useColorScheme.jsx

import { useColorScheme } from 'react-native'

const styles = StyleSheet.create({
  titleLight: {
    color: 'black'
  },
  titleDark: {
    color: 'white'
  }
})

const Example = () => {
  const colorScheme = useColorScheme()
  const isDark = colorScheme === 'dark'
  
  return (
    <Text style={isDark ? styles.titleDark : styles.titleLight}>
      Some text...
    </Text>
  )
}