Android Fragment isAdded 在配置更改后返回 false（屏幕旋转）

Question

I have an Activity with a ViewPager2. A ScreenSlidePagerAdapter is creating my 4 Fragments in the ViewPager. After sliding through the fragments isAdded returns true for every Fragment. After a screen rotation configuration change isAdded returns false for all Fragments, but I have to keep them added. Is there a possibility to re-add them, or how can I keep them added?

UPDATE 1: after the configuration change isAdded is only false for all fragments which I slided through before the configuration change. For the other Fragments isAdded gets true also after the configuration change.

The Adapter code is:

    private inner class ScreenSlidePagerAdapter(fa: FragmentActivity, data: Bundle) : FragmentStateAdapter(fa) {
        val fragmentBundle: Bundle = data


        override fun createFragment(position: Int): Fragment {
            when (position) {
                1 -> { 
                    sliderFragment2.arguments = fragmentBundle                                  
                    return sliderFragment2
                }
                2 -> {
                    sliderFragment3.arguments = fragmentBundle
                    return sliderFragment3
                }
                3 -> {
                    sliderFragment4.arguments = fragmentBundle
                    return sliderFragment4
                }
                else -> {
                    sliderFragment1.arguments = fragmentBundle
                    return sliderFragment1
                }
            }
        }

        override fun getItemCount(): Int {
            return NUM_PAGES
        }
    }
}

Answer 1

 public class TestActivity extends FragmentActivity{ @Override public void onCreate(Bundle savedInstanceState){ //Use null, no restore super.onCreate(null); ... } }