Even if the app is set to dark mode in iOS, there is a problem that the dark mode theme does not apply when switching to the background.

[Jay-flow]

Describe the bug
Even if the app is set to dark mode in iOS, there is a problem that the dark mode theme does not apply when switching to the background.

In the past, I have made full requests on this issue.
Fix the dark mode release from iOS background

I thought I solved this problem at that time, but the frequency of occurrence decreased, but this problem still occurs.
The same problem occurs randomly.
expo/expo#10815 (comment)

This problem is very difficult to solve because it doesn't always happen when you return to the app from the background.

The issue appears to be a bug occurring in iOS and is also registered as an issue in the react-native repository.
facebook/react-native#28525

It is occurring over iOS 13.
facebook/react-native#28525 (comment)
facebook/react-native#28525 (comment)

I tried the following methods as a solution, but they were not solved.

import { Appearance, ColorSchemeName } from 'react-native';
import { useEffect, useRef, useState } from 'react';

export default function useColorScheme(delay = 500): NonNullable<ColorSchemeName> {
  const [colorScheme, setColorScheme] = useState(Appearance.getColorScheme());

  let timeout = useRef<NodeJS.Timeout | null>(null).current;

  useEffect(() => {
    Appearance.addChangeListener(onColorSchemeChange);

    return () => {
      resetCurrentTimeout();
      Appearance.removeChangeListener(onColorSchemeChange);
    };
  }, []);

  function onColorSchemeChange(preferences: Appearance.AppearancePreferences) {
    resetCurrentTimeout();

    timeout = setTimeout(() => {
      setColorScheme(preferences.colorScheme);   // <-- the preferences.colorScheme is light.
    }, delay);
  }

  function resetCurrentTimeout() {
    if (timeout) {
      clearTimeout(timeout);
    }
  }

  return colorScheme as NonNullable<ColorSchemeName>;
}

or

 const initAppearanceListener = () => {
    const listener: Appearance.AppearanceListener = ({ colorScheme } /* <-- ignore */) => {
      setColorScheme(Appearance.getColorScheme());
    };
    Appearance.addChangeListener(listener);
    return () => Appearance.removeChangeListener(listener);
  };

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To Reproduce
Steps to reproduce the behavior:

1. Set the iOS device to dark mode.
2. Turn on the app that applied the theme of doboo-ui.
3. Switch to the background.
4. I'm coming back to the app.

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Expected behavior
The dark theme should be maintained when returning the app from the background to the foreground.

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Screenshots

140264579-51a3fc65-01ab-4df6-adc4-52ac95b3cdba.mov

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Smartphone (please complete the following information):

• Device: iPhone
• OS: iOS 14.8.1
• Version: 0.1.48

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Additional context
N/A

[hyochan]

Looks like this is resolved~!

[efstathiosntonas]

@hyochan can you please explain how this was solved? Thanks