataBindingUtil.inflate(inflater, R.layout.current_fragment, container, false)
currentFragmentViewModel = ViewModelProvider(this).get(CurrentFragmentViewModel::class.java)
binding.lifecycleOwner = this
binding.viewmodel = currentFragmentViewModel
binding.accountButton.setOnClickListener {
Log.d("TEST", "button clicked")
newFrag()
}
return binding.root
}
// Here is where I am trying to open the new fragment
private fun newFrag() {
val newFrag = Fragment()
val transaction: FragmentTransaction = parentFragmentManager.beginTransaction()
transaction.hide(this)
transaction.add(R.id.nav_host_fragment, newFrag).commit()
}
}
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"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/nav_graph"
app:startDestination="#id/mainFragment">
<fragment
android:id="#+id/mainFragment"
android:name="com.example.app.ui.main.MainFragment"
android:label="MainFragment">
<action
android:id="#+id/action_mainFragment_to_currentFragment"
app:destination="#id/currentFragment" />
</fragment>
<fragment
android:id="#+id/currentFragment"
android:name="com.example.app.ui.search.CurrentFragment"
android:label="currentFragment" >
</fragment>

Navigation Component - ActionBar handle in Activity only

I am finally adopting Navigation Architecture Components in a new project and I am already encountering some issues that the docs don't seem to address.
With an ActionBar menu setup in the activity, when I navigate to another fragment and then try to use the ActionBar menu I receive
java.lang.IllegalArgumentException: Navigation action/destination X cannot be found from the current destination
It would appear that I must also add actions from all possible destinations to goto all other destinations which seems like overkill, this just cannot be. There must be a solution to this problem that I am not finding.
I intend to open the app which inflates MainActivity and then MainFragment within the fragment element. The MainActivity should still handle top level navigation within the ActionBar. There is absolutely no reason I need to dupe menu click work in every fragment and define destinations to all other areas of the app.
MainActivity
class MainActivity : AppCompatActivity() {
private lateinit var navController: NavController
private lateinit var appBarConfiguration: AppBarConfiguration
private var menu: Menu? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val controller by lazy { findNavController(R.id.fragment_container) }
navController = controller
val appBarConfig by lazy { AppBarConfiguration(navController.graph) }
appBarConfiguration = appBarConfig
setSupportActionBar(toolbar)
setupActionBarWithNavController(navController, appBarConfiguration)
}
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
menuInflater.inflate(R.menu.appbar_menu, menu)
this.menu = menu
return true
}
override fun onOptionsItemSelected(item: MenuItem): Boolean {
var direction: NavDirections? = null
when(item.itemId) {
R.id.action_messages -> {
direction = MainFragmentDirections.actionMainFragmentToMessagesFragment()
}
R.id.action_menu -> {
direction = MainFragmentDirections.actionMainFragmentToMessagesFragment()
}
else -> super.onOptionsItemSelected(item)
}
if (direction != null) navController.navigate(direction)
return true
}
override fun onSupportNavigateUp(): Boolean {
return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
}
activity_main
<?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:id="#+id/card_id_test"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?actionBarSize"
android:background="#color/colorPrimary"
android:elevation="4dp"
android:clipToPadding="false"
app:menu="#menu/appbar_menu"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:titleTextColor="#color/white" />
<fragment
android:id="#+id/fragment_container"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
app:defaultNavHost="true"
app:navGraph="#navigation/nav_graph"
app:layout_constraintTop_toBottomOf="#+id/toolbar"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>
MainFragment
class MainFragment : Fragment() {
private var _binding: FragmentMainBinding? = null
private val binding get() = _binding!!
private var mActivity : MainActivity? = null
private var mView: View? = null
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
super.onCreateView(inflater, container, savedInstanceState)
_binding = FragmentMainBinding.inflate(inflater, container, false)
mView = binding.root
mActivity = (activity as MainActivity)
return mView
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
btn_dashboard.setOnClickListener {
findNavController().navigate(
MainFragmentDirections.actionMainFragmentToDashboardFragment())
}
}
}
fragment_main
<?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:id="#+id/content_test"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.appcompat.widget.AppCompatTextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:text="Main Fragment"
android:textSize="24dp" />
<com.google.android.material.button.MaterialButton
android:id="#+id/btn_dashboard"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="16dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:text="Dashboard" />
</androidx.constraintlayout.widget.ConstraintLayout>
DashboardFragment
class DashboardFragment : Fragment() {
private var _binding: FragmentDashboardBinding? = null
private val binding get() = _binding!!
private var mActivity : MainActivity? = null
private var mView: View? = null
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
super.onCreateView(inflater, container, savedInstanceState)
_binding = FragmentDashboardBinding.inflate(inflater, container, false)
mView = binding.root
mActivity = (activity as MainActivity)
return mView
}
}
fragment_dashboard
<?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:id="#+id/content_test"
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.appcompat.widget.AppCompatTextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:text="Dashboard Fragment"
android:textSize="24dp" />
</androidx.constraintlayout.widget.ConstraintLayout>
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/nav_graph"
app:startDestination="#id/mainFragment">
<fragment
android:id="#+id/mainFragment"
android:name="com.example.appbarnavigation.MainFragment"
android:label="Main" >
<action
android:id="#+id/action_mainFragment_to_messagesFragment"
app:destination="#id/action_messages" />
<action
android:id="#+id/action_mainFragment_to_menuFragment"
app:destination="#id/action_menu" />
<action
android:id="#+id/action_mainFragment_to_dashboardFragment"
app:destination="#id/dashboardFragment" />
</fragment>
<fragment
android:id="#+id/action_messages"
android:name="com.example.appbarnavigation.MessagesFragment"
android:label="Messages" />
<fragment
android:id="#+id/action_menu"
android:name="com.example.appbarnavigation.MenuFragment"
android:label="Menu" />
<fragment
android:id="#+id/dashboardFragment"
android:name="com.example.appbarnavigation.DashboardFragment"
android:label="Dashboard" />
</navigation>
appbar_menu
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="#+id/action_messages"
android:orderInCategory="1"
android:title="Messages"
android:icon="#drawable/ic_message"
app:showAsAction="always"/>
<item
android:id="#+id/action_menu"
android:orderInCategory="2"
android:title="Menu"
android:icon="#drawable/ic_menu"
app:showAsAction="always"/>
</menu>
This was resolved by defining and using global actions.
<?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/nav_graph"
app:startDestination="#id/mainFragment">
<fragment
android:id="#+id/mainFragment"
android:name="com.example.appbarnavigation.MainFragment"
android:label="Main" >
<action
android:id="#+id/action_mainFragment_to_dashboardFragment"
app:destination="#id/dashboardFragment" />
</fragment>
<fragment
android:id="#+id/action_messages"
android:name="com.example.appbarnavigation.MessagesFragment"
android:label="Messages" />
<fragment
android:id="#+id/action_menu"
android:name="com.example.appbarnavigation.MenuFragment"
android:label="Menu" />
<fragment
android:id="#+id/dashboardFragment"
android:name="com.example.appbarnavigation.DashboardFragment"
android:label="Dashboard" />
<action android:id="#+id/action_global_action_messages" app:destination="#id/action_messages" />
<action android:id="#+id/action_global_action_menu" app:destination="#id/action_menu" />
</navigation>
and in the MainActivity
override fun onOptionsItemSelected(item: MenuItem) = when(item.itemId) {
R.id.action_messages -> {
navController.navigate(R.id.action_global_action_messages)
true
}
R.id.action_menu -> {
navController.navigate(R.id.action_global_action_menu)
true
}
// This is used for menu buttons or anything not explicitly defined here
else -> {
super.onOptionsItemSelected(item)
}
}

Jetpack navigation does not navigate to other destination

I am using jetpack navigation in two different activities each with its navigation host. I have Main activity which everything just works fine and Setup activity which have 2 fragments, one has a button which should navigate to other fragment when clicked .
The activity's code is as follows:
class SetupActivity : AppCompatActivity() {
private val navController by lazy { findNavController(R.id.nav_host_fragment) }
private lateinit var appBarConfig: AppBarConfiguration
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
DataBindingUtil.setContentView<ActivitySetupBinding>(this, R.layout.activity_setup)
setSupportActionBar(toolbar)
appBarConfig = AppBarConfiguration(navController.graph)
setupActionBarWithNavController(navController, appBarConfig)
}
override fun onSupportNavigateUp(): Boolean {
return navController.navigateUp(appBarConfig) || super.onSupportNavigateUp()
}
}
Below is activity's 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"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context=".ui.SetupActivity"
tools:showIn="#layout/activity_setup">
<fragment
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="#navigation/setup" />
</androidx.constraintlayout.widget.ConstraintLayout>
Below is code of first fragment which is also a start Destination
class ConfirmClassFragment : Fragment() {
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val binding = FragmentConfirmClassBinding.inflate(inflater, container, false)
binding.fragment = this
return binding.root
}
fun navigate() {
toast("clicked") //this get called
val direction = ConfirmClassFragmentDirections.actionConfirmToSetup()
findNavController().navigate(direction) //THE PROBLEM IS HERE
//findNavController().navigate(R.id.setup)
}
}
I am using data binding to call fun navigate() as below:
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<variable
name="fragment"
type="com.nux.ui.fragments.ConfirmClassFragment" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="#dimen/spacing_middle">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="#{() -> fragment.navigate()}"
android:text="#string/continue_" />
</LinearLayout>
</layout>
and this how navigation xml looks like:
<?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/setup"
app:startDestination="#id/confirm">
<fragment
android:id="#+id/setup"
android:name="com.nux.ui.fragments.SetInfoFragment"
android:label="#string/setup"
tools:layout="#layout/fragment_set_info" />
<fragment
android:id="#+id/confirm"
android:name="com.nux.ui.fragments.ConfirmClassFragment"
android:label="#string/data_confirmation"
tools:layout="#layout/fragment_confirm_class">
<action
android:id="#+id/action_confirm_to_setup"
app:destination="#id/setup" />
</fragment>
</navigation>
When I click button fun gets called but nothing happens! What could be wrong?
From the code i can see you have the same id for 3 elements in the navigation graph.
#id/setup should only be used once and please change the name of the navigation graph from setup to something else.

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