VerticalGridView leaking views in various Leanback Fragments [171909417]

Fixed

Bug

Status Update

No update yet.

Description

mc...@gmail.com

created issue #1

Oct 28, 2020 08:24PM

Component used: androidx.leanback:leanback:1.1.0-alpha05

RowsSupportFragment will be used in the following example, but the issue is also present in other fragments.

App uses single activity architecture with Androidx Navigation component. RowsSupportFragment is declared in the fragment layout xml via a FragmentContainerView using the android:name attribute.
When navigating away and the current fragment is placed in the backstack, the RowsSupportFragment instance is retained and re-used, and leaks the VerticalGridView, and by extension the entire fragment view hierarchy, that should have been destroyed.

When the adapter is set on the RowsSupportFragment, the VerticalGridView's adapter is also set via mVerticalGridView.setAdapter(mBridgeAdapter), which registers the view as an observer inside mBridgeAdapter. In BaseRowSupportFragment's onDestroyView, the mVerticalGridView reference is nulled. However, this is insufficient as mBridgeAdapter still holds a reference to the view as an observer. The VerticalGridView's adapter should also be nulled to clear this reference.

A workaround is by overriding RowsSupportFragment and manually nulling the VerticalGridView's adapter in onDestroyView. But this does not work for something like VerticalGridSupportFragment which does not expose the internal VerticalGridView.

Comments

da...@google.com <da...@google.com> Nov 19, 2020 10:51PM

Accepted by da...@google.com.

ap...@google.com <ap...@google.com> #2Nov 20, 2020 03:50AM

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?

ap...@google.com <ap...@google.com> #3Nov 21, 2020 12:10AM

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

ap...@google.com <ap...@google.com> #4Nov 23, 2020 06:32PM

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.

ap...@google.com <ap...@google.com> #5Nov 23, 2020 07:15PM

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.

ap...@google.com <ap...@google.com> #6Nov 24, 2020 07:26PM

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)

ap...@google.com <ap...@google.com> #7Nov 25, 2020 12:06AM

FYI, ML Kit launched a new language ID SDK in the latest release, which uses a new language ID model. https://developers.google.com/ml-kit/release-notes#august_11_2021

Could you try the new SDK version(17.0.0) to check if you can still repro this native crash? Thanks!

ap...@google.com <ap...@google.com> #8Dec 3, 2020 07:33PM

Thank you, I'll try it and check.

da...@google.com <da...@google.com> Dec 3, 2020 09:28PM

Marked as fixed.

ma...@gmail.com <ma...@gmail.com> #9Dec 12, 2020 01:31AM

Hello. I have similar experience.

I'm using mlkit-language 16.1.1
I didnot meet this error until using AGP 4.2
I can get this error since using AGP 7.0
This error raised on Release build only(minimized by R8)
This error raised without obfuscation.

th...@gmail.com <th...@gmail.com> #10May 9, 2021 04:44PM

Also I found there is a post which presents same issue on stackoverflow.

https://stackoverflow.com/questions/68832304/mlkit-translate-sdk-crashes-in-release-build