Add a method `toSavedStateHandle` to SafeArgs [193353880]

Fixed

Feature Request

Status Update

No update yet.

Description

hi...@a8c.com

created issue #1

Jul 12, 2021 12:22PM

Component used: Navigation Version used: 2.4.0-alpha02

With the addition of the function fromSavedStateHandle, it became easier to pass SafeArgs to the ViewModels using Hilt. But when trying to test those ViewModels, we still have to create the SavedStateHandle by hand, which is not optimal.

I would suggest generating a method tSavedStateHandle similar to the toBundle one, that creates a SavedStateHande object holding the arguments of the SafeArgs we need to test against, and that we can pass directly to the ViewModel's constructor.

Comments

br...@gmail.com <br...@gmail.com> #2Jul 12, 2021 12:40PM

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.

br...@gmail.com <br...@gmail.com> #3Jul 12, 2021 02:26PM

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

il...@google.com <il...@google.com> Jul 19, 2021 11:21PM

Assigned to jb...@google.com.

ap...@google.com <ap...@google.com> #4Jul 30, 2021 07:18PM

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.

jb...@google.com <jb...@google.com> #5Aug 6, 2021 04:32PM

Marked as fixed.

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.

hi...@a8c.com <hi...@a8c.com> #6Aug 9, 2021 11:10AM

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

Issue 193353880