Develop Reference

How to avoid reinflating menu in fragments with AppBarLayout?

I inflate my SearchView into my AppBarLayout and MaterialToolbar in MainActivity. When I search items in ListFragment and open DetailFragment for an item then get back my AppBarLayout inflates again and I see my list is cleared. I want it to save query and show my previous state.
In ListFragment I do:
override fun onCreateOptionsMenu(menu: Menu, menuInflater: MenuInflater) {
menuInflater.inflate(R.menu.menu_main, menu)
}
override fun onPrepareOptionsMenu(menu: Menu) {
super.onPrepareOptionsMenu(menu)
setupSearchView(menu)
}
private fun setupSearchView(menu: Menu) {
userSearchView = menu.findItem(R.id.search).actionView as SearchView
userSearchView?.setOnQueryTextListener(object : SearchView.OnQueryTextListener {
override fun onQueryTextSubmit(query: String?): Boolean {
query?.let(viewModel::trySearching)
return true
}
override fun onQueryTextChange(newText: String?): Boolean {
newText?.let(viewModel::trySearching)
return true
}
})
}
In DetailFragment I do:
override fun onPrepareOptionsMenu(menu: Menu) {
super.onPrepareOptionsMenu(menu)
menu.clear()
}
For navigation I use AAC nav component

Back arrow won't trigger onOptionsItemSelected

I want add confirmation dialog before my fragment close. I have added the onOptionsItemSelected function in my fragment. however when i click the back arrow button the function is not executed. Here's my code
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
(activity as AppCompatActivity).supportActionBar?.show()
(activity as AppCompatActivity).supportActionBar?.setDisplayHomeAsUpEnabled(true)
(activity as AppCompatActivity).supportActionBar?.setDisplayShowHomeEnabled(true)
setHasOptionsMenu(true)
}
override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
inflater.inflate(R.menu.menu_input, menu)
return super.onCreateOptionsMenu(menu, inflater)
}
override fun onOptionsItemSelected(item: MenuItem): Boolean {
when (item.itemId) {
android.R.id.home -> "testing".debugTag("Debug")
}
return super.onOptionsItemSelected(item)
}

Try to set the action bar in onCreate.
setSupportActionBar( yourActionBar );

How to set a click listener on overflow menu - Material Toolbar

I would like to open the settings activity just by clicking on the overflow button in my Material Toolbar.
How can I setup a click listener on this button ? I don't want to inflate any menu by clicking on it, I just want to load another activity.
Before redesigning my app, I was inflating a menu by overriding onCreateOptionsMenu, but now I can't find any method to override that looks like onOverflowIconClickListener, or something like this.
I hope my question was clear enough.

All the answers are found here Menu
override fun onCreateOptionsMenu(menu: Menu): Boolean {
val inflater: MenuInflater = menuInflater
inflater.inflate(R.menu.game_menu, menu)
return true
}
override fun onOptionsItemSelected(item: MenuItem): Boolean {
// Handle item selection
return when (item.itemId) {
R.id.new_game -> {
newGame()
true
}
R.id.help -> {
showHelp()
true
}
else -> super.onOptionsItemSelected(item)
}
}

OptionsMenu in nested fragments with Nav component

I'm using Navigation Architecture Component
and nested fragments (only 1 activity in my app and shared ToolBar). In fragment A I do:
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
setHasOptionsMenu(true)
}
override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
super.onCreateOptionsMenu(menu, inflater)
inflater.inflate(R.menu.scan_menu, menu)
}
Then I show a new fragment B using something like this:
findNavController().navigate(R.id.action_a_b)
The navigation part of it works fine, but the menu created in fragment A sticks around when fragment b is shown (actually, it is never cleared). Isn't this supported in the nav arch components? How am I supposed to attack this? I do not wan't to perform hacks by clearing the menu manually in literally all other fragment due to one of them adding a menu.
Thanks!

Since there doesn't seem to be any solution, I ended up with keeping a reference to the MenuItem, and hide/show:
private var menuItem: MenuItem? = null
override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
super.onCreateOptionsMenu(menu, inflater)
inflater.inflate(R.menu.scan_menu, menu)
menuItem = menu.findItem(R.id.scan_menu_manual)
}
override fun onResume() {
super.onResume()
menuItem?.isVisible = true
}
override fun onPause() {
super.onPause()
menuItem?.isVisible = false
}
That seems to work for now.

setSupportActionBar inside of a Fragment

I have a Fragment:
class HomeFragment : Fragment() { ... }
Now I'm trying to add an Actionbar to it, but this doesn't work:
setSupportActionBar(findViewById(R.id.toolbar_main))
How can I set the Support and then add Items to the ActionBar?
This is how it works in an AppCompatActivity:
// This adds items to the ActionBar
override fun onCreateOptionsMenu(menu: Menu): Boolean {
menuInflater.inflate(R.menu.menu_toolbar_main, menu)
return true
}
// This is the OnClickListener for the Buttons in the ActionBar
override fun onOptionsItemSelected(item: MenuItem) = when (item.itemId) {
R.id.toolbar_edit -> {
true
}
R.id.toolbar_search -> {
true
}
else -> {
// If we got here, the user's action was not recognized.
// Invoke the superclass to handle it.
super.onOptionsItemSelected(item)
}
}
Big thanks in advance!

Override onCreateOptionsMenu in your Fragment and inflate your menu inside. Than in onCreate method of Fragment set setHasOptionsMenu() to true. To inflate different menus depending on Fragment creation clear the menu first.
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setHasOptionsMenu(true)
}
override fun onCreateOptionsMenu(menu: Menu?, inflater: MenuInflater?) {
super.onCreateOptionsMenu(menu, inflater)
inflater?.inflate(Your menu here, menu)
}