feat: add support for fallbackInView

[thebuilder]

This is solution for #495 that adds support for a fallbackInView value.

You can set the fallback globally:

import { defaultFallbackInView } from 'react-intersection-observer';
defaultFallbackInView(true); // or 'false'

You can also define the fallback locally on useInView or <InView> as an
option. This will override the global fallback value.

import React from 'react';
import { useInView } from 'react-intersection-observer';

const Component = () => {
  const { ref, inView, entry } = useInView({
    fallbackInView: true,
  });

  return (
    <div ref={ref}>
      <h2>{`Header inside viewport ${inView}.`}</h2>
    </div>
  );
};

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit d30d0e9:

Sandbox	Source
useInView	Configuration
InView render props	Configuration
InView plain children	Configuration

[vercel]

This pull request is being automatically deployed with Vercel (learn more).
To see the status of your deployment, click below or on the icon next to each commit.

🔍 Inspect: https://vercel.com/the-builder/react-intersection-observer/HZi7fsP5Jj4WmiimDeKrKUcst44v
✅ Preview: https://react-intersection-observer-git-feature-fall-f87a33-the-builder.vercel.app

[dale-french]

Thanks for this 🙌

Any idea when this will get released?

[thebuilder]

Just want to make sure it's the right approach. :)

[thebuilder]

🎉 This PR is included in version 8.33.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀