How to pass props to keyframes in styled-component with react?

Question

I have following code and I want to pass value of y from react component to moveVertically keyframe. Is it possible to do so ?

import React from 'react';
    import styled, {keyframes} from 'styled-components';


    const moveVertically = keyframes`
        0% {
            transform : translateY(0px) 
        }
        100% {
            transform : translateY(-1000px) //I need y here
        }
    `;

    //I can access y in here via props but can't send it above
    const BallAnimation = styled.g`
        animation : ${moveVertically} ${props => props.time}s linear
    `;


    export default function CannonBall(props) {

        const cannonBallStyle = {
            fill: '#777',
            stroke: '#444',
            strokeWidth: '2px',
        };

        return (
            <BallAnimation time = {4} y = {-1000}>
                <circle cx = {0} cy = {0} r="25" style = {cannonBallStyle}/>
            </BallAnimation>
        );
    }

Answer 1

You can make moveVertically a function. Please consider code below:

const moveVertically = (y) => keyframes`
    0% {
        transform : translateY(0px) 
    }
    100% {
        transform : translateY(${y}px)
    }
`;

const BallAnimation = styled.g`
    animation : ${props => moveVertically(props.y)} ${props => props.time}s linear
`;

Here you have y in props of BallAnimation. So you can extract it and pass it to moveVertically function which accepts y value as a parameter.