ReactJS how to render a component only when scroll down and reach it on the page?
I have a react component Data which includes several charts components; BarChart LineChart ...etc.
When Data component starts rendering, it takes a while till receiving the data required for each chart from APIs, then it starts to respond and render all the charts components.
What I need is, to start rendering each chart only when I scroll down and reach it on the page.
Is there any way could help me achieving this??
Answer
You have at least three options how to do that:
Track if component is in viewport (visible to user). And then render it. You can use this HOC https://github.com/roderickhsiao/react-in-viewport
Track ‘y’ scroll position explicitly with https://react-fns.netlify.com/docs/en/api.html#scroll
Write your own HOC using Intersection Observer API https://developer.mozilla.org/en-US/docs/Web/API/Intersection_Observer_API
To render component you may need another HOC, which will return Chart component or ‘null’ based on props it receives.