opening and navigating between fragments in viewpager

Question

I've a FrameLayout and Navigation Drawer in Main Activity. I'm transacting a fragment in Main Activity using this FrameLayout. In this fragment, I've TabLayout and ViewPager. Now what I want is to open a new fragment on Button click in the ViewPager fragment. But app crashes on Button click. Is it becuz FrameLayout is in Main Activity and the Button is in child fragment's child fragment? I've tried using FrameLayout in Tabs but that would mean I would have to use FrameLayouts for each Tab and I don't want that. So any help in this regard will be much appreciated. Also, how to handle back arrow click in toolbar to go back to previous fragment?

 public class HomeFragment extends Fragment { public static TabLayout tabLayout; public static ViewPager viewPager; public static int int_items = 2; @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { return inflater.inflate(R.layout.homefragment, container, false); } @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); tabLayout = (TabLayout) view.findViewById(R.id.tabs); viewPager = (ViewPager) view.findViewById(R.id.viewpager); viewPager.setAdapter(new MyAdapter(getChildFragmentManager())); tabLayout.post(new Runnable() { @Override public void run() { tabLayout.setupWithViewPager(viewPager); } }); } class MyAdapter extends FragmentPagerAdapter { public MyAdapter(FragmentManager fm) { super(fm); } /** * Return fragment with respect to Position . */ @Override public Fragment getItem(int position) { switch (position){ case 0 : return new TabOne(); case 1 : return new TabTwo(); } return null; } @Override public int getCount() { return int_items; } /** * This method returns the title of the tab according to the position. */ @Override public CharSequence getPageTitle(int position) { switch (position){ case 0 : return "ONE"; case 1 : return "TWO"; } return null; } } } 

 public class TabOne extends Fragment { private Button newFrag; @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { return inflater.inflate(R.layout.tabone, container, false); } @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); newFrag = (Button)view.findViewById(R.id.button); newFrag.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { FragmentTransaction xfragmentTransaction = getChildFragmentManager().beginTransaction(); xfragmentTransaction.replace(R.id.containerView, new NewFrag()).addToBackStack(null).commit(); } }); } } 

 public class MainActivity extends AppCompatActivity { DrawerLayout myDrawerLayout; NavigationView myNavigationView; Toolbar toolbar; ActionBarDrawerToggle mDrawerToggle; FragmentManager myFragmentManager; FragmentTransaction myFragmentTransaction; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); myDrawerLayout = (DrawerLayout) findViewById(R.id.drawerLayout); myNavigationView = (NavigationView) findViewById(R.id.nav_drawer) ; myFragmentManager = getSupportFragmentManager(); myFragmentTransaction = myFragmentManager.beginTransaction(); myFragmentTransaction.replace(R.id.containerView, new HomeFragment()).commit(); myNavigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() { @Override public boolean onNavigationItemSelected(MenuItem selectedMenuItem) { myDrawerLayout.closeDrawers(); if (selectedMenuItem.getItemId() == R.id.nav_profile) { FragmentTransaction fragmentTransaction = myFragmentManager.beginTransaction(); fragmentTransaction.replace(R.id.containerView, new ProfileFragment()).addToBackStack(null).commit(); } if (selectedMenuItem.getItemId() == R.id.nav_history) { FragmentTransaction xfragmentTransaction = myFragmentManager.beginTransaction(); xfragmentTransaction.replace(R.id.containerView, new HistoryFragment()).addToBackStack(null).commit(); } return false; } }); toolbar = (Toolbar)findViewById(R.id.toolbar); mDrawerToggle = new ActionBarDrawerToggle(this, myDrawerLayout, toolbar, R.string.app_name, R.string.app_name); myDrawerLayout.setDrawerListener(mDrawerToggle); mDrawerToggle.syncState(); } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case android.R.id.home: onBackPressed(); break; default: break; } return super.onOptionsItemSelected(item); } } 

 FATAL EXCEPTION: main Process: com.sam.demonavigation, PID: 8523 java.lang.IllegalArgumentException: No view found for id 0x7f0c006b (com.sam.demonavigation:id/containerView) for fragment HistoryFragment{42016928 #0 id=0x7f0c006b} at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1059) at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1252) at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:742) at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1617) at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:517) at android.os.Handler.handleCallback(Handler.java:808) at android.os.Handler.dispatchMessage(Handler.java:103) at android.os.Looper.loop(Looper.java:193) at android.app.ActivityThread.main(ActivityThread.java:5388) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:515) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:655) at dalvik.system.NativeStart.main(Native Method) 

Answer 1

This link proved to be very useful. Using the method mentioned in my link I was able to use the FrameLayout in my Main Activity to open any fragment

 // This is the button click event in one of the TabLayout fragment newFrag.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Fragment var1 = new NewFrag(); ((MainActivity)getActivity()).replaceFragment(var1); } }); 

 // Add this method in MainActivity public void replaceFragment(Fragment fragment){ FragmentTransaction t = getSupportFragmentManager().beginTransaction(); t.replace(R.id.containerView, fragment).addToBackStack(null); t.commit(); } 

.

Answer 2

1-Create ViewPager object

      ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
            viewPager.setOffscreenPageLimit(3);
            setupViewPager(viewPager);

2-then add Custom FragmentPagerAdapter

 ViewPagerAdapter adapter = new ViewPagerAdapter(this);
 adapter.addFrag(new Fragment1(), "Item1");
 adapter.addFrag(new Fragment2(), "Item2");
 adapter.addFrag(new Fragment3(), "Item3");
 viewPager.setAdapter(adapter);

3-After that write custom adapter definition

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 addFrag(Fragment fragment, String title) {
        mFragmentList.add(fragment);
        mFragmentTitleList.add(title);
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return mFragmentTitleList.get(position);
    }