FragmentPagerAdapter not working on fragment's recreation

Question

I'm using ViewPager with PagerTabStrip in fragment A and everything works fine. Items are populated. ...Until I replace A with B and then replace again B with A.

fragment xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.view.ViewPager
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent" >

<android.support.v4.view.PagerTabStrip
    android:id="@+id/pager_header"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="top"
    android:background="#222222"
    android:textColor="@color/blue" />

</android.support.v4.view.ViewPager>

Debuggin shows that after second replacement getItem(int position) is never reached in FragmentPagerAdapter. Tabs are empty.

Adapter for tabs:

    private class ChannelsFragmentPagerAdapter extends FragmentPagerAdapter {
    final int PAGE_COUNT = dataChannelsList.size();

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

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

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

    @Override
    public Fragment getItem(int position) {

//This switch isnt reached for second replacement. Dunno why
        switch (position){
            case 0:
                return FragmentChannelsUkr.newInstance();
            case 1:
                return FragmentChannelsRus.newInstance();
            case 2:
                return FragmentChannelsPol.newInstance();
            default:
                return null;
        }
    }
}
}

But again if I rotate the phone when tabs are empty they suddenly recreated in normal usual way.

the adapter call in onCreateView():

   View rootView = inflater.inflate(R.layout.fragment_channels,container, false);
    ViewPager viewPager = (ViewPager) rootView.findViewById(R.id.pager);
    viewPager.setAdapter(new ChannelsFragmentPagerAdapter(getFragmentManager()));

Any ideas what invokes such behaviour? Appreciate any help with explanation.

Tell if some more code needed

Answer 1

You might be running out of memory or it would turn out to be a huge process reloading your fragments again. Try using FragmentStatePagerAdapter instead of FragmentPagerAdapter.