Graph equality seems to be wrong on the newest version of Navigation (2.7.5) [311414915]

Fixed

Bug

Status Update

No update yet.

Description

zi...@gmail.com

created issue #1

Nov 17, 2023 07:59AM

Component used: Navigation
Version used: 2.7.5
Devices/Android versions reproduced on: Emulator Pixel 6a API 33 arm64

Hello! It seems that with the newest update (2.7.5) setGraph no longer works in our specific case. I’m wondering if it is related to the equals change[1]. For our graph if (_graph != graph) inside public open fun setGraph(graph: NavGraph, startDestinationArgs: Bundle?) returns true on 2.7.4 but false on 2.7.5. The line with nodes.valueIterator().asSequence().all { it == nodes.get(it.id) } looks suspicious. Shouldn’t it check nodes from the other graph?

[1] https://android.googlesource.com/platform/frameworks/support/+/d22366d59a46aa16aa79d1d691cd5cb55f56c378%5E%21/#F1

Comments

jb...@google.com <jb...@google.com> #2Nov 17, 2023 08:38PM

Status: New

Nested scrolling works partially (as per

http://b/122818889). Let's discuss if we need full support and if so make sure it works.

zi...@gmail.com <zi...@gmail.com> #3Nov 20, 2023 07:53AM

Hi!

What is 'partially' exactly?
How do I see it?
Thanks!

jb...@google.com <jb...@google.com> Nov 28, 2023 08:30PM

Assigned to jb...@google.com.

ap...@google.com <ap...@google.com> #4Nov 29, 2023 05:06PM

As of now:
- Nesting scroll views with a scroll direction perpendicular to the ViewPager2's orientation inside ViewPager2 works
- Nesting scroll views with a scroll direction parallel to the ViewPager2's orientation inside ViewPager2 does not work

jb...@google.com <jb...@google.com> #5Nov 29, 2023 05:08PM

Marked as fixed.

Horizontal ViewPager2 not correctly working into a vertical RecyclerView
Set a setNestedScrollingEnabled to the RecyclerView into the ViewPager2 (across reflection) resolves the problem

zi...@gmail.com <zi...@gmail.com> #6Nov 30, 2023 07:28PM

ageevvalentin@gmail.com, could you provide a sample app? I'd like to learn more about the circumstances that cause the problem; putting a clean ViewPager2 inside a clean RecyclerView seems to work fine, so there must be other factors involved.

na...@google.com <na...@google.com> #7Dec 13, 2023 06:33PM

Added a patch for androidx-master-dev that demos a horizontal ViewPager2 inside a vertical RecyclerView.

Verified that it works correctly on a:
- Nexus 4 emulator with API 17
- Nexus 5X emulator with API 28
- Pixel 2 device with API 29

To reproduce:
- Check out the Android Jetpack source (at commit 256899f482ff85cddfb050f37550be7b5ec927ef) (see steps in [1])
- Apply the patch (`git apply 0001-Add-sample-where-a-horizontal-ViewPager2-is-nested-i.patch`)
- Build and install viewpager2's integration-tests app: `./gradlew viewpager2:integration-tests:testapp:installDebug`
- Run it

Closing the issue for now, but please reopen if you have a minimal reproduction app

[1]

https://android.googlesource.com/platform/frameworks/support/+/256899f482ff85cddfb050f37550be7b5ec927ef

na...@google.com <na...@google.com> #8Jan 24, 2024 07:52PM

Re-opening as requested by a few users. Narrowed down the focus to nested scrolling elements with the same scroll direction.