Develop Reference

How to replace the first Fragment of ViewPager with another Fragment and be at the same position of the previous Fragment

I'm using TabLayout and ViewPager in my app . I have 2 tabs in my ViewPager . I have the main 2 Fragment for the 2 tabs .
The first Fragment is like a form when user click submit , another Fragment appears to user and so on and be at the same position of the previous Fragment. I want to do that in the first Fragment (first position of my ViewPager) and keep the state of the previous fragment when I click back button . I hope that I posted my question in a right way
Here is my ViewPager
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
tools:context=".UI.Fragments.OnlineBookingModule.OnlineBookingFragment">
<com.google.android.material.tabs.TabLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/tabLayout"
app:tabIndicatorColor="#color/colorPrimary"
android:background="#color/bg_nav"/>
<androidx.viewpager.widget.ViewPager
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/viewPager"/>
</LinearLayout>
Here is My Pager Adapter
public class BookingPagerAdapter extends FragmentStatePagerAdapter {
private Context context;
public BookingPagerAdapter(#NonNull FragmentManager fm, int behavior,Context context) {
super(fm, behavior);
this.context=context;
}
#NonNull
#Override
public Fragment getItem(int position) {
if(position==0)
return new NewBookingFragment();
else
return new FutureBookingFragment();
}
#Override
public int getCount() {
return 2;
}
#Nullable
#Override
public CharSequence getPageTitle(int position) {
if(position==0)
return context.getString(R.string.new_booking);
else
return context.getString(R.string.future_booking);
}
}
Here is how I setup my viewPager in my Fragment
#RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR1)
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_online_booking, container, false);
tabLayout = view.findViewById(R.id.tabLayout);
viewPager = view.findViewById(R.id.viewPager);
Preferences preferences = new Preferences();
preferences.saveSmallDays(getActivity(),0);
preferences.saveBigDays(getActivity(),0);
assert getFragmentManager() != null;
pagerAdapter = new BookingPagerAdapter(getFragmentManager(), FragmentStatePagerAdapter.BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT,getActivity());
tabLayout.setupWithViewPager(viewPager);
viewPager.setAdapter(pagerAdapter);
return view;
}

Replace fragment in fragment itself in TabActivity

I am sorry on the duplicate question but I didn't get answer for my problem.
I create app with TabActivity and also trying to replace one fragment from fragment itself, I read in https://developer.android.com/training/basics/fragments/fragment-ui.html how to do it and i created interface in my fragment that i want to be replace with another,
I implement the interface in my MainActivity and still when running my app it show me container itself.
here is my code:
Main Activity:
public class MainActivity extends FragmentActivity implements New2.OnReplaceFragment {
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
public static MainActivity instance = null;
public static MainActivity getInstance(){
return instance;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
mViewPager = (ViewPager) findViewById(R.id.frame_container);
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
tabLayout.getTabAt(0).setIcon(R.drawable.icon_info);
tabLayout.getTabAt(1).setIcon(R.drawable.icon_heart_rate_sensor_jpg);
tabLayout.getTabAt(2).setIcon(R.drawable.icon_graph_jpg);
instance = this;
}
#Override
public void onReplaceFragment(Class fragmentClass) {
Fragment fragment = null;
try {
fragment = (Fragment) fragmentClass.newInstance();
} catch (Exception e) {
e.printStackTrace();
}
// Insert the fragment by replacing any existing fragment
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.frame_container,fragment);
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack so the user can navigate back
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
}
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) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
TextView textView = (TextView) rootView.findViewById(R.id.section_label);
textView.setText(getString(R.string.section_format, getArguments().getInt(ARG_SECTION_NUMBER)));
return rootView;
}
}
public class SectionsPagerAdapter extends FragmentPagerAdapter {
public SectionsPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
// getItem is called to instantiate the fragment for the given page.
// Return a PlaceholderFragment (defined as a static inner class below).
switch (position) {
case 0:
// New1 tab1 = new New1();
return New1.newInstance();
case 1:
return New2.newInstance();
case 2:
return New3.newInstance();
default:
return null;
}
}
#Override
public int getCount() {
// Show 3 total pages.
return 3;
}
#Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return "SECTION 1";
case 1:
return "SECTION 2";
case 2:
return "SECTION 3";
}
return null;
}
}
}
my fragment that I want to replace
Fragment:
public class New2 extends Fragment {
TextView name;
Button change;
ImageView image1;
Animation anime;
private OnReplaceFragment dataPasser;
public static New2 newInstance(){
New2 fragment = new New2();
return fragment;
}
public New2(){
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_new2, container, false);
name = (TextView) rootView.findViewById(R.id.nameTt);
change = (Button) rootView.findViewById(R.id.changeBtn);
image1 = (ImageView) rootView.findViewById(R.id.image1);
anime = AnimationUtils.loadAnimation(getActivity().getApplicationContext(),R.anim.zoom);
change.setOnClickListener(changeName);
return rootView;
}
View.OnClickListener changeName = new View.OnClickListener() {
#Override
public void onClick(View view) {
image1.startAnimation(anime);
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run(){
dataPasser.onReplaceFragment(Result.class);
}
},1000);
}
};
public interface OnReplaceFragment {
public void onReplaceFragment(Class fragmentClass);
}
#Override
public void onAttach(Activity a) {
super.onAttach(a);
try {
dataPasser = (OnReplaceFragment) a;
} catch (ClassCastException e) {
throw new ClassCastException(a.toString() + " must implement onDataPass");
}
}
}
the fragment that i want to display
public class Result extends Fragment {
TextView textView;
Button btnBack;
public static Result instance = null;
public static Result getInstance(){
return instance;
}
public Result() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.fragment_result, container, false);
textView = (TextView) v.findViewById(R.id.text11);
btnBack = (Button) v.findViewById(R.id.btnBack);
textView.setText("working!!");
Toast.makeText(getActivity().getApplicationContext(),"working",Toast.LENGTH_LONG).show();
return v;
}
}
Main Activity XML:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.example.hercules.tadhosttutrial.MainActivity">
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="#dimen/appbar_padding_top"
android:background="#color/red"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
New2 XML:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.hercules.tadhosttutrial.New2"
android:background="#color/yellow">
<!-- TODO: Update blank fragment layout -->
<Button
android:id="#+id/changeBtn"
android:layout_width="80dp"
android:layout_height="40dp"
android:layout_gravity="center_horizontal"
android:text="change"/>
<ImageView
android:id="#+id/image1"
android:background="#drawable/icon_complete"
android:layout_width="200dp"
android:layout_height="200dp"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
/>
Result XML:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/colorAccent"
tools:context="com.example.hercules.tadhosttutrial.Result">
<!-- TODO: Update blank fragment layout -->
<Button
android:id="#+id/btnBack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="back"/>
<TextView
android:id="#+id/text11"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="WORKING"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:textSize="70dp"
/>
</RelativeLayout>

What i mean, is making MainActivity as a main container for all fragments, either with tabs or just a regular fragment,
1- Main Activity XML: remove ViewPager, add a FrameLayout instead (use same id)
2- Create new fragment TabsFragment with this XML:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.hercules.tadhosttutrial.New2"
android:background="#color/yellow">
<android.support.v4.view.ViewPager
android:id="#+id/frame_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</RelativeLayout>
3- Move initializing SectionsPagerAdapter and ViewPager from main activity to TabsFragment:
this part:
private SectionsPagerAdapter mSectionsPagerAdapter;
private ViewPager mViewPager;
and this:
mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
mViewPager = (ViewPager) findViewById(R.id.frame_container);
mViewPager.setAdapter(mSectionsPagerAdapter);
TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
tabLayout.setupWithViewPager(mViewPager);
tabLayout.getTabAt(0).setIcon(R.drawable.icon_info);
tabLayout.getTabAt(1).setIcon(R.drawable.icon_heart_rate_sensor_jpg);
tabLayout.getTabAt(2).setIcon(R.drawable.icon_graph_jpg);
4- I think moving SectionsPagerAdapter class in a new file is better too.
now if you want default view for app to be the tabs, then in MainActivity at onCreate() show TabsFragment by calling your method:
onReplaceFragment(TabsFragment.class);
now every thing should work fine, because the idea here is to replace the fragment displayed in main activity with another one
in this case TabsFragment, Result, and New2
not to replace viewpager fragments (because as i told you this is managed via the adapter) not by calling replace()
you may need to play around this, it's not a final code, just something to give you idea about it.

Title strip not scrolling to next tab automatically instead moving as per the movement of the swipe gesture

Title strip which indicates the selected tab does not automatically move to the next tab on one swipe. It moves accordingly to the swipe gesture for instance if you swipe just a little strip will move just a little even if it indicating the same tab.
I want to implement tab layout in fragment as user will be navigating on this page from navigation drawer.
Xml code
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.TabLayout
android:id="#+id/aboutTabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="fixed"
app:tabGravity="fill"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/aboutViewPager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
code hosting the xml
public class AboutFragment extends Fragment{
#BindView(R.id.aboutTabs)
public TabLayout tabLayout;
#BindView(R.id.aboutViewPager)
public ViewPager viewPager;
private View rootView;
/**
* Mandatory empty constructor for the fragment manager to instantiate the
* fragment (e.g. upon screen orientation changes).
*/
public AboutFragment() {
}
public static Fragment newInstance() {
Fragment fragment = new AboutFragment();
return fragment;
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
rootView = inflater.inflate(R.layout.fragment_about, container, false);
ButterKnife.bind(this, rootView);
setupViewPager(viewPager);
tabLayout.setupWithViewPager(viewPager);
return rootView;
}
private void setupViewPager(ViewPager viewPager) {
AboutPagerAdapter adapter = new AboutPagerAdapter(getChildFragmentManager());
adapter.addFragment(new AboutUsFragment(), getResources().getString(R.string.str_about_us));
adapter.addFragment(new MissionFragment(), getResources().getString(R.string.str_about_mission));
adapter.addFragment(new ValuesFragment(), getResources().getString(R.string.str_about_values));
viewPager.setAdapter(adapter);
}
}
adapter
public class AboutPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public AboutPagerAdapter(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
What is causing this issue? Where I am making mistake?
Thanks in advance

If the fragments are empty this behaviour is observed. So just add your layouts in the respective fragments and it will resolve the issue.

TabLayout - ViewPager - Fragment

I have a problem with my ViewPager and fragments it contains. I have 2 menus (A and B), my homepage is directly A. When I click on a menu B fragment which contains a TabLayout, which contains a ViewPager himself three fragments (each contains a simple TextView with Lorem ipsum).
The 3 fragments of ViewPager are correct but if I click on the menu A and I click again on the menu B I do not have any content. Nothing on the fragments 1 and 2 against with the 3rd still has the text and if I return to fragment 1 reads income (for nothing against the fragment 2).
Here is my code :
Menu B (FragmentTabLayout)
public class TabLayoutFragment extends Fragment {
private static final String ARG_TEXT = "ARG_TEXT";
private static final String ARG_COLOR = "ARG_COLOR";
private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;
public TabLayoutFragment() {
// Required empty public constructor
}
public static TabLayoutFragment newInstance(String text, int color) {
Bundle args = new Bundle();
args.putString(ARG_TEXT, text);
args.putInt(ARG_COLOR, color);
TabLayoutFragment tabLayoutFragment = new TabLayoutFragment();
tabLayoutFragment.setArguments(args);
return tabLayoutFragment;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
setHasOptionsMenu(true);
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_tab_layout, container, false);
toolbar = (Toolbar) view.findViewById(R.id.toolbar);
((AppCompatActivity)getActivity()).setSupportActionBar(toolbar);
toolbar.setBackgroundColor(getArguments().getInt(ARG_COLOR));
toolbar.setTitle(getArguments().getString(ARG_TEXT));
viewPager = (ViewPager) view.findViewById(R.id.viewpager);
setupViewPager(viewPager);
tabLayout = (TabLayout) view.findViewById(R.id.tabs);
tabLayout.setupWithViewPager(viewPager);
tabLayout.setBackgroundColor(getArguments().getInt(ARG_COLOR));
tabLayout.setSelectedTabIndicatorColor(Color.WHITE);
return view;
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.tab_menu, menu);
super.onCreateOptionsMenu(menu, inflater);
}
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getActivity().getSupportFragmentManager());
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
//private final List<TabFragment> mFragmentList = new ArrayList<>();
//private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return TabFragment.newInstance("Fragment 2-1");
case 1:
return TabFragment.newInstance("Fragment 2-2");
case 2:
return TabFragment.newInstance("Fragment 2-3");
default:
return TabFragment.newInstance("Fragment Default");
}
}
#Override
public int getCount() {
//return mFragmentList.size();
return 3;
}
}
}
Fragment in ViewPager :
public class TabFragment extends Fragment {
private static final String ARG_TEXT = "ARG_TEXT";
private TextView tv;
public TabFragment() {
// Required empty public constructor
}
public static TabFragment newInstance(String text) {
Bundle args = new Bundle();
args.putString(ARG_TEXT, text);
TabFragment tabFragment= new TabFragment();
tabFragment.setArguments(args);
return tabFragment;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_tab, container, false);
tv = (TextView) view.findViewById(R.id.tv);
return view;
}
}
Layout FragmentTabLayout :
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light" />
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="fixed"
app:tabGravity="fill"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</android.support.design.widget.CoordinatorLayout>
layout tabFragment :
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
tools:context="com.application.myapplication.TabFragment">
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
>
<TextView
android:id="#+id/tv"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="#string/lorem_ipsum"
/>
</android.support.v4.widget.NestedScrollView>
</LinearLayout>

you can extends your ViewPagerAdapter
FragmentStatePagerAdapter
instead of
FragmentPagerAdapter
I have same issue and it works for me.

In my Opinion the better approach is you should try using childFragmentManager for your nested fragments
Here is the simple example:
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getActivity().getChildFragmentManager());
viewPager.setAdapter(adapter);
}
Hopefully it will solve your issue.

Android: TabLayout not showing any tabs

First time working with com.android.support:design:23.1.1, and having some issues getting TabLayout to work.
My app is basically set up as such:
One main activity called LandingActivity which has a DrawerLayout with menu items in it.
When selecting a menu item, I load different Fragments into a FrameLayout in the LandingActivity.
Some of the loaded Fragments should show tabs at the top, some shouldn't.
My issue is, on the Fragment which is supposed to show tabs at the top, it has extra space in the nav bar like it should have tabs there, but nothing shows.
Code:
activity_landing.xml
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- This LinearLayout represents the contents of the screen -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<!-- The ActionBar displayed at the top -->
<include
layout="#layout/tool_bar"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<!-- The main content view where fragments are loaded -->
<FrameLayout
android:id="#+id/flContent"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
<!-- The navigation drawer that comes from the left -->
<!-- Note that `android:layout_gravity` needs to be set to 'start' -->
<android.support.design.widget.NavigationView
android:id="#+id/nvView"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="#android:color/white"
app:menu="#menu/drawer" />
LandingActivity where I load the fragments:
public void selectDrawerItem(MenuItem menuItem) {
// Create a new fragment and specify the planet to show based on
// position
Fragment fragment = null;
switch(menuItem.getItemId()) {
case R.id.drawer_home:
fragment = HomeFragment.newInstance();
break;
case R.id.drawer_customize:
fragment = CustomizeFragment.newInstance();
break;
default:
fragment = HomeFragment.newInstance();
}
// Insert the fragment by replacing any existing fragment
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction().replace(R.id.flContent, fragment).commit();
home_fragment.xml (one which has tabs)
<android.support.design.widget.AppBarLayout 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:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.TabLayout
android:id="#+id/tabLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="fixed"
app:tabGravity="fill"
/>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#android:color/white"/>
HomeFragment.java
public class HomeFragment extends Fragment {
public static HomeFragment newInstance() {
Bundle args = new Bundle(); alreadySelectedFollowingInfo);
HomeFragment fragment = new HomeFragment();
fragment.setArguments(args);
return fragment;
}
public HomeFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View v = inflater.inflate(R.layout.fragment_home, container, false);
final TabLayout tabLayout = (TabLayout) v.findViewById(R.id.tabLayout);
tabLayout.addTab(tabLayout.newTab().setText("One"));
tabLayout.addTab(tabLayout.newTab().setText("Two"));
final ViewPager viewPager = (ViewPager) v.findViewById(R.id.viewpager);
viewPager.setAdapter(new PagerAdapter
(getFragmentManager(), tabLayout.getTabCount()));
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) {
}
});
tabLayout.post(new Runnable() {
#Override
public void run() {
tabLayout.setupWithViewPager(viewPager);
}
});
return inflater.inflate(R.layout.fragment_home, container, false);
}
public class PagerAdapter extends FragmentStatePagerAdapter {
int mNumOfTabs;
public PagerAdapter(FragmentManager fm, int NumOfTabs) {
super(fm);
this.mNumOfTabs = NumOfTabs;
}
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
BlogFragment tab1 = BlogFragment.newInstance();
return tab1;
case 1:
TrendingFragment tab2 = TrendingFragment.newInstance();
return tab2;
default:
return null;
}
}
#Override
public int getCount() {
return mNumOfTabs;
}
}
}
Might not be relevant, but tool_bar.xml used in activity_landing.xml
<android.support.v7.widget.Toolbar
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/toolbar"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:fitsSystemWindows="true"
android:minHeight="?attr/actionBarSize"
app:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
android:background="?attr/colorPrimary">
That's about all I've got. Can't figure out what's going on.
EDIT:
New code:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View v = inflater.inflate(R.layout.fragment_home, container, false);
ViewPager viewPager = (ViewPager) v.findViewById(R.id.viewpager);
setupViewPager(viewPager);
TabLayout tabLayout = (TabLayout) v.findViewById(R.id.tabLayout);
tabLayout.setupWithViewPager(viewPager);
return v;
}
private void setupViewPager(ViewPager viewPager) {
PagerAdapter adapter = new PagerAdapter(getFragmentManager());
adapter.addFragment(BlogFragment.newInstance(), "ONE");
adapter.addFragment(TrendingFragment.newInstance(), "TWO");
viewPager.setAdapter(adapter);
}
class PagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public PagerAdapter(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);
}
}

return inflater.inflate(R.layout.fragment_home, container, false);
in your onCreateView means that you return a newly inflated home fragment without any of your initialization code.
You should be returning the view that you created at the beginning of onCreateView:
return v;
Sample PagerAdapter that provides tab titles:
public class PagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragments = new ArrayList<>();
private final List<String> mFragmentTitles = new ArrayList<>();
public PagerAdapter(FragmentManager fm) {
super(fm);
}
public void addFragment(Fragment fragment, String title) {
mFragments.add(fragment);
mFragmentTitles.add(title);
}
#Override
public Fragment getItem(int position) {
return mFragments.get(position);
}
#Override
public int getCount() {
return mFragments.size();
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitles.get(position);
}
}
And so, your refactored onCreateView code would be something like:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_home, container, false);
final TabLayout tabLayout = (TabLayout) v.findViewById(R.id.tabLayout);
final ViewPager viewPager = (ViewPager) v.findViewById(R.id.viewpager);
PagerAdapter adapter = new PagerAdapter(getFragmentManager());
adapter.addFragment(BlogFragment.newInstance(), "One");
adapter.addFragment(TrendingFragment.newInstance(), "Two");
viewPager.setAdapter(adapter);
tabLayout.post(new Runnable() {
#Override
public void run() {
tabLayout.setupWithViewPager(viewPager);
}
});
return v;
}

Return your initialized infleted view while you are returning
return inflater.inflate(R.layout.fragment_home, container, false);
while you should return view v from first line of onCreateView
final View v = inflater.inflate(R.layout.fragment_home, container, false);