Reset signals when prop value changes

How can I reset the showFront state of Card when Card's props.data changes?

type CardProps = {
    data: Card
}

const Card = (props: CardProps) => {
    const [showFront, setShowFront] = createSignal<boolean>(true)
    // ...
}

type CardProps = {
    data: Card
}

const Card = (props: CardProps) => {
    const [showFront, setShowFront] = createSignal<boolean>(true)
    // ...
}

return (
    <Container>
        <Card data={currentCard()} />
        <!-- buttons to navigate between cards -->
    </Container>
)

return (
    <Container>
        <Card data={currentCard()} />
        <!-- buttons to navigate between cards -->
    </Container>
)

5 Replies

Mr Void•2mo ago

Currently resetting this way, is there a better way? :

const [currentCardId, setCurrentCardId] = createSignal<string | null>(null)

const Card = () => {
    // ...
    createEffect(() => {
        if (currentCardId() === null) {
            setCurrentCardId(props.data.id)
        } else if(currentCardId() !== props.data.id) {
            batch(() => {
                setCurrentCardId(props.data.id)
                setShowFront(true)
            })
        }
    })

   // ...
}

const [currentCardId, setCurrentCardId] = createSignal<string | null>(null)

const Card = () => {
    // ...
    createEffect(() => {
        if (currentCardId() === null) {
            setCurrentCardId(props.data.id)
        } else if(currentCardId() !== props.data.id) {
            batch(() => {
                setCurrentCardId(props.data.id)
                setShowFront(true)
            })
        }
    })

   // ...
}

foolswisdom•2mo ago

Generally speaking, what you're looking for is a writeableMemo. I believe #solid-primitives has an implementation you can use

Mr Void•2mo ago

I tried the following and doesn't cause re-rendering for all Card components, is this a decent solution or should I use createWritableMemo ?

const Card = (props) => {
    let prevId = props.data.id;

    createEffect(() => {
        if (prevId !== props.data.id) {
            prevId = props.data.id
            setShowFront(true)
        }
    }
}

const Card = (props) => {
    let prevId = props.data.id;

    createEffect(() => {
        if (prevId !== props.data.id) {
            prevId = props.data.id
            setShowFront(true)
        }
    }
}

foolswisdom•2mo ago

Nah, I didn't quite realize your use case Not quite a fit Anyway, if it works it works

NitonFx•2mo ago

i mean one should not read a prop in the main body of the component afaik wouldn't this be cleaner

const Card = (props) => {
    createEffect(on(props.data, (_) => {
        setShowFront(true)
    }))
}

const Card = (props) => {
    createEffect(on(props.data, (_) => {
        setShowFront(true)
    }))
}

Gaming

Programming

Reset signals when prop value changes