SavedStateRegistryOwner should describe the implementing classes' responsibilities [228887344]

Fixed

Bug

Status Update

No update yet.

Description

il...@google.com

created issue #1

Apr 11, 2022 10:47PM

Component used: SavedState

Version used: 1.2.0-alpha02

The docs on SavedStateRegistryOwner do not explain the responsibilities and contract that the owner has on how they should implement SavedStateRegistryOwner or when they should call the methods on SavedStateRegistryController.

Ideally the class docs should talk through:

That performAttach() should be called only once, usually as part of the initialization of the owner. It must be called on the main thread.
That performRestore should be called unconditionally (either with null if no state is being restored or the Bundle of state to restore) either directly before moving the Lifecycle to CREATED or as part of a LifecycleObserver that is added as part of the initialization of the owner.
When the state of the owner is saved, performSave() must be called. The Bundle saved there should be what is later sent to performRestore().

Comments

il...@google.com <il...@google.com> Apr 14, 2022 04:58PM

Assigned to cl...@google.com.

cl...@google.com <cl...@google.com> Apr 14, 2022 04:59PM

Accepted by cl...@google.com.

ap...@google.com <ap...@google.com> #2Apr 19, 2022 10:44PM

Marked as fixed.

A couple of questions:

1. Have you saw crash in real device or only in simulators?
2. Do you use dynamic feature for language ID?

le...@gmail.com <le...@gmail.com> #3Oct 21, 2022 02:20AM

Tested on Android 12 Emulator with custom executor, but cannot repro this issue.

le...@gmail.com <le...@gmail.com> #4Oct 21, 2022 02:21AM

Second crash in the description is from a real device. Experienced it myself on two different Xiaomi phones, plus lots of crashes from users in the Google Play console.
Dynamic features are not used in the application.

As a wild guess, I have downgraded build tools from 31.0.0 to 30.0.3, compileSdk from 31 to 30, and moved all work with Language ID to the service in a separate process (just to be sure that crash can kill secondary process instead of main). This combination is in beta for 2 days by now and I don't see any SIGSEGV crashes.

le...@gmail.com <le...@gmail.com> #5Oct 21, 2022 02:22AM

Hmm, I feel the crash might be something related to separate/secondary process.

I also changed compileSdk and targetSDK to 31 but still cannot repro this issue.

le...@gmail.com <le...@gmail.com> #6Oct 21, 2022 02:22AM

On the contrary, there was no separate process before, when crashes started.

In the new build (with the aforementioned changes) I can see SIGSEGV crash, but only one instead of dozens and it has a bit different backtrace:

signal 11 (SIGSEGV), code 1 (SEGV_MAPERR)
liblanguage_id_jni.so (offset 0x11e000)

backtrace:
  #00  pc 000000000003c7c0  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 000000000003b960  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 000000000003bb48  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 000000000003bafc  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000036c98  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000032714  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000031cac  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/split_config.arm64_v8a.apk!lib/arm64-v8a/liblanguage_id_jni.so (offset 0x11e000)
  #00  pc 0000000000057438  /data/app/azagroup.reedy-mF7zTu2bv_ELlbFArwNgqA==/oat/arm64/base.odex (offset 0x57000)