[dev] App closes when trying to backpress from inner fragment

[vkay94]

Checklist

• I am using the latest version - 0.20.8 dev
• I checked, but didn't find any duplicates (open OR closed) of this issue in the repo.
• I have read the contribution guidelines given at https://github.com/TeamNewPipe/NewPipe/blob/HEAD/.github/CONTRIBUTING.md.
• This issue contains only one bug. I will open one issue for every bug report I want to file.

Steps to reproduce the bug

There are many ways to trigger this error. Here's an example:

1. Open the search fragment
2. Backpress / tap on the arrow icon to return to home

Actual behaviour

The app closes with the below error.

Expected behavior

No crash

Screenshots/Screen recordings

Logs

Exception

• User Action: ui error
• Request: App crash, UI failure
• Content Country: DE
• Content Language: de-DE
• App Language: de_DE
• Service: none
• Version: 0.20.8
• OS: Linux Android 8.1.0 - 27

Crash log

java.lang.IllegalStateException: Fragment no longer exists for key f0: unique id 12e9a614-795b-4b2c-bdc2-4964cc0b2345
	at androidx.fragment.app.FragmentManager.getFragment(FragmentManager.java:772)
	at androidx.fragment.app.FragmentStatePagerAdapterMenuWorkaround.restoreState(FragmentStatePagerAdapterMenuWorkaround.java:311)
	at androidx.viewpager.widget.ViewPager.onRestoreInstanceState(ViewPager.java:1461)
	at android.view.View.dispatchRestoreInstanceState(View.java:17706)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3745)
	at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3751)
	at android.view.View.restoreHierarchyState(View.java:17684)
	at androidx.fragment.app.Fragment.restoreViewState(Fragment.java:573)
	at androidx.fragment.app.FragmentStateManager.restoreViewState(FragmentStateManager.java:356)
	at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1189)
	at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1356)
	at androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1434)
	at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1497)
	at androidx.fragment.app.BackStackRecord.executePopOps(BackStackRecord.java:510)
	at androidx.fragment.app.FragmentManager.executeOps(FragmentManager.java:2166)
	at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1992)
	at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1947)
	at androidx.fragment.app.FragmentManager.popBackStackImmediate(FragmentManager.java:658)
	at androidx.fragment.app.FragmentManager.popBackStackImmediate(FragmentManager.java:569)
	at androidx.fragment.app.FragmentManager.handleOnBackPressed(FragmentManager.java:541)
	at androidx.fragment.app.FragmentManager$1.handleOnBackPressed(FragmentManager.java:350)
	at androidx.activity.OnBackPressedDispatcher.onBackPressed(OnBackPressedDispatcher.java:192)
	at androidx.activity.ComponentActivity.onBackPressed(ComponentActivity.java:314)
	at org.schabi.newpipe.MainActivity.onBackPressed(MainActivity.java:591)
	at android.app.Activity.onKeyUp(Activity.java:2980)
	at android.view.KeyEvent.dispatch(KeyEvent.java:2720)
	at androidx.core.view.KeyEventDispatcher.activitySuperDispatchKeyEventPre28(KeyEventDispatcher.java:137)
	at androidx.core.view.KeyEventDispatcher.dispatchKeyEvent(KeyEventDispatcher.java:87)
	at androidx.core.app.ComponentActivity.dispatchKeyEvent(ComponentActivity.java:140)
	at androidx.appcompat.app.AppCompatActivity.dispatchKeyEvent(AppCompatActivity.java:569)
	at androidx.appcompat.view.WindowCallbackWrapper.dispatchKeyEvent(WindowCallbackWrapper.java:59)
	at androidx.appcompat.app.AppCompatDelegateImpl$AppCompatWindowCallback.dispatchKeyEvent(AppCompatDelegateImpl.java:3054)
	at androidx.appcompat.view.WindowCallbackWrapper.dispatchKeyEvent(WindowCallbackWrapper.java:59)
	at com.android.internal.policy.DecorView.dispatchKeyEvent(DecorView.java:354)
	at android.view.ViewRootImpl$ViewPostImeInputStage.processKeyEvent(ViewRootImpl.java:4733)
	at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:4605)
	at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4147)
	at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4200)
	at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4166)
	at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:4293)
	at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:4174)
	at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:4350)
	at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4147)
	at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4200)
	at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4166)
	at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:4174)
	at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:4147)
	at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:4200)
	at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:4166)
	at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:4326)
	at android.view.ViewRootImpl$ImeInputStage.onFinishedInputEvent(ViewRootImpl.java:4487)
	at android.view.inputmethod.InputMethodManager$PendingEvent.run(InputMethodManager.java:2435)
	at android.view.inputmethod.InputMethodManager.invokeFinishedInputEventCallback(InputMethodManager.java:1998)
	at android.view.inputmethod.InputMethodManager.finishedInputEvent(InputMethodManager.java:1989)
	at android.view.inputmethod.InputMethodManager$ImeInputEventSender.onInputEventFinished(InputMethodManager.java:2412)
	at android.view.InputEventSender.dispatchInputEventFinished(InputEventSender.java:141)
	at android.os.MessageQueue.nativePollOnce(Native Method)
	at android.os.MessageQueue.next(MessageQueue.java:325)
	at android.os.Looper.loop(Looper.java:142)
	at android.app.ActivityThread.main(ActivityThread.java:6494)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:440)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

---

Device info

• Android version/Custom ROM version: Android 8.1.0 / 10.0
• Device model: S4 / S4 Mini

[TobiGr]

That does not occur at c90696e, but at 09312a9. So this was caused by #4814
CC @Isira-Seneviratne any ideas how to fix that?