Passing a string between fragments in a viewpager doesnt work properly

Question

My main activity has 3 tabs, each one loads a different fragment. i am trying to pass data from fragment 1 to fragment 3, but it doesnt work

all 3 fragment can be loaded, but the problem is that only 1&2 are loaded when i start the application. so when i run the application and i want to pass a string from fragment 1 to 3 it doesnt work because it doesnt exist yet. how can i change this?

I am using Eventbus (https://github.com/greenrobot/EventBus) for the communication between fragments.

public class MainActivity extends AppCompatActivity {

    private Toolbar mToolbar;
    private TabLayout mTabLayout;
    private ViewPager mPager;
    private MyPagerAdapter mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mAdapter = new MyPagerAdapter(getSupportFragmentManager());
        mToolbar = (Toolbar) findViewById(R.id.app_bar);
        setSupportActionBar(mToolbar);
        mTabLayout = (TabLayout) findViewById(R.id.tab_layout);

        mPager = (ViewPager) findViewById(R.id.pager);
        mPager.setAdapter(mAdapter);

        mTabLayout.setTabsFromPagerAdapter(mAdapter);

        mTabLayout.setupWithViewPager(mPager);
        mPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(mTabLayout));
    }

    @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_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    public static class MyFragment extends Fragment {
        public static final java.lang.String ARG_PAGE = "arg_page";

        public MyFragment() {
        }

        public static MyFragment newInstance(int pageNumber) {
            MyFragment myFragment = new MyFragment();
            Bundle arguments = new Bundle();
            arguments.putInt(ARG_PAGE, pageNumber + 1);
            myFragment.setArguments(arguments);
            return myFragment;
        }
    }



class MyPagerAdapter extends FragmentStatePagerAdapter {

    public MyPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
        Fragment fragment = MainActivity.MyFragment.newInstance(position); //FRAGMENT fragment;
        switch (position) {
            case 0:
                fragment = new Fragment1();
                break;
            case 1:
                fragment = new Fragment2();
                break;
            case 2:
                fragment = new Fragment3();
                break;
            default:
                break;
        }
        return fragment;
    }


    @Override
    public int getCount() {
        return 3;
    }

    @Override
    public CharSequence getPageTitle(int position) { //set tab names

        switch (position) {
            case 0:
                return "Thread";
            case 1:
                return "AsyncTask";
            case 2:
                return "TODO";
        }
        return null;
    }}}

Answer 1

Minimum number of pages you want your adapter to load is set this way

Viewpager.setOffscreenPageLimit(3);