NavBackStackEntry lifecycle not updated correctly when there are multiple FloatingWindow destinations on the back stack [287505132]

Fixed

Bug

Status Update

No update yet.

Description

ga...@gmail.com

created issue #1

Jun 16, 2023 07:18PM

Component used: Navigation
Version used: 2.6.0
Devices/Android versions reproduced on: Emulator Android 13

Very simple scenario for demo purposes:
1. MainFragment navigates to Dialog1Fragment
2. Dialog1Fragment navigates to Dialog2Fragment
3. Dialog2Fragment navigates back

This will result in the lifecycle of Dialog1Fragment's NavBackStackEntry to go back into `ON_START` but it will never go back to `ON_RESUME` even though it is now the top destination on the stack.

I've attached a small sample project with these 3 fragments

test.zip

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Comments

ga...@gmail.com <ga...@gmail.com> #2Jun 16, 2023 07:45PM

Oh I forgot to mention that I thought it might be connected to this issue: https://issuetracker.google.com/issues/243778589. But after trying 2.5.2 I can say that the issue persists.

jb...@google.com <jb...@google.com> Jun 16, 2023 08:08PM

Assigned to cl...@google.com.

ga...@freeletics.com <ga...@freeletics.com> #3Aug 1, 2023 06:19AM

Please provide a minimal sample project along with the minimal steps to recreate the issue in the project.

cl...@google.com <cl...@google.com> #4Aug 30, 2023 05:38PM

Accepted by cl...@google.com.

Sorry for the delay. I got a working example here: https://github.com/Del-S/issues. The project is set up to crash when navigating to ThirdFragment (nested nav graph) with poping the graph.

I poked into it a little bit and it seems to be connected to SafeArgs gradle plugin. When safe args is used to navigate to ThirdFragment (with nested graph poped) it will try to recreate te parent but there were no arguments passed so it crashes.

Steps to reproduce:

Navigate from Second Fragment to Child nav graph (with non-nullable parameters).
Navigate to Third fragment using SafeArgs and the app crashes.

Crash log:

Process: cz.dels.issues, PID: 1743
java.lang.NullPointerException: null cannot be cast to non-null type kotlin.Long
at androidx.navigation.NavType$Companion$LongType$1.get(NavType.kt:352)
at androidx.navigation.NavType$Companion$LongType$1.get(NavType.kt:342)
at androidx.navigation.NavArgument.verify(NavArgument.kt:76)
at androidx.navigation.NavDestination.addInDefaultArgs(NavDestination.kt:502)
at androidx.navigation.NavController.addEntryToBackStack(NavController.kt:1865)
at androidx.navigation.NavController.addEntryToBackStack$default(NavController.kt:1813)
at androidx.navigation.NavController$navigate$4.invoke(NavController.kt:1721)
at androidx.navigation.NavController$navigate$4.invoke(NavController.kt:1719)
at androidx.navigation.NavController$NavControllerNavigatorState.push(NavController.kt:287)
at androidx.navigation.fragment.FragmentNavigator.navigate(FragmentNavigator.kt:246)
at androidx.navigation.fragment.FragmentNavigator.navigate(FragmentNavigator.kt:162)
at androidx.navigation.NavController.navigateInternal(NavController.kt:260)
at androidx.navigation.NavController.navigate(NavController.kt:1719)
at androidx.navigation.NavController.navigate(NavController.kt:1545)
at androidx.navigation.NavController.navigate(NavController.kt:1472)
at androidx.navigation.NavController.navigate(NavController.kt:1930)
at cz.dels.issues.SecondFragment.onViewCreated$lambda-0(SecondFragment.kt:38)
at cz.dels.issues.SecondFragment.$r8$lambda$XDYnOS_cYrafiNQ5rcCu1WCn0IE(Unknown Source:0)
at cz.dels.issues.SecondFragment$$ExternalSyntheticLambda0.onClick(Unknown Source:2)

Note: If in step 2 SaveArgs is not used then navigation works correctly. More information is here: https://github.com/Del-S/issues/blob/master/app/src/main/java/cz/dels/issues/SecondFragment.kt#L37.

Message last modified on Aug 30, 2023 06:04PM

ap...@google.com <ap...@google.com> #5Aug 31, 2023 07:26PM

Ups a typo: Navigate from ~~Second~~ First Fragment to Child nav graph (with non-nullable parameters).

Note: sorry for the spam but I am not able to edit my own comment.

cl...@google.com <cl...@google.com> #6Aug 31, 2023 07:52PM

Marked as fixed.

This has been fixed and will be available in navigation 2.6.0-alpha08

na...@google.com <na...@google.com> #7Sep 20, 2023 07:16PM

Project: platform/frameworks/support
Branch: androidx-main

commit 6b358154b794a0456b089ac8e548bfb830dd6c22
Author: Clara Fok <clarafok@google.com>
Date: Tue Mar 14 17:56:12 2023

Fix missing non-nullable arg when rebuilding hierarchy

When navigating with NavDirections, args is populated with an empty bundle. This causes issue when we rebuild parent hierarchy while adding a new entry to NavBackStack. If the Entry being rebuilt contains a non-nullalbe arg, i.e. Long, this empty bundle will cause an exception.

Test: ./gradlew navigation:navigation-runtime:cC
Bug: 249988437
Change-Id: I5c8ce739ad9a3428c8a8de13eae391bfff0db5df

M navigation/navigation-runtime/src/androidTest/java/androidx/navigation/NavControllerTest.kt
M navigation/navigation-runtime/src/main/java/androidx/navigation/NavController.kt

https://android-review.googlesource.com/2488855

na...@google.com <na...@google.com> #8Jan 24, 2024 07:53PM

The following release(s) address this bug.It is possible this bug has only been partially addressed:

androidx.navigation:navigation-runtime:2.6.0-alpha08