navigateUp() causes navgraph issue when moving from FragmentTypeB to FragmentTypeB [123552990]

Fixed

Bug

Status Update

No update yet.

Description

an...@seventhbeam.com

created issue #1

Jan 29, 2019 06:09AM

Component used: Navigation
Version used: 1.0.0-alpha11

I'm seeing some strange behaviour when pressing back button and transistion back to a fragment from a fragment of the same id.
My app uses some generic fragment structures that are driven by args passed in, as such there are places like:

FragmentA -> FragmentB -> FragmentB -> FragmentC

However if the back button is pressed on the second instance of FragmentB, FragmentA is replaced in the navhost while the navgraph correctly displays in the toolbar. Forward navigation from this point however is missing from the navgraph and results in an IllegalStateException with the action 'not found' in the graph, unless the back button is pressed again (pushing the navgraph destination back to FragmentA)

Is this intended behaviour? If so is there a way to declare FragmentB as 'stackable'?

Comments

so...@gmail.com <so...@gmail.com> #2Jan 29, 2019 10:56AM

What about Enums? Enum is a type-safe way to pass navigation arguments.
Will Enums be covered in this issue as part of Serializable or will have own handled separately?
Because for enum you can provide a reasonable default value but for Parcelable or Serializable only @null

so...@gmail.com <so...@gmail.com> #3Jan 29, 2019 11:07AM

Please add support for Serializable objects so Enums can be used.

so...@gmail.com <so...@gmail.com> #4Jan 29, 2019 11:34AM

Support of Serializable objects is not enough for enums, you definitely need also the support of default values.

il...@google.com <il...@google.com> Jan 29, 2019 04:05PM

Assigned to il...@google.com.

il...@google.com <il...@google.com> Jan 30, 2019 06:49PM

Accepted by il...@google.com.

ap...@google.com <ap...@google.com> #5Jan 30, 2019 07:50PM

Marked as fixed.

Project: platform/frameworks/support
Branch: androidx-master-dev

commit 6f59e3d74d0da5a4bf79c8480f56964e3af47f1c
Author: Wojtek Kaliciński <wkal@google.com>
Date: Mon Jul 23 20:17:19 2018

Support more types for args

Provides support for Serializable, enums,
as well as arrays of primitive types and Parcelables
in Navigation arguments.

Only enums support default values other than @null,
in the form of the enum literal (without class name),
e.g. app:defaultValue="READ"

Test: unit tests updated
BUG: 111487504
BUG: 111316353
Change-Id: I7e5abbc8ed0950bfdef292342dbe1fb34a5c4b17

M navigation/runtime/src/androidTest/java/androidx/navigation/NavInflaterTest.kt
A navigation/runtime/src/androidTest/java/androidx/navigation/test/TestEnum.java
M navigation/runtime/src/androidTest/res/navigation/nav_default_arguments.xml
M navigation/runtime/src/main/java/androidx/navigation/NavInflater.java
M navigation/safe-args-generator/src/main/kotlin/androidx/navigation/safe/args/generator/NavParser.kt
M navigation/safe-args-generator/src/main/kotlin/androidx/navigation/safe/args/generator/NavParserErrors.kt
M navigation/safe-args-generator/src/main/kotlin/androidx/navigation/safe/args/generator/NavWriter.kt
M navigation/safe-args-generator/src/main/kotlin/androidx/navigation/safe/args/generator/Types.kt
M navigation/safe-args-generator/src/tests/kotlin/androidx/navigation/safe/args/generator/NavParserTest.kt
M navigation/safe-args-generator/src/tests/kotlin/androidx/navigation/safe/args/generator/NavWriterTest.kt
M navigation/safe-args-generator/src/tests/test-data/expected/nav_writer_test/MainFragmentArgs.java
M navigation/safe-args-generator/src/tests/test-data/expected/nav_writer_test/Next.java
M navigation/safe-args-generator/src/tests/test-data/naive_test.xml

https://android-review.googlesource.com/720246

https://goto.google.com/android-sha1/6f59e3d74d0da5a4bf79c8480f56964e3af47f1c

il...@google.com <il...@google.com> #6Jan 30, 2019 08:33PM

This is fixed internally and will be available in 1.0.0-alpha08

ch...@gmail.com <ch...@gmail.com> #7Feb 5, 2019 06:44PM

What happened if I declaire app:argType="androidx.navigation.test.TestEnum" and turn on proguard/R8? Because both ProGuard and R8 will optimize trivial enums into ints.

il...@google.com <il...@google.com> #8Feb 5, 2019 06:50PM

Since you need to explicitly keep argTypes as per

https://issuetracker.google.com/issues/122634648, they'll be kept.

pi...@gmail.com <pi...@gmail.com> #9Mar 22, 2025 07:02PM

Thanks. Just saw the latest documentation.

pi...@gmail.com <pi...@gmail.com> #10Mar 22, 2025 07:05PM

Comment has been deleted.

Message last modified on Mar 22, 2025 07:06PM