LocalConfiguration can become out of sync from the Activity configuration [247143459]

Bug

Status Update

No update yet.

Description

va...@google.com

created issue #1

Sep 16, 2022 08:42PM

Conditions:

API 32 or API 33
An activity that is not opting out of screen size related config changes (android:configChanges is empty or only has unrelated entries)
No resources that differ between the corresponding window sizes

When resizing the activity in multi-window mode under those conditions, there are cases where:

the Activity is not recreated
Activity.onConfigurationChanged is not called
View.onConfigurationChanged is not called

Because LocalConfiguration.current is driven by View.onConfigurationChanged at the moment, this results in LocalConfiguration.current not updating, and getting out of sync with the underlying Activity configuration.

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        setContent {
            LaunchedEffect(Unit) {
                while(true) {
                    delay(1000)
                    Log.d("vanyo", "activity configuration: ${resources.configuration}")
                }
            }
            Log.d("vanyo", "LocalConfiguration ${LocalConfiguration.current}")
        }
    }
}

In the above, constantly polling for the Activity configuration reveals that it is changing (when resizing happens), but LocalConfiguration.current does not update.

This particularly matters for material3-window-size-class, since the LocalConfiguration.current is used as a signal to relcalculate the window metrics

Workarounds or potential fixes:

Find an alternate signal to update LocalConfiguration.current to the current configuration, since View.onConfigurationChanged may not always be called
Specify android:configChanges for the screen size changes, to ensure that View.onConfigurationChanged is called
Add resources that intentionally influence the "buckets" to ensure that the Activity is recreated

Comments

va...@google.com <va...@google.com> #2Sep 16, 2022 09:56PM

Attached reproducing video of an app using calculateWindowSizeClass and LocalConfiguration:

On the second time resizing to be 50%/50% from smaller, the displayed configuration is incorrect.

device-2022-09-16-145443.webm

9.9 MB

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lp...@google.com <lp...@google.com> #3Sep 20, 2022 04:38PM

When resizing the activity in multi-window mode under those conditions, there are cases where:

the Activity is not recreated Activity.onConfigurationChanged is not called View.onConfigurationChanged is not called

Is this just for 33 / is there a framework bug filed? The amount of broken things in configuration land we already had to workaround in Compose is a bit untenable. It seems like we are missing a lot of test coverage in the platform to avoid these issues hitting us in the future

lp...@google.com <lp...@google.com> #4Sep 20, 2022 04:39PM

In any case this seems like more ammunition for us to push more strongly on 'pure-compose apps should always opt out of configuration changes'

va...@google.com <va...@google.com> #5Sep 20, 2022 04:56PM

Yes, API 33 introduced this behavior, (internal) platform bug is here: b/247013643

va...@google.com <va...@google.com> #6Sep 21, 2022 09:55PM

I was incorrect, this is also reproducible on API 32 as well. Not reproducible on API 31.

Message last modified on Sep 21, 2022 09:55PM

js...@google.com <js...@google.com> #7Sep 24, 2022 10:26AM

Adam/Louis, how do we want to handle this one? Is there someone on platform who should take this, or since API 32 is already out in the wild maybe this should go to devrel to push more strongly on 'pure-compose apps should always opt out of configuration changes'.

ar...@gmail.com <ar...@gmail.com> #8Nov 6, 2022 05:45AM

Comment has been deleted.

Message last modified on Jan 19, 2023 04:47PM

te...@gmail.com <te...@gmail.com> #9Jun 28, 2024 09:52AM

I'm having issues on pre-33 api levels on a pure compose app (has all configChanges added in the manifest file) pared with AppCompatActivity just for multi language support. When changing the language I'm using AppCompatDelegate.setApplicationLocales(compat) which calls onConfigurationChanged on the activity. LocalConfiguration changes to the new configuration on 33+ but remains the same on pre-33. Workaround that i've found is calling if (Build.VERSION.SDK_INT < 33) contentView.dispatchConfigurationChanged(newConfig) in onConfigurationChanged. I'm guessing it's a compose issue since activity wise everything works as expected.

va...@google.com <va...@google.com> #10Jun 28, 2024 03:47PM

#comment9 sounds like b/321896385, which is also related to LocalConfiguration but a separate issue.

te...@gmail.com <te...@gmail.com> #11Jun 28, 2024 04:17PM

Thanks for the heads up, I've tried to find a related issue but only managed to find this one after a brief search.

pe...@gmail.com <pe...@gmail.com> #12Oct 26, 2024 12:34PM

pe...@gmail.com <pe...@gmail.com> #13Oct 26, 2024 12:35PM