IllegalStateException: Can't change tag of fragment was android:switcher now android:switcher

Question

My activity uses TabLayout + ViewPager.

The number of tabs and pages here are dynamic depending on the data fetch from the server.

Th

Answer 1

The FragmentPagerAdapter already caches the Fragments for you. Each fragment is assigned a tag, and then the FragmentPagerAdapter tries to call findFragmentByTag. It only calls getItem() if the result from findFragmentByTag is null.

You're probably getting this error because you're adding the same fragment instance to the list. You should create a new instance for each page.

Example form document :

//...
      public static class MyAdapter extends FragmentPagerAdapter {
            public MyAdapter(FragmentManager fm) {
                super(fm);
            }

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

            @Override
            public Fragment getItem(int position) {
                return ArrayListFragment.newInstance(position);// IMPORTANT
            }
        }
    //..

Refer :FragmentPagerAdapter

Main thread : Retrieve a Fragment from a ViewPager