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lc...@gmail.com <lc...@gmail.com> #2
Oh I forgot to mention that I thought it might be connected to this issue:
jo...@gmail.com <jo...@gmail.com> #3
Please provide a minimal sample project along with the minimal steps to recreate the issue in the project.
il...@google.com <il...@google.com>
ap...@google.com <ap...@google.com> #4
Sorry for the delay. I got a working example here:
I poked into it a little bit and it seems to be connected to
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:
jb...@google.com <jb...@google.com> #5
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.
ec...@gmail.com <ec...@gmail.com> #6
This has been fixed and will be available in navigation 2.6.0-alpha08
jb...@google.com <jb...@google.com> #7
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
Description
Component used: Navigation
Version used: 2.4.0-alpha09
Devices/Android versions reproduced on: Not device dependent, code generation issue
Safeargs plugin on 2.4.0-alpha09 since it implemented this behaviour change below
When generating arguments, Safe Args now puts parameters without default values before those with default values. (I89709, b/198493585)
This bahvious change seesms to cause the side effect of compilation time errors in the genrated argument files. As far as I know this affects both kotlin and java generated files.
e.g.
XML navgraph destination (
NavCompFingerPrintAuthDialogFragment
)As you can see the arguments with no default values are not defined first.
this will generate the argument data object shown below with the behavios change which puts the arguments with no default values first in the constructor.
Now the problem is that in the
NavCompFingerPrintAuthDialogFragmentArgs.fromBundle(bundle: Bundle): NavCompFingerPrintAuthDialogFragmentArgs
companion function does not use named arguments when creating aNavCompFingerPrintAuthDialogFragmentArgs
from a bundle. And it uses the arguments in the order that it was defined in the navgraph and not in the order that theNavCompFingerPrintAuthDialogFragmentArgs
data object expects in its constructor. The same issue also apples for the companion functionfromSavedStateHandle(savedStateHandle: SavedStateHandle):NavCompFingerPrintAuthDialogFragmentArgs
but compilation will fail at the earliest point so it was not reported in the error. But from what i can see in the genrated code, its will have the same problem too.One solution is to just use named arguments for kotlin generated files, but it does not solve the issue for java generated files. So perhaps putting the arguments in the order of the
behavior change
mention above shld solve the issue.