Version v3.0.0.173.844e4d6(15)
Stacktrace
androidx.fragment.app.FragmentTransaction.doAddOp (FragmentTransaction.java:249);
androidx.fragment.app.BackStackRecord.doAddOp (BackStackRecord.java:183);
androidx.fragment.app.FragmentTransaction.add (FragmentTransaction.java:171);
androidx.viewpager2.adapter.FragmentStateAdapter.placeFragmentInViewHolder (FragmentStateAdapter.java:339);
androidx.viewpager2.adapter.FragmentStateAdapter.onViewAttachedToWindow (FragmentStateAdapter.java:276);
androidx.viewpager2.adapter.FragmentStateAdapter.onViewAttachedToWindow (FragmentStateAdapter.java:67);
androidx.recyclerview.widget.RecyclerView.dispatchChildAttached (RecyclerView.java:7556);
androidx.recyclerview.widget.RecyclerView$5.addView (RecyclerView.java:860);
androidx.recyclerview.widget.ChildHelper.addView (ChildHelper.java:107);
androidx.recyclerview.widget.RecyclerView$LayoutManager.addViewInt (RecyclerView.java:8601);
androidx.recyclerview.widget.RecyclerView$LayoutManager.addView (RecyclerView.java:8559);
androidx.recyclerview.widget.RecyclerView$LayoutManager.addView (RecyclerView.java:8547);
androidx.recyclerview.widget.LinearLayoutManager.layoutChunk (LinearLayoutManager.java:1641);
androidx.recyclerview.widget.LinearLayoutManager.fill (LinearLayoutManager.java:1587);
androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren (LinearLayoutManager.java:665);
androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2 (RecyclerView.java:4134);
androidx.recyclerview.widget.RecyclerView.onMeasure (RecyclerView.java:3540);
androidx.viewpager2.widget.ViewPager2.onMeasure (ViewPager2.java:498);
androidx.appcompat.widget.LinearLayoutCompat.measureChildBeforeLayout (LinearLayoutCompat.java:1401);
androidx.appcompat.widget.LinearLayoutCompat.measureVertical (LinearLayoutCompat.java:685);
androidx.appcompat.widget.LinearLayoutCompat.onMeasure (LinearLayoutCompat.java:575);
androidx.coordinatorlayout.widget.CoordinatorLayout.onMeasure (CoordinatorLayout.java:831);
androidx.appcompat.widget.ContentFrameLayout.onMeasure (ContentFrameLayout.java:145);
Reason
java.lang.IllegalStateException: Fragment null must be a public static class to be properly recreated from instance state.
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