Fragment transition issues that won't happen when FragmentManager.enableNewStateManager(false) is called [167092035]

Fixed

Bug

Status Update

No update yet.

Description

tf...@gmail.com

created issue #1

Aug 31, 2020 12:46PM

Component used: Fragment

Version used: 1.3.0-alpha08

Devices/Android versions reproduced on: Pixel 4 / Android 10

Sample project: https://github.com/tfcporciuncula/broken-transition

Fragment blinking issue video: https://github.com/tfcporciuncula/broken-transition/blob/master/videos/red%20blink.mp4 (you might need to go frame by frame in the video to see the blinking)

Back issue video: https://github.com/tfcporciuncula/broken-transition/blob/master/videos/back%20regular.mp4 (and here's a video with the regular behavior for this)

I have very simple slide transitions defined by myself (exactly like these ones) and I noticed they got a bit broken after I updated everything to the latest version. I decided to call FragmentManager.enableNewStateManager(false) to check if the issues were related to the new state manager, and indeed the issues were gone after that.

The first issue I noticed was that the fragment I'm transitioning to blinks in the very beginning of the transition. I managed to reproduce it in the very simple example I'm linking here, but for some reason the issue seems to happen more frequently on my actual app and not that often in the sample, even though it still happen fairly often. It feels like it's a single frame blink, so it's a little hard to see but it's definitely noticeable when it happens.

There's a second issue I noticed while testing this with a super slow transition duration: when I tap back during the transition from the blue fragment to the red fragment, I end up in a blank screen. If I have the enableNewStateManager(false) call, it simply moves to the end of the transition and transitions back from the blue fragment to the red, certainly a better behavior.

Comments

tf...@gmail.com <tf...@gmail.com> #2Aug 31, 2020 01:34PM

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

commit 57ca221882695bd6a52549f4d9ea3b812e6fe87c
Author: Simon Schiller <simonschiller@users.noreply.github.com>
Date: Mon Mar 22 16:09:30 2021

[GH] [FragmentStrictMode] Detect <fragment> tag usage

## Proposed Changes

- Detect `<fragment>` tag usage inside XML layouts

## Testing

Test: See `FragmentStrictModeTest#detectFragmentTagUsage`

## Issues Fixed

Fixes: 153738235

This is an imported pull request from

https://github.com/androidx/androidx/pull/141.

Resolves #141
Github-Pr-Head-Sha: 4ea052596e4341b9f11bcf335e2bc38045a91f19
GitOrigin-RevId: 62e7487aa4874eef6bb556490e193717cf937251
Change-Id: Iae48578e85e4e4897f806d7ade2e2a660adf9479

M fragment/fragment/api/public_plus_experimental_current.txt
M fragment/fragment/api/restricted_current.txt
M fragment/fragment/src/androidTest/java/androidx/fragment/app/strictmode/FragmentStrictModeTest.kt
M fragment/fragment/src/main/java/androidx/fragment/app/FragmentLayoutInflaterFactory.java
M fragment/fragment/src/main/java/androidx/fragment/app/strictmode/FragmentStrictMode.java
A fragment/fragment/src/main/java/androidx/fragment/app/strictmode/FragmentTagUsageViolation.java

https://android-review.googlesource.com/1649748

il...@google.com <il...@google.com> Sep 16, 2020 06:31PM

Assigned to jb...@google.com.

ap...@google.com <ap...@google.com> #3Sep 30, 2020 08:54PM

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

commit 0d5272e6e4fe56f09e5246d42c0930bcc50e26fa
Author: Jeremy Woods <jbwoods@google.com>
Date: Tue Sep 29 23:38:37 2020

Fix issues caused by interrupting exit effects

When removing a fragment using an exit effect, then reversing the exit
operation (by using the back button) to an enter effect, while exiting
the fragment only ever makes it to AWAITING_EXIT_EFFECTS so the view is
not destroyed. This means that when the fragment attempts to reenter it
does not go through createView() which gets the view ready for effects.

For this case, we need to:

1. Ensure we endViewTransition() on the exiting view since the one we
call in onAnimationEnd() wouldn't be executed until after the enter
aniamtion ended.
2. We need to prepare the entering view to be animated in by setting
its alpha to 0, then same as we should if it had gone through createView

RelNote: "Exiting fragments that have their effects reversed now
correctly cancel and restart with the proper entering effect."
Bug: 167092035
Test: FragmentAnimationTest.popReplaceOperationWithAnimation

Change-Id: I622265e9b4ebb210657aac2a5b97dd47061bfd5c

M fragment/fragment/src/androidTest/java/androidx/fragment/app/FragmentAnimationTest.kt
M fragment/fragment/src/main/java/androidx/fragment/app/FragmentStateManager.java

https://android-review.googlesource.com/1442517

il...@google.com <il...@google.com> Oct 27, 2020 11:46PM

Marked as fixed.

ja...@gmail.com <ja...@gmail.com> #4Oct 27, 2020 11:58PM

Any plans soon to release a new fragment beta containing the fix?

il...@google.com <il...@google.com> #5Oct 28, 2020 12:07AM

Re #4 - we're working through our hotlist of issues to confirm that all of them are fixed and only then will be putting out another release. You'd want to use FragmentManager.enableNewStateManager(false) until that point.

Issue 167092035