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Add Menu to Activity's supportToolBar from a Fragment

I have an Activity with a Toolbar that I set as the supportActionBar. From this Activity I have various Fragments each with a customized ActionBar. I am able to call menu.clear() to remove the existing Menu but I am however unable to add another Menu in the same Fragment. This seems strange because menu.clear() behaves just as I would expect, but when calling inflater.inflate(R.menu.my_custom_menu,menu); appears to do nothing.
Example Fragment where I wish to modify the supportActionBar:
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
actionBar = ((AppCompatActivity)getActivity()).getSupportActionBar();
mGroupViewModel =
ViewModelProviders.of(requireActivity()).get(GroupsViewModel.class);
}
...
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
//Inflating seems to do nothing.
Log.i(TAG,"IN THE ONCREATEOPTIONSMENU FOR FRAGMENT.");
inflater.inflate(R.menu.group_edit_toolbar,menu);
super.onCreateOptionsMenu(menu, inflater);
}
#Override
public void onPrepareOptionsMenu(Menu menu) {
Log.i(TAG,"ONPREPARE OPTIONS MENU IN FRAGMENT.");
menu.clear();
super.onPrepareOptionsMenu(menu);
}
Clearly there is something I don't understand but I can't narrow down on what that problem is.
Would a better approach be to have each Fragment have their own Toolbar instead of all my fragments modifying the hosting activity's supportActionBar?
UPDATE
After further testing, I notice that if I try to assign a local MenuItem in my Fragment, I receive a null pointer exception unless I first inflate a menu in the Fragment itself. This is leading me to think that I am not hijacking control of the Activity's supportActionBar in the Fragment, but rather am trying to create a separate ActionBar for the Fragment. Would anyone be able to supplement my thinking here?
Fragment's menu callbacks:
MenuItem editItem;
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
Log.i(TAG,"IN ONCREATEOPTIONS");
menu.clear();
//MUST INFLATE MENU OTHERWISE WE GET NULL ERROR.
inflater.inflate(R.menu.home_actionbar,menu);
editItem = menu.findItem(R.id.action_edit_group);
Log.i(TAG,"edititem: "+editItem.getItemId());
super.onCreateOptionsMenu(menu, inflater);
}
// This is called every time the Menu opens.
#Override
public void onPrepareOptionsMenu(Menu menu) {
Log.i(TAG,"IN THE on prepare FOR FRAGMENT.");
menu.findItem(R.id.action_create_group).setVisible(false);
menu.findItem(R.id.action_create_group).setEnabled(false);
if(owner.equals(currUser)){
menu.findItem(R.id.action_edit_group).setEnabled(true);
menu.findItem(R.id.action_edit_group).setVisible(true);
} else {
menu.findItem(R.id.action_edit_group).setVisible(false);
menu.findItem(R.id.action_edit_group).setEnabled(false);
}
super.onPrepareOptionsMenu(menu);
}

onPrepareOptionsMenu is always called after onCreateOptionsMenu and there you're deleting your recently inflated menu!
Just delete onPrepareOptionsMenu and it should work fine.

Working with OptionsMenu in nested fragment not updating

I displayed a fragment A that implements a ViewPager with several fragments (nested fragments).
In my nested fragments, I inflate a menu with the following method.
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.my_menu, menu);
super.onCreateOptionsMenu(menu, inflater);
}
This question was already asked here. And i tried all the answers its not working.
My issue is
Everything working fine.but when i open another fragment(it have not any option menu) and get back to previous view pager fragment while clicking menu item onOptionsItemSelected not firing. When i swipe fragment in viewpager and come back to the previous one, when i click menu item its firing.

Its because viewpager maintain 3 fragment alive at a time. so when you come back, it set menu visibility status true to last fragment. thats why your menu item click not firing.
Use the following in the fragment where you keeping a viewpager in your case fragment A.
private boolean isInitial=true;
#Override
public void onResume() {
super.onResume();
if (!isInitial) {
int pos = viewpager.getCurrentItem();
if (pageAdapter.getItem(pos).getUserVisibleHint() && pageAdapter.getItem(pos).isVisible()) {
pageAdapter.getItem(pos).setMenuVisibility(true);
}
} else {
isInitial = false;
}
}

OptionsMenu of Fragments in Viewpager showing each other's Buttons

I've got three fragments in a viewpager.
Two of these fragments have their own version of the onCreateOptionsMenu method:
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
// Set up 1 action button
inflater.inflate(R.menu.home_snapshot_add, menu);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
// Set up 2 action buttons
inflater.inflate(R.menu.home_snapshot_send, menu);
}
The home activity has a basic onCreateOptionsMenu method:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
return false;
}
In the onCreate method, each fragment calls the method:
setHasOptionsMenu(true);
Each of the menu items have the tag:
android:showAsAction="always"
Seems like as I open the Activity, all three buttons appear.
However, when I scroll through them, the wrong ones magically disappear.
It feels like the activity is calling every Fragment's options menu on Activity creation and then changes the menu appropriately when I swipe left and right.
I've checked the menus but not sure what's wrong.
Anything you reckon I need to check? I'm a little out of ideas.
Thanks!

In your ViewPager's OnPageChangeListener and after setting the adapter to the ViewPager, have this:
#Override
public void onPageSelected(int position){
invalidateFragmentMenus(position);
}
private void invalidateFragmentMenus(int position){
for(int i = 0; i < mViewPagerFragentAdapter.getCount(); i++){
mViewPagerAdapter.getItem(i).setHasOptionsMenu(i == position);
}
invalidateOptionsMenu(); //or respectively its support method.
}
After setting your fragment adapter call the same method with following argument:
invalidateFragmentMenus(mViewPager.getCurrentItem());
The above statements will prevent all other fragments not to receive call on onCreateOptionsMenu() method when invalidateOptionsMenu() is called, only the currently visible fragment will receive and be able to populate the options menu.

I've used this and it has worked for me:
//In your Fragment
#Override
public void onResume() {
super.onResume();
setHasOptionsMenu(isVisible());
}

How to hide OptionsMenu on NavigationDrawer using Fragments?

I am creating android application and I'm trying to respect as much as possible the latest Android usability standards. In particular, I am preparing the user interface using the navigation drawer, and I'm trying to ensure compatibility with 2.1+ Android versions. To appreciate the problem, the project consists of:
A main activity;
A navigation drawer;
Four fragments (with their associated layouts).
The problem I'm experiencing occurs when opening the navigation drawer: although each Fragment has its specific menu, when I open the navigation drawer it is added to the nav drawer menu. I tried in several ways (invalidateOptionMenu(), menu.clear(), manipulating functions isDrawerOpen() and isDrawerClose() and more), but I cannot remove the Fragment's menu when opening the navigationdrawer.
These are some snippets of my code, much of it generated by Android Studio, the IDE I'm using:
In main activity:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this screen
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
getMenuInflater().inflate(R.menu.global, menu);
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
where "global" is a simple menu with a classical "ic_action_overflow".
And in my fragments I've:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
#Override
public void onPrepareOptionsMenu(Menu menu) {
super.onPrepareOptionsMenu(menu);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
inflater.inflate(R.menu.fragment1, menu);
}
(It's the same of the other Fragments).
Someone can give me some advice on how to act?

I faced the same problem using the boilerplate code generated by Android Studio and got it working by modifying the menu in NavigationDrawerFragment.onPrepareOptionsMenu() (in my case, I wanted to clear the menu altogether):
#Override
public void onPrepareOptionsMenu(Menu menu) {
if (mDrawerLayout != null && isDrawerOpen()) {
menu.clear();
}
}
This is roughly how the options menu is recreated:
NavigationDrawerFragment, which is generated by the IDE, calls supportInvalidateOptionsMenu() when the drawer is opened or closed.
onCreateOptionsMenu gets called: The hosting activity and each of the added fragments gets a chance to contribute menu items.
onPrepareOptionsMenu gets called: Again, the hosting activity and each of the added fragments get a chance to modify the menu.
The fragments are iterated in the order they were added. There is no way to stop the chain of calls midway in steps 2. and 3.
So the idea is to let NavigationDrawerFragment do last-minute changes to the menu in its onPrepareOptionsMenu and no other fragments.
If you need to let other fragments do something in onPrepareOptionsMenu, then you may have to setup those other fragments so they can determine if the drawer is open or not and change their behavior accordingly. This may mean perhaps adding a isDrawerOpen method to the hosting activity or passing in the drawer identifiers to the fragment like it's done in NavigationDrawerFragment.setup().

In your fragment onCreate, add this :
setHasOptionsMenu (true);
And then hide through onPrepareOptionsMenu. e.g.
#Override
public void onPrepareOptionsMenu(Menu menu) {
super.onPrepareOptionsMenu(menu);
menu.findItem(R.id.action_settings).setVisible(false);
}

If you've implemented the navigation drawer the way Android Studio sets it up for you in its example code with a NavigationDrawerFragment, you should have two xml to start with main.xml (activity wide actionbar menu items) and global.xml (global items). I then added a fragment specific menu which adds items to the "activity menu items" as long as the drawer is closed...
Activity:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this activity
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
getMenuInflater().inflate(R.menu.main, menu);
this.menu = menu;
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
NavigationDrawerFragment
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
// If the drawer is open, show the global app actions in the action bar.
// See also showGlobalContextActionBar, which controls the top-left area
// of the action bar.
if (mDrawerLayout != null && isDrawerOpen()) {
inflater.inflate(R.menu.global, menu);
showGlobalContextActionBar();
}
super.onCreateOptionsMenu(menu, inflater);
}
and in your fragments add as you've described above
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
// Add fragment specific action bar items to activity action bar items.
// Activity wide items are in main.xml
// Visible action bar items if navigation drawer is visible/open
// are in global.xml
super.onCreateOptionsMenu(menu, inflater);
if (!mNavigationDrawerFragment.isDrawerOpen()) {
inflater.inflate(R.menu.fragment_menu, menu);
}
}

Check out this answer here: https://stackoverflow.com/a/18135409/2558344. Its basically using a boolean to clear items in the navigation drawer and vice versa. But alternatively, you could declare Menu menu as a private variable in your class and use it as: onCreateOptionsMenu(menu, MenuInflater inflater).
Then check in your fragments onStop(), onPause() if it's displaying items or not, if yes then clear them, like:
if (menu != null)
menu.clear();

Access Fragment's Menu within a FragmentStatePagerAdapter

I use a FragmentStatePagerAdapter to display fragments inside a ViewPager.
These fragments display 2 additional icons on top of the ones coming from the parent Activity.
These 2 icons are showed/hidden according to fragment displayed, so I tried to keep the Menu inflated in memory in order to modify it dynamically.
On my ViewPager, 3 fragments are always loaded, only the middle one is displayed.
The problem is the following: it seems that onCreateOptionsMenu and onPrepareOptionsMenu are called only for the first Fragment created, because of this, I get null pointers when I try to get the menu on the other fragments. Please see the code below:
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
//Get the 2 icons for the rates
inflater.inflate(R.menu.rate_fragment, menu);
//Get activity's icons
super.onCreateOptionsMenu(menu, inflater);
mMenu = menu;
}
Here are the functions I use to hide/show the menu items:
private void hideOption(int id){
MenuItem item = mMenu.findItem(id);
if(item != null){
item.setVisible(false);
}
}
private void showOption(int id){
MenuItem item = mMenu.findItem(id);
if(item != null){
item.setVisible(true);
}
}
But these functions fail as soon as the system tries to load the second Fragment.
My guess is that the menu is only created once for the FragmentStatePagerAdapter, but then how can I modify dynamically the menu? Do I have to modify it using the Activity?
Thanks!