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Fragment activity disappears after switching activities

I have 6 fragments fragments for my navigation drawer, one of which contains 2 other fragments which i use for a viewPager. My problem is that when i switch from the fragment containing the viewPager(HomeFragment) to another and switch back, the contents of both Fragments in HomeFragment disappears.
Here's my code
MainActivity.class
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
...
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new HomeFragment()).commit();
navigationView.setCheckedItem(R.id.nav_home);
...
}
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.nav_home:
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new HomeFragment()).commit();
toolbar.setTitle("mSeries");
toolbar.setTitleTextColor(getResources().getColor(R.color.colorPrimaryDark));
break;
...
HomeFragment.class
public class HomeFragment extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_home, container, false);
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
ViewPager viewPager = view.findViewById(R.id.viewpager);
setupViewPager(viewPager);
TabLayout tabLayout = view.findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getFragmentManager());
adapter.addFragment(new UpcomingShowsActivity(), "Upcoming episodes");
adapter.addFragment(new UnwatchedEpisodesActivity(), "Unwatched episodes");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#NonNull
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
}
UpcomingShowsActivity.class
public class UpcomingShowsActivity extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_upcoming_episodes, container, false);
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
}
I am a newbie in android, if there's a better or more efficient way of achieving this please let me know.
Thanks for your time.

I fixed it myself and I'm posting this in case someone has a similar issue in the future
Because I'm making a fragment in another fragment, I am supposed to use getChildFragmentManager instead of get getFragmentManager in my HomeFragment.class
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getChildFragmentManager());
adapter.addFragment(new UpcomingShowsActivity(), "Upcoming episodes");
adapter.addFragment(new UnwatchedEpisodesActivity(), "Unwatched episodes");
viewPager.setAdapter(adapter);
}

Reload Fragment, Fragment dont call onCreateView

i have a Fragment(C) with a ViewPager(Adapter) with 2 Fragments(A/B).
When i call the Fragment once time, they load fine.
But when i call the Fragment(C) the secend time, the Fragment A and B dont call the View onCreateView methode and the isn´t loaded.
The Fragment C is called with Fragmetnmanger:
FragmentC fragment = new FragmentC();
getActivity().getSupportFragmentManager().beginTransaction().replace(R.id.adressenmdf_detail_container, fragment).addToBackStack(null).commit();
Fragment C
public BelegeDetails(){
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.activity_belege_details, container, false);
//TODO Actionbar noch anpassen
//getSupportActionBar().setDisplayHomeAsUpEnabled(true);
viewPager = (ViewPager) rootView.findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) rootView.findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
setupTabIcons();
The Setups from Fragment C
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(this.getFragmentManager());
adapter.addFragment(new BelegeDetails1(),"Details" );
adapter.addFragment(new BelegeDetailsPos(), "Positionen");
viewPager.setAdapter(adapter);
}
private void setupTabIcons() {
tabLayout.getTabAt(1).setIcon(R.drawable.ic_belege);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
The Fragment A BelegDetails1 und the Fragment B BelegDetailsPos are normal Fragment Classes like:
public BelegeDetails1() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState.......

try changing this:
ViewPagerAdapter adapter = new ViewPagerAdapter(this.getFragmentManager());
with:
ViewPagerAdapter adapter = new ViewPagerAdapter(getChildFragmentManager());
As you are nesting fragments, you need to use getChildFragmentManager() instead of getFragmentManager()

OnClick Fragment to Fragment switch results in Blank Screen

When switching from one fragment to another fragment (within the second tab of my application), my second fragment is blank. I have tried the solutions linked here, but none seem to work:
Transaction of fragments in android results in blank screen
Android: Getting white screen with fragment transaction
MainActivity:
public class MainActivity extends AppCompatActivity {
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_activity);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
// Set up the ViewPager with the sections adapter, and add pages.
mViewPager = (ViewPager) findViewById(R.id.container);
mSectionsPagerAdapter.addPage(new Received());
mSectionsPagerAdapter.addPage(new Send());
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_alert_partners, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if(getArguments().getInt(ARG_SECTION_NUMBER)==1) {
View rootView = inflater.inflate(R.layout.fragment_received, container, false);
return rootView;
}
else if(getArguments().getInt(ARG_SECTION_NUMBER)==2) {
View rootView = inflater.inflate(R.layout.fragment_send, container, false);
return rootView;
}
else {//main empty fragment in case of error. Never used in normal behaviour.
View rootView = inflater.inflate(R.layout.fragment_alert_partners, container, false);
return rootView;
}
}
}
public class SectionsPagerAdapter extends FragmentPagerAdapter {
//Create an Array list that will hold the pages.
ArrayList<Fragment> pages = new ArrayList<>();
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
return pages.get(position);
}
//Add a page
public void addPage(Fragment f) {
pages.add(f);
}
#Override
public int getCount() {
// Show 2 total pages.
return 2;
}
#Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "Received";
case 1:
return "Send";
}
return null;
}
}
}
SendFragment:
public class Send extends Fragment {
private OnFragmentInteractionListener mListener;
private TextView text1;
public Send() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.fragment_send, container, false);
//Need getView() for fragment since setContentView must be set first but is not possible in fragment.
text1 = (TextView)v.findViewById(R.id.textview1);
text1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
Send2 send2 = new Send2();
fragmentTransaction.addToBackStack(null);
fragmentTransaction.hide(Send.this);
fragmentTransaction.add(android.R.id.content, send2);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();
}
});
return v;
}
public interface OnFragmentInteractionListener {
}
}
Send2Fragment:
public class Send2 extends Fragment {
private OnFragmentInteractionListener mListener;
public Send2() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
final View v = inflater.inflate(R.layout.fragment_send2, container, false);
return v;
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
}
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnFragmentInteractionListener {
}
}

Had to add a framelayout at the end of the layout code for the fragment I was replacing:
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/send1frameLayoutId">
</FrameLayout>
Then used this code to switch to a fragment in the same tab of the previous fragment:
Fragment send2 = new Send2();
FragmentManager fragmentManager = getChildFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.send1frameLayoutId, send2);
fragmentTransaction.addToBackStack(null);
fragmentTransaction.commit();

How to notify an Adapter in a Fragment from Activity?

I have a TabLayout in mainActivity with some tabs, tabs are Fragments.
And on each Fragment I have a ReclerView.
From the main Activity I want to call notifyDatasetChange() on my Adapter in my Fragment for updating the UI.
But how to notify it?
myMainActivity:
final ViewPager viewPager = (ViewPager) findViewById(R.id.viewPager);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabLayout);
tabLayout.addTab(tabLayout.newTab().setText("Tab1"));
tabLayout.addTab(tabLayout.newTab().setText("Tab2"));
final PagerAdapter adapter = new PagerAdapter
(getSupportFragmentManager(), tabLayout.getTabCount());
viewPager.setAdapter(adapter);
viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
#Override
public void onTabSelected(TabLayout.Tab tab) {
viewPager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(TabLayout.Tab tab) {
}
#Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
One of myTabFragment:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
RecyclerView v = (RecyclerView) inflater.inflate(R.layout.tab_fragment_1, container, false);
SetupRecycleView(v);
return v;
}
void SetupRecycleView(RecyclerView recList) {
recList.setHasFixedSize(true);
LinearLayoutManager llm = new LinearLayoutManager(G.context);
llm.setOrientation(LinearLayoutManager.VERTICAL);
//recList.setLayoutManager(new GridLayoutManager(G.context, 2));
recList.setLayoutManager(llm);
List<StructGhaza> ghazas = StructGhaza.getAllGhaza("2");
CardAdapter adapter = new CardAdapter(ghazas);
recList.setAdapter(adapter);
}
The CardAdapter:
public class CardAdapter extends RecyclerView.Adapter<CardAdapter.GhazaViewHolder> {
private List<StructGhaza> ghazas;
public CardAdapter(List<StructGhaza> ghazaList) {
this.ghazas = ghazaList;
}
#Override
public int getItemCount() {
return ghazas.size();
}
#Override
public void onBindViewHolder(GhazaViewHolder ghazaViewHolder, int position) {
StructGhaza ghaza = ghazas.get(position);
ghazaViewHolder.vTitle.setText(ghaza.Name);
//----Load Image
Glide.with(G.context)
.load(ghaza.Aks)
.placeholder(R.drawable.loading_spinner)
.crossFade()
.into(ghazaViewHolder.itemImg);
//---------------
ghazaViewHolder.Rate.setRating(ghaza.Star);
ghazaViewHolder.sampleLayout.setHoverView(ghazaViewHolder.hover);
ghazaViewHolder.sampleLayout.addChildAppearAnimator(ghazaViewHolder.hover, R.id.tvHover, Techniques.FlipInX);
ghazaViewHolder.sampleLayout.addChildDisappearAnimator(ghazaViewHolder.hover, R.id.tvHover, Techniques.FlipOutX);
}
#Override
public GhazaViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View itemView = LayoutInflater.
from(viewGroup.getContext()).
inflate(R.layout.fragment_carditem, viewGroup, false);
return new GhazaViewHolder(itemView);
}
public static class GhazaViewHolder extends RecyclerView.ViewHolder {
protected TextView vTitle;
protected BlurLayout sampleLayout;
protected View hover;
protected ImageView itemImg;
protected RatingBar Rate;
public GhazaViewHolder(View v) {
super(v);
sampleLayout = (BlurLayout) v.findViewById(R.id.sample);
itemImg = (ImageView) v.findViewById(R.id.item_img);
hover = LayoutInflater.from(G.context).inflate(R.layout.fragment_hover, null);
vTitle = (TextView) v.findViewById(R.id.titleTv);
Rate = (RatingBar) v.findViewById(R.id.rating);
}
}
}

I would recommend putting a public method in your Fragment and then calling from the Activity. See "Deliver a Message to a Fragment" here:
http://developer.android.com/training/basics/fragments/communicating.html
In your Activity, just do the following to make sure the Fragment method can be called:
TabFragment tabFragment = (TabFragment) getSupportFragmentManager().findFragmentByTag(TAB_FRAGMENT_TAG);
// Check if the tab fragment is available
if (tabFragment != null) {
// Call your method in the TabFragment
articleFrag.yourMethod();
}
And then in the Fragment, have the following method:
public void yourMethod() {
recyclerViewAdapter.notifyDataSetChanged();
}

you create updateListview() in your fragment like
public void updateListView() {
yourAdapter.notifyDataSetChanged();
}
and updateListview() in your Activity like
updateListView();

Add fragment into viewPager's fragment

I have viewpager with 3 fragments (same layout - some EditText and Buttons) and I want to dynamically add small fragment above the viewpager fragment, write something in and then hide it.
This is what I tried:
MainActivity.java:
public class MainActivity extends FragmentActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ViewPager pager = (ViewPager) findViewById(R.id.viewPager);
pager.setAdapter(new MyPagerAdapter(getSupportFragmentManager()));
}
private class MyPagerAdapter extends FragmentPagerAdapter {
public MyPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int pos) {
switch(pos) {
case 0: return MainFragment.newInstance("1");
case 1: return MainFragment.newInstance("2");
case 2: return MainFragment.newInstance("3");
default: return MainFragment.newInstance("");
}
}
#Override
public int getCount() {
return 3;
}
}
}
MainFragment.java:
public class MainFragment extends android.support.v4.app.Fragment {
EditText contentEdit;
String content, ID;
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ID = getArguments().getString("msg");
}
#Override
public View onCreateView(LayoutInflater inflater, final ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_main, container, false);
contentEdit = (EditText) view.findViewById(R.id.editText);
contentEdit.setOnTouchListener(new OnSwipeTouchListener(getActivity()) {
public void onSwipeBottom() {
final ViewGroup newView = (ViewGroup) LayoutInflater.from(getActivity()).inflate(R.layout.fragment_title, container, false);
newView.findViewById(R.id.delete_button).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
container.removeView(newView);
}
});
container.addView(newView, 0);
}
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
});
return view;
}
}

Try to put a frame layout above that viewPager layout BUT set it's visibility to GONE therefore it won't "exist". Now in your pager onItemClick listener for that small fragment you want to show call findViewByID(R.id.YourFrameLayout).setVisibility(View.VISIBLE); and when you want to hide it, well you get the idea. Don't forget to add your fragment to that container, e.g. YourFrameLayout