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!
Related
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;
}
}
My question is how can I prevent that my programmatically created toolbar menuItem (Menu with submenus) gets overridden with the xml layout every time the fragment resumes.
I want to create my expensive toolbar menuitem only when fragment is first time created and not when it is resumes.
I inflat my toolbar in the onCreateOptionsMenu() and store an instance of the menu item.
private MenuItem menuItem;
private SubMenu expessiveSubmenu;
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu_layout, menu);
menuItem= menu.findItem(R.id.menuItem);
}
The menuItem gets populated when the async loader finishs.
#Override
public void onLoadFinished(Loader<> loader, Data data) {
//Expensive call
expensiveSubmenu= makeExpensiveSubMenu(menuItem, data);
}
Now the menu is fully populated and visible in the toolbar and I also have an instance of my submenu.
Because onCreateOptionsMenu() is called evertime the fragment is resumed my menu get's overridden with the xml layout and I have to create the expensive submenu again. A mehtod like menu.addSubmenu(Menu) would solve my needs but I couldn't find one. Any ideas would be appreciated.
I have been struggling to implement switching visibility of Share option on Menu between fragments. I am using sliding tab layout and has a fragment in each of the 2 tabs. First tab (uses list view) and when an item is selected, I am setting a flag as true and calls invalidateOptionsMenu() and it works fine by showing a share option on the App bar menu, but I am not able to cancel it when I move to the other fragment which has mainly preferences. Code is similar to the below.
public void setSharedIntentText(String text) {
sharedText = text;
if (shareOptionVisibility == false) {
shareOptionVisibility = true;
invalidateOptionsMenu();
}
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
// Locate MenuItem with ShareActionProvider
MenuItem shareItem = menu.findItem(R.id.menu_share);
// Fetch and store ShareActionProvider
mShareActionProvider = (ShareActionProvider) MenuItemCompat.getActionProvider(shareItem);
sendIntent.setAction(Intent.ACTION_SEND);
sendIntent.setType("text/plain");
sendIntent.putExtra(Intent.EXTRA_TEXT, sharedText);
mShareActionProvider.setShareIntent(sendIntent);
shareItem.setVisible(shareOptionVisibility);
When I switch between tabs, visibility should be set appropriately. I tried to set it onPause method of the first fragment, and then onResume method of second fragment, but control doesn't seem to go these methods when I look at the logcat. The code I have used to set visibility to false is as below in fragment2.
public void onResume() {
super.onResume();
Log.i(TAG, "On Resume ");
((MainActivity) getActivity()).shareOptionVisibility = false;
((MainActivity) getActivity()).invalidateOptionsMenu();
}
So would like to know where is the best place to put the code to control visibility when we switch between tabs. Here are the list of classes I use.
MainActivity, fragment1, fragment2, SlidingTabLayout, SlidingTabStrip and ViewPagerAdaptor. This code was implemented on top of the com.example.android.actionbarcompat.shareactionprovider example.
Thanks in advance
Issue now resolved by implementing the onCreateOptionsMenu method from the fragment rather than from the MainActivity.
Thanks
In my application the main activity hosts two fragments and attached to acticity as ActionBarTabs. using the following code. NOTE: activity and the 2 fragments are defined in seperate xml layout files (See the picture at the bottom)
private void createActionTabs() {
ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
//Status Tab
String strStatus = getResources().getString(R.string.lblStatus);
ActionBar.Tab statusTab = actionBar.newTab();
statusTab.setText(strStatus);
TabListener<SFrag> sFTabListener = new TabListener<SFrag>(this, strStatus, SFrag.class);
statusTab.setTabListener(sFTabListener);
actionBar.addTab(statusTab);
//Controller Tab attached the same way
.....
}
The ActionBar Items (start and refresh) are added using
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main_menu, menu);
return true;
}
Now coming to my problem:
I want to update the data shown on the Status Fragment at application load, fragment resume and click of refresh menu item from the action bar. Now when I try to access the Status fragment from Main Activity using the following code
SFrag frag = (SFrag) getFragmentManager().findFragmentById(R.id.st_frag);
Log.d(TAG, "In Activity SFrag is " + (frag == null ? "null" : "not null"));
if (frag != null) {
//calls the method to update data
fragment.updateStatusData(statusInformation);
}
The getFragmentManager().findFragmentById methods always returns null. I even tried the onResume method of the activity, the fragment objects is still returned as null. So how do I access the fragment and thus accessa method of that fragment from host acticty.
Secondly, I am trying to use the action_service (its shown as Start button just for this mockup) in action bar as a toggle for satrting or stopping a background service. I can easily update the title/icon for start menu item from onOptionsItemSelected method (I save the current status running/stoppede in shared-preferences). but when I try to accees the menuItem at onStart/onResume of the activity by using
MenuItem mi = (MenuItem) findViewById (R.id.action_service);
it always returns null. So How Can I access action_service menu Item in onResume/onStart to update it.
My Application looks like this
First of all if you want to declare MenuItem, you should do it in this way :
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getSupportMenuInflater().inflate(R.menu.main_activity, menu);
MenuItem mRefresh = menu.findItem(R.id.refresh_menu_item);
return true;
}
About updating your Fragment on applications load or Activity's start, just set selected the tab which holds your Fragment and put the code which will load the data in your Fragment on it's onStart() or onActivityCreated() method. You can override onOptionsItemSelected() in your Fragment, so you can update your views not from your Activity which holds your Fragment, but from it's own class.
Edit: Here is an example how you should handle menu from your Fragment :
public class MyFragment extends Fragment {
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setHasOptionsMenu(true); // Do not forget this!!!
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
inflater.inflate(R.menu.first_fragment, menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
super.onOptionsItemSelected(item);
switch (item.getItemId()) {
case R.id.action_refresh:
// Do You stuff here
break;
}
return super.onOptionsItemSelected(item);
}
}
Using this you can add and use MenuItem's in your Fragment.
Hope this helps!
I can answer the MenuItem part just not the other part.
for the menu item as per the docs You can safely hold on to menu (and any items created from it), making modifications to it as desired, until the next time onCreateOptionsMenu() is called.
for example
#Override
public boolean onCreateOptionsMenu(Menu menu) {
actionMenu = menu;
return true;
}
so basically anytime you want to change one of the items you can do this
MenuItem item = actionMenu.getItem(0);
I have a problem with FragmentStatePageAdapter (that I use as adapter for a ViewPager) and the menu items from the action bar.
When I launch the application, everything is fine. If I move the task to background (for example, pressing HOME button) and I start doing stuff until the activity is ended, then when I go back to my application (through the launcher or a notification I create) everything is fine except there are duplicated menu items in the action bar.
An important detail is that the only duplicated items are those that are created in the onCreateOptionsMenu() of each fragment I use in the ViewPager.
If I replaceFragmentStatePageAdapter with FragmentPageAdapter the items are not duplicated anymore, but the fragments are not shown in the ViewPager (getItem() function from the adapter is never called so it does not return any fragment).
Any ideas? A way to avoid FragmentStatePageAdapter to duplicate menu items? Maybe use FragmentPageAdapter but with a modification to show the fragments? A modification in my fragments?
Here are some code snippets from my application...
How menu items are created inside the fragments:
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
/* Create play button */
final MenuItem mPlay = menu.add(R.string.play_all);
mPlay.setIcon(R.drawable.ic_play_all);
mPlay.setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);
mPlay.setOnMenuItemClickListener(new OnMenuItemClickListener() {
#Override
public boolean onMenuItemClick(MenuItem item) {
final List<Song> songs = getSongs();
if (songs.size() == 0) {
/* Show message */
Toast.makeText(mContext, R.string.no_song_list, Toast.LENGTH_LONG).show();
} else {
/* Play song list */
try { PlayManager.getService().playList(songs); } catch (Exception e) {}
}
return false;
}
});
/* Create menu */
super.onCreateOptionsMenu(menu, inflater);
}
How fragments are instantiated in the ViewPager adapter
#Override
public Fragment getItem(int position) {
final Class<?> cls = mTabs.get(position);
/* No tab */
if (cls == null)
return null;
/* Instantiate fragment */
final Fragment fragment = Fragment.instantiate(mContext, cls.getName(), null);
/* Add to list */
mFragments.put(position, fragment);
/* Return fragment */
return fragment;
}
Thanks!
PS: I tried to change the launchMode of the activity to "singleTop" and I also tried to return in getItem() the previosly created fragment (but that's useless as getItem() is never called when I return to the application, as I said before).
I found a solution to my problem a few days after posting my problem. I'm sorry for putting it here so late.
The following code fixed my problem:
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.remove("android:support:fragments");
}
As simple as writing that piece of code in the activity where I instantiate and use the fragments.
I hope this helps :)
Before inflating the options menu in your Fragment inside the ViewPager, check whether the Fragment instance is visible to prevent duplicated menu items:
// This should be in your Fragment implementation
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
{
if(isVisible())
{
inflater.inflate(R.menu.menu_fragment, menu);
}
super.onCreateOptionsMenu(menu, inflater);
}
I assume the problem is that the FragmentStatePagerAdapter creates a new Fragment each time you swipe. As a result, onCreateOptionsMenu() is called for each Fragment that is created.
There are, I think, two solutions:
Take the action bar manipulation out of the Fragments. Instead of setting an onclick for the menu item inside of the Fragment, you send a message to the current Fragment from the Activity.
Use Menu.findItem() to see if another Fragment has already added the MenuItem you want, and if so attach the current Fragment to it (in onPrepareOptionsMenu()).
I found some solution try it may be work
In your duplicate menu fragment
Add menu.clear() before inflate menu file in onCreateOptionsMenu(Menu menu, MenuInflater inflater)
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
menu.clear();
inflater.inflate(R.menu.main,menu);
}