Easy problem : Trying to change content when button is press React native

Question

I'm actualy coding a mobile app for school and I have problems when try to change content of a Text when I'm pressing a TouchableOpacity button.

I want that : When I press the button (actualy a text button) it change the content of a Text by the actual text of the button (imagine menu where you have to chose an app ex: discord/yammer etc... and when you press on the app you want it change the actual '...' by the name of the app)

visual to help you :

To do this I wrote this :

const PopupMenuSelect = () => {
    const [visible, setVisible] = useState(false);
    const scale = useRef(new Animated.Value(0)).current;
    let content = '...';
    const options = [
        {
            title: 'Spotify',
            icon: 'spotify',
            action: () => content = options.title,
        },
        {
            title: 'Yammer',
            icon: 'yammer',
            action: () => content === options.title,
        },
        {
            title: 'Trello',
            icon: 'trello',
            action: () => content === options.title,
        },
        {
            title: 'Twitter',
            icon: 'twitter',
            action: () => content = options.title,
        },
        {
            title: 'Discord',
            icon: 'discord',
            action: () => content === options.title,
        },
        {
            title: 'Outlook',
            icon: 'mail-bulk',
            action: () => content === options.title,
        },
    ]
    function resizeBox(to){
        to === 1 && setVisible(true);
        Animated.timing(scale,{
            toValue:to,
            useNativeDriver:true,
            duration:200,
            easing: Easing.linear,
        }).start(() => to === 0 && setVisible(false));
    }
    return (
        <>
            <TouchableOpacity onPress={() => resizeBox(1)}>
                <Text style={[style.subtext, { color: layouts.secondary }]}>{content}</Text>
            </TouchableOpacity>
            <Modal transparent visible={visible}>
                <SafeAreaView style={{ flex: 1 }} onTouchStart={() => resizeBox(0)}>
                    <Animated.View 
                    style={[
                        style.popUp,
                            { opacity: scale.interpolate({ inputRange: [0, 1], outputRange:[0, 1]}) },
                            { transform: [{ scale }]},
                        ]}
                    >
                        {options.map((op, i) => (
                            <TouchableOpacity style={[style.option, { borderBottomWidth: i === options.length - 1 ? 0 : 1 }]} key={i} onPress={op.action}>
                                <Text style={{fontFamily: "Title-Font", fontSize: 15}}>{op.title}</Text>
                                <FontAwesome5 name={op.icon} size={26} color={'black'} style={{marginLeft: 10}}/>
                            </TouchableOpacity>
                        ))}
                    </Animated.View>
                </SafeAreaView>
            </Modal>
        </>
    )
}

export default PopupMenuSelect;

I create a let variable named 'content' = '...' and I set the action of the button to replace the content by the title of the 'option'

like this :

            action: () => content = options.title,

but it didn't work, that didn't change the content when I press the button (Spotify or something).

Thanks a lot in advance guys, love u

Answer 1

The view only re-renders when a state changes, content is a let. You could solve the problem by changing the content to a state. Change the content to the option title when onPress is fired.

const [content, setContent] = useState('')

...

<TouchableOpacity ... onPress={() => setContent(op.title)}>
  ...
</TouchableOpacity>

Another option, if you really want to handle it from the action in the array, could be to pass the option into the function

const options = [
  {
    title: 'Spotify',
    icon: 'spotify',
    action: (option) => setContent(option.title),
  },
  ....
];

...

<TouchableOpacity ... onPress={() => op.action(op)}>
  ...
</TouchableOpacity>