Apperance.getColorScheme() returns incorrect value if app opened in background (e.g. using Healthkit.HKObserverQuery)

[walterholohan]

Description

When using a background process like Healthkit.HKObserverQuery it will wake up the app in the background to process new activities in HealthKit. When this happens Apperance.getColorScheme() will return 'light' even if the system color scheme is 'dark'

Steps to reproduce

1. Use https://github.com/kingstinct/react-native-healthkit to enable enableBackgroundDelivery i.e. HealthKit.enableBackgroundDelivery(HKWorkoutTypeIdentifier, HKUpdateFrequency.immediate)
2. app has been force closed
3. record a workout an Apple Workouts app on Apple Watch
4. save the workout
5. the app will open in the background and process the new workout
6. open the app after a couple of minutes, then the app will open in Light mode i.e. Appearance.getColorScheme() will be 'light'

React Native Version

0.74.3

Affected Platforms

Runtime - iOS

Output of npx react-native info

System:
  OS: macOS 14.5
  CPU: (10) arm64 Apple M1 Pro
  Memory: 137.53 MB / 16.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 18.19.1
    path: ~/.nvm/versions/node/v18.19.1/bin/node
  Yarn:
    version: 1.22.19
    path: /opt/homebrew/bin/yarn
  npm:
    version: 10.2.4
    path: ~/.nvm/versions/node/v18.19.1/bin/npm
  Watchman:
    version: 2024.01.22.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.15.2
    path: /Users/walterholohan/.rbenv/shims/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 23.4
      - iOS 17.4
      - macOS 14.4
      - tvOS 17.4
      - visionOS 1.1
      - watchOS 10.4
  Android SDK: Not Found
IDEs:
  Android Studio: 2023.1 AI-231.9392.1.2311.11330709
  Xcode:
    version: 15.3/15E204a
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 11.0.12
    path: /usr/local/opt/openjdk@11/bin/javac
  Ruby:
    version: 3.0.4
    path: /Users/walterholohan/.rbenv/shims/ruby
npmPackages:
  "@react-native-community/cli": Not Found
  react:
    installed: 18.2.0
    wanted: 18.2.0
  react-native:
    installed: 0.74.3
    wanted: 0.74.3
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: false
iOS:
  hermesEnabled: true
  newArchEnabled: false

Stacktrace or Logs

Appearance.getColorScheme() will return 'light' when the app opens

Reproducer

I created a new native module in iOS to test if it was a iOS or RN bug. The below code will return the correct value so hence its a bug with RN

import UIKit

@objc(RbAppearance)
class RbAppearance: NSObject {

  @objc(getColorScheme:withRejecter:)
  func getColorScheme(resolve:RCTPromiseResolveBlock,reject:RCTPromiseRejectBlock) -> Void {
    let colorScheme = UITraitCollection.current.userInterfaceStyle
      
      switch colorScheme {
          case .dark:
              resolve("dark")
          case .light:
              resolve("light")
          @unknown default:
              resolve("unknown")
          }
  }
}

Screenshots and Videos

No response

[react-native-bot]

⚠️	Missing Reproducible Example
ℹ️	We could not detect a reproducible example in your issue report. Please provide either: If your bug is UI related: a Snack If your bug is build/update related: use our Reproducer Template. A reproducer needs to be in a GitHub repository under your username.

[react-native-bot]

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ℹ️	We could not find or parse the version number of React Native in your issue report. Please use the template, and report your version including major, minor, and patch numbers - e.g. 0.70.2

[react-native-bot]

⚠️	Missing Reproducible Example
ℹ️	We could not detect a reproducible example in your issue report. Please provide either: If your bug is UI related: a Snack If your bug is build/update related: use our Reproducer Template

[react-native-bot]

⚠️	Add or Reformat Version Info
ℹ️	We could not find or parse the version number of React Native in your issue report. Please use the template, and report your version including major, minor, and patch numbers - e.g. 0.70.2

[RodolfoGS]

I have the same issue but with expo-background-fetch, looks like that is the same bug.
@walterholohan, did you tested the @zhongwuzw's PR?

[zhongwuzw]

@RodolfoGS Yeah, you can try that fix.

[walterholohan]

Thanks all, yep will try that and use as a patch.