ViewPager2 does not snap to the current position when device is rotated (partially stuck) [175796502]

Bug

Status Update

No update yet.

Description

[Deleted User]

created issue #1

Dec 17, 2020 05:50PM

Component used: ViewPager2
Version used: 1.0.0
Devices/Android versions reproduced on:
1) Google Pixel 4 XL (Android 10), Xiaomi Redmi S2 (Android 8.1)

ViewPager2 does not snap to the current position when device is rotated and when the activity has "android:configChanges="keyboardHidden|orientation|screenSize" set in the Manifest so that the activity and views in it are not recreated.
I expect the ViewPager2 to snap to its current position when it is re-measured and re-laid out.

I attached a video demonstrating the issue and the source code of the project.

Thanks in advance.

ViewPager2Bug.zip

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before_rotation.png

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after_rotation.png

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20201217_204354.mp4

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Comments

[Deleted User] <[Deleted User]> #2Dec 17, 2020 05:52PM

Could you look into it @christofferqa?

The issue is with this class:

class MySpi : Spi {
    @Volatile
    private var myApi: Api? = null

    // Incorrectly rewritten to return null;
    override fun createApi(): Api {
        return myApi ?: synchronized(this) {
            myApi ?: MyApi().also { myApi = it }
        }
    }
}

The error seems to be that the ArgumentPropagator believes that the fieldState of myApi is ExactDynamicType(@NotNull MyApi) while it should be ExactDynamicType(@Nullable MyApi)

It then removes the first branch (assuming myApi is not null):

return myApi ?: synchronized(this) {
            myApi ?: MyApi().also { myApi = it }
        }

is rewritten into:

return myApi

And then it eventually concludes that myApi is always null, replacing the code by

return null

The ArgumentPropagatorCodeScanner analyzes the assignment myApi = it and correctly set join the state to ExactDynamicType(@NotNull MyApi)

However the ArgumentPropagator fails to understand that myApi can be read before being written in the method, relying on the default null value, so it fails to join null to the dynamic type.

on...@gmail.com <on...@gmail.com> #3Feb 18, 2021 06:33PM

Yes I can take a look. Would it be possible for you to add a regression test of this issue?

nd...@gmail.com <nd...@gmail.com> #4May 6, 2021 10:47PM

Project: r8
Branch: main
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101407

Reproduce field propagation issue with ServiceLoader

Expand for full commit details

Reproduce field propagation issue with ServiceLoader 
 
Bug: b/389737060 
Change-Id: Id850448f68b999194bc0380dfca625f4f68bc31b

Files:

A src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: 6ba9af34b15f2a0d3fe356f6e7a5a4071128aed9
Date: Wed Feb 12 09:31:01 2025

jg...@google.com <jg...@google.com> #5May 7, 2021 12:01PM

Project: r8
Branch: main
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101408

Account for ServiceLoaders in field value propagation

Expand for full commit details

Account for ServiceLoaders in field value propagation 
 
Fixes: b/389737060 
Change-Id: Ide438a8e1b0541f3ce2385087f06f8b9909ab3c5

Files:

M src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/DefaultFieldValueJoiner.java
M src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: 692fff07b70f6ee5ac520b179aed5e125a0d4848
Date: Wed Feb 12 09:34:04 2025

jg...@google.com <jg...@google.com> #6May 7, 2021 02:09PM

Project: r8
Branch: 8.9
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101512

Account for ServiceLoaders in field value propagation

Expand for full commit details

Account for ServiceLoaders in field value propagation 
 
Fixes: b/389737060 
Change-Id: Ide438a8e1b0541f3ce2385087f06f8b9909ab3c5

Files:

M src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/DefaultFieldValueJoiner.java
M src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: 76cad195cf43c16aa9e7b0203e51662036587e71
Date: Thu Feb 13 10:33:29 2025

jk...@gmail.com <jk...@gmail.com> #7May 30, 2021 08:36AM

Project: r8
Branch: 8.9
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101522

Version 8.9.28

Expand for full commit details

Version 8.9.28 
 
Bug: b/389737060 
Change-Id: I42c8d3194dc053e3a16eef8ea1c4b3aced6752d6

Files:

M src/main/java/com/android/tools/r8/Version.java

Hash: 668c1778e857c1bc8e3f9308a65ddc01a6c14898
Date: Thu Feb 13 10:33:34 2025

my...@gmail.com <my...@gmail.com> #8Jun 8, 2021 11:54PM

Project: r8
Branch: 8.9
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101511

Reproduce field propagation issue with ServiceLoader

Expand for full commit details

Reproduce field propagation issue with ServiceLoader 
 
Bug: b/389737060 
Change-Id: Id850448f68b999194bc0380dfca625f4f68bc31b

Files:

A src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: a76d3e8637b5280dcc972ed9fabc74bb503cc30c
Date: Thu Feb 13 10:33:24 2025

my...@gmail.com <my...@gmail.com> #9Jun 8, 2021 11:58PM

Project: r8
Branch: 8.8
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101513

Reproduce field propagation issue with ServiceLoader

Expand for full commit details

Reproduce field propagation issue with ServiceLoader 
 
Bug: b/389737060 
Change-Id: Id850448f68b999194bc0380dfca625f4f68bc31b

Files:

A src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: a63678f7ebb3321af74c9846be9c851e4da78e4f
Date: Thu Feb 13 10:33:55 2025

me...@gmail.com <me...@gmail.com> #10Jun 19, 2021 10:58AM

Project: r8
Branch: 8.8
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101514

Version 8.8.35

Expand for full commit details

Version 8.8.35 
 
Bug: b/389737060 
Change-Id: I2361f77b42b529f2cbdfbf60fbe4a95e405ba716

Files:

M src/main/java/com/android/tools/r8/Version.java

Hash: d280891c805561bc120f5f96841b50353e74edfe
Date: Thu Feb 13 10:34:06 2025

jk...@gmail.com <jk...@gmail.com> #11Jul 2, 2021 09:44AM

Project: r8
Branch: 8.8
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101523

Account for ServiceLoaders in field value propagation

Expand for full commit details

Account for ServiceLoaders in field value propagation 
 
Fixes: b/389737060 
Change-Id: Ide438a8e1b0541f3ce2385087f06f8b9909ab3c5

Files:

M src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/DefaultFieldValueJoiner.java
M src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: 05dd13d906b60efdf03caea7067dedf67b7c6a2e
Date: Thu Feb 13 10:34:00 2025

su...@gmail.com <su...@gmail.com> #12Aug 2, 2021 10:36AM

Project: r8
Branch: 8.7
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101540

Account for ServiceLoaders in field value propagation

Expand for full commit details

Account for ServiceLoaders in field value propagation 
 
Fixes: b/389737060 
Change-Id: Ide438a8e1b0541f3ce2385087f06f8b9909ab3c5

Files:

M src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/DefaultFieldValueJoiner.java
M src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: d7dcc9001453052f772056337d3c120dba34fc46
Date: Thu Feb 13 10:34:31 2025

en...@gmail.com <en...@gmail.com> #13Oct 1, 2021 09:57AM

Project: r8
Branch: 8.7
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101541

Version 8.7.35

Expand for full commit details

Version 8.7.35 
 
Bug: b/389737060 
Change-Id: Icfb60f565b329600b5f167a496a39a61ebff9ea6

Files:

M src/main/java/com/android/tools/r8/Version.java

Hash: 1be71bdf4455bbc565502b4c3bbbae64608c57a6
Date: Thu Feb 13 10:34:38 2025

jg...@google.com <jg...@google.com> #14Oct 7, 2021 10:39AM

Status: New (reopened)

Project: r8
Branch: 8.7
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101515

Reproduce field propagation issue with ServiceLoader

Expand for full commit details

Reproduce field propagation issue with ServiceLoader 
 
Bug: b/389737060 
Change-Id: Id850448f68b999194bc0380dfca625f4f68bc31b

Files:

A src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: 7272540b4f7850ef22543defc221660359704ea2
Date: Thu Feb 13 10:34:26 2025

jg...@google.com <jg...@google.com> #15Oct 7, 2021 10:41AM

Project: r8
Branch: 8.9
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101512

Account for ServiceLoaders in field value propagation

Expand for full commit details

Account for ServiceLoaders in field value propagation 
 
Fixes: b/389737060 
Change-Id: Ide438a8e1b0541f3ce2385087f06f8b9909ab3c5

Files:

M src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/DefaultFieldValueJoiner.java
M src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: 76cad195cf43c16aa9e7b0203e51662036587e71
Date: Thu Feb 13 10:33:29 2025

ni...@gmail.com <ni...@gmail.com> #16Nov 24, 2021 11:25AM

Project: r8
Branch: 8.9
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101511

Reproduce field propagation issue with ServiceLoader

Expand for full commit details

Reproduce field propagation issue with ServiceLoader 
 
Bug: b/389737060 
Change-Id: Id850448f68b999194bc0380dfca625f4f68bc31b

Files:

A src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: a76d3e8637b5280dcc972ed9fabc74bb503cc30c
Date: Thu Feb 13 10:33:24 2025

on...@gmail.com <on...@gmail.com> #17Nov 29, 2021 11:26AM

This should now be fixed in R8 8.7.36, 8.8.36 and 8.9.28.

se...@digitecgalaxus.ch <se...@digitecgalaxus.ch> #18Dec 12, 2022 07:29AM

Project: r8
Branch: 8.8
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101518

Version 8.8.36

Expand for full commit details

Version 8.8.36 
 
Bug: b/389737060 
Change-Id: I9ac9a6eda36030b2569bf6839f9b55257f0d2888

Files:

M src/main/java/com/android/tools/r8/Version.java

Hash: d228eeda266e288da18698a2fa464fc97b0303c3
Date: Thu Feb 13 12:31:37 2025

Message last modified on Dec 12, 2022 07:30AM

an...@nexgeniots.com <an...@nexgeniots.com> #19Jun 8, 2023 05:49PM

Project: r8
Branch: 8.8
Author: Christoffer Adamsen <christofferqa@google.com>
Link: https://r8-review.googlesource.com/101547

Fix call to addDataResources in test

Expand for full commit details

Fix call to addDataResources in test 
 
This was added in 8.9. 
 
Bug: b/389737060 
Change-Id: I604550f0c0034256f71c03874eeb4798f7079f18

Files:

M src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java

Hash: 58502e8fa34f0abe33a254671faf1b74e0668c86
Date: Thu Feb 13 12:30:57 2025

Issue 175796502

Description

Issue summary

Comments

[Deleted User] <[Deleted User]> #2Dec 17, 2020 05:52PM

on...@gmail.com <on...@gmail.com> #3Feb 18, 2021 06:33PM

nd...@gmail.com <nd...@gmail.com> #4May 6, 2021 10:47PM

jg...@google.com <jg...@google.com> #5May 7, 2021 12:01PM

jg...@google.com <jg...@google.com> #6May 7, 2021 02:09PM

jk...@gmail.com <jk...@gmail.com> #7May 30, 2021 08:36AM

my...@gmail.com <my...@gmail.com> #8Jun 8, 2021 11:54PM

my...@gmail.com <my...@gmail.com> #9Jun 8, 2021 11:58PM

me...@gmail.com <me...@gmail.com> #10Jun 19, 2021 10:58AM

jk...@gmail.com <jk...@gmail.com> #11Jul 2, 2021 09:44AM

su...@gmail.com <su...@gmail.com> #12Aug 2, 2021 10:36AM

en...@gmail.com <en...@gmail.com> #13Oct 1, 2021 09:57AM

jg...@google.com <jg...@google.com> #14Oct 7, 2021 10:39AM

jg...@google.com <jg...@google.com> #15Oct 7, 2021 10:41AM

ni...@gmail.com <ni...@gmail.com> #16Nov 24, 2021 11:25AM

on...@gmail.com <on...@gmail.com> #17Nov 29, 2021 11:26AM

se...@digitecgalaxus.ch <se...@digitecgalaxus.ch> #18Dec 12, 2022 07:29AM

an...@nexgeniots.com <an...@nexgeniots.com> #19Jun 8, 2023 05:49PM

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