Фрагменты не загружаются внутри другого фрагмента

У меня есть панель мониторинга, которая содержит четыре вкладки, скажем, A,B, C и D. В каждом фрагменте у меня есть еще два дочерних фрагмента,скажем, для A — (a,b), B — (a, b), C — (a, b) и для D — (a, b). Когда я запускаю приложение его загрузки всех фрагментов. Теперь, если я передаю данные от фрагмента A к фрагменту B, если я нажму на фрагмент B его не загрузка. Только когда я нажимаю на вкладку A и нажмите на вкладку B только страница загружается.

public class Dashboard extends AppCompatActivity {
    private Toolbar toolbar;
    private TabLayout tabLayout,tablayout_top;
    private ViewPager viewPager;
    public List<Task_data> tasklist = new ArrayList<>();
    private TaskFragmentAdapter tadapter;
    private final Task_main_fragment mfragment0;

    public Dashboard() {
        mfragment0 = null;
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_dashboard);


        toolbar = (Toolbar) findViewById(R.id.toolbar_home_dashboard);
        setSupportActionBar(toolbar);

        viewPager = (ViewPager) findViewById(R.id.viewpager_home_dashboard);
        setupViewPager(viewPager);

        final int PAGE = 0;

        viewPager.setOnTouchListener(new View.OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {

                if (viewPager.getCurrentItem() == PAGE) {
                    viewPager.setCurrentItem(PAGE - 1, false);
                    viewPager.setCurrentItem(PAGE, false);
                    return true;    
                }
                return false;
            }
        });

        viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {

            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
            }

            @Override
            public void onPageSelected(int position) {
                if (position == 2) {
                    //do your Staff
                    Toast.makeText(Dashboard.this, "You are currently working on snags page", Toast.LENGTH_SHORT).show();
                    //now I need to refresh the fragments in onpage selected page.
                }
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });

/*        viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(final int i, final float v, final int i2) {
            }
            @Override
            public void onPageSelected(final int i) {
                YourFragmentInterface fragment = (YourFragmentInterface) mPagerAdapter.instantiateItem(mViewPager, i);
                if (fragment != null) {Toast.makeText(Dashboard.this, "you are on task page", Toast.LENGTH_SHORT).show();
                    fragment.fragmentBecameVisible();
                }
            }
            @Override
            public void onPageScrollStateChanged(final int i) {
            }
        });*/

        tabLayout = (TabLayout) findViewById(R.id.tabs_home_dashboard);
        tabLayout.setupWithViewPager(viewPager);

       /* for(int i=0;i<tabLayout.getTabCount();i++){

            TabLayout.Tab tab =tabLayout.getTabAt(i);
            RelativeLayout relativeLayout=(RelativeLayout)LayoutInflater.from(this).inflate(R.layout.tab_layout,tabLayout,false);
            tab.setCustomView(relativeLayout);
            tab.select();

        }*/
        setupTabIcons();

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
     getMenuInflater().inflate(R.menu.menu_dashboard,menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.Refresh_dashboard:

                Toast.makeText(getApplicationContext(), "The page is about to get refresh", Toast.LENGTH_SHORT).show();
                //getRefresh(); Iam calling a m

                break;
            case R.id.Account:

                startActivity(new Intent(getApplicationContext(), Profile.class));


                return  true;
            case R.id.Homepage_dashboard:

                startActivity(new Intent(getApplicationContext(),homepage.class));
                return  true;

            case R.id.sync_dashboard:

                startActivity(new Intent(getApplicationContext(),sync.class));
                return true;

        }
        return super.onOptionsItemSelected(item);
    }

    private void setupTabIcons() {
        TextView tabOne = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
        tabOne.setText("Home");
        tabOne.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.schld, 0, 0);
        tabLayout.getTabAt(0).setCustomView(tabOne);

        TextView tabTwo = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
        tabTwo.setText("Schedule");
        tabTwo.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.schld, 0, 0);
        tabLayout.getTabAt(1).setCustomView(tabTwo);

        TextView tabThree = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
        tabThree.setText("Tasks");
        tabThree.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.taskimg, 0, 0);
        tabLayout.getTabAt(2).setCustomView(tabThree);

        TextView tabfour = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
        tabfour.setText("Drafts");
        tabfour.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.cloud, 0, 0);
        tabLayout.getTabAt(3).setCustomView(tabfour);

      /*  TextView tabfive = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
        tabfive.setText("Sync");
        tabfive.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.cloud, 0, 0);
        tabLayout.getTabAt(4).setCustomView(tabfive);*/

      /*  TextView tabfive = (TextView) LayoutInflater.from(this).inflate(R.layout.custom_tab, null);
        tabfive.setText("More");
        tabfive.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.ic_action_help, 0, 0);
        tabLayout.getTabAt(4).setCustomView(tabfive);*/
    }

    /**
     * Adding fragments to ViewPager
     * @param viewPager
     */
    private void setupViewPager(ViewPager viewPager) {
        ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
        adapter.addFrag(new A(),"ONE");
        adapter.addFrag(new B(),"TWO");
        adapter.addFrag(new C(), "THREE");
        adapter.addFrag(new D(), "FOUR");
        viewPager.setAdapter(adapter);
    }

    class ViewPagerAdapter extends FragmentStatePagerAdapter {
        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);
        }
    }
}

Вот мой фрагмент кода, который содержит еще два фрагмента a,b

 public class B extends Fragment {
    private TabLayout tabLayout,tablayout_top;
    private ViewPager viewPager;
    View view;
    private int[] tabIcons = {
            R.drawable.ic_tab_favourite,
            R.drawable.ic_tab_call,
            R.drawable.ic_tab_contacts
    };
   /* @Bind(R.id.title) TextView name;
    @Bind(R.id.job_title) TextView jobTitle;*/
    public Schedule_Fragment(){

    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        view = inflater.inflate(R.layout.activity_schedule__fragment,container, false);
        super.onCreate(savedInstanceState);

        ButterKnife.inject(this, view);
        viewPager =ButterKnife.findById(view,R.id.viewPager_top_schedule);
        setupViewPager(viewPager);
        TabLayout tabLayout = ButterKnife.findById(view,R.id.tabs_top_home_schedule);
        tabLayout.setupWithViewPager(viewPager);
      /*  setupTabicons();*/

        return view;
    }

    private void setupTabicons() {
        TextView tabOne = (TextView) LayoutInflater.from(getContext()).inflate(R.layout.custom_tab, null);
        tabOne.setText("Snags");
        tabOne.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.ic_tab_favourite, 0, 0);
        tabLayout.getTabAt(0).setCustomView(tabOne);

        TextView tabTwo = (TextView) LayoutInflater.from(getContext()).inflate(R.layout.custom_tab, null);
        tabTwo.setText("Desnags");
        tabTwo.setCompoundDrawablesWithIntrinsicBounds(0, R.drawable.ic_tab_call, 0, 0);
        tabLayout.getTabAt(1).setCustomView(tabTwo);
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        ButterKnife.reset(this);
    }

    private void setupViewPager(ViewPager viewPager) {
        ViewPagerAdapterTop adaptertop = new ViewPagerAdapterTop(getChildFragmentManager());
        adaptertop.addFragment(new a(),"Snags");
        adaptertop.addFragment(new b(),"Desnags");
        viewPager.setAdapter(adaptertop);
    }

    class  ViewPagerAdapterTop extends FragmentPagerAdapter{
        private final List<Fragment> mFragments = new ArrayList<>();
        private final List<String> mFragmentTitles = new ArrayList<>();

        public ViewPagerAdapterTop(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);
        }
    }
}

Теперь эти два фрагмента a, b не загружаются, когда я нажимаю на фрагмент B. только фрагмент B загружается, когда мы нажимаем на фрагмент A и возвращаемся к фрагменту B. пожалуйста, помогите мне, поскольку я новичок в Android.

1 ответ