Prepare the stuff for backgroundColor interpolation

App.tsx

export default function App() {
  const [theme, setTheme] = useState<Theme>('light');

  const rStyle = useAnimatedStyle(() => {
    return {
      backgroundColor: Colors.light.background,
    };
  });

  return (
    <Animated.View style={[styles.container, rStyle]}>
      <Switch
        value={theme === 'dark'}
        onValueChange={(toggled) => {
          setTheme(toggled ? 'dark' : 'light');
        }}
        trackColor={SWITCH_TRACK_COLOR}
        thumbColor={'violet'}
      />
    </Animated.View>
  );
}