Bs-intersection-observer

this package make the bindings for the IntersectionObserver api.

How to install ?

``
npm install bs-intersection-observer --save
`

`bash
yarn add bs-intersection-observer
`

Then add the dependency to you bsconfig.json

`json
"bs-dependencies": [
"bs-intersection-observer"
],
`

How to use it ?

$3

Under the module BsIntersectionObserver, you'll find 2 sub module:

#### Types

Types is pretty obvious, it contains all the types related to the IntersectionObserver. You'll notice that under type there's:

- JsT : Javascript types
- T : Reason types

#### Create

Probably the one you're looking for. Create contains two functions:

- newIntersectionObserver : the direct binding from Js
- intersectionObserver : the IntersectionObserver adapted to Reason with some nice completion (the one you want to call)

$3

`reason
[@bs.val] [@bs.scope "document"]
external querySelector: string => Dom.element = "querySelector";

[@react.component]
let make = () => {
let observer =
BsIntersectionObserver.Create.intersectionObserver(
~cb=
(entries, _) => {
Belt.Array.map(entries, entry =>
if (entry.intersectionRatio > 0.) {
Js.log("Visible element");
} else {
Js.log("Not visible element");
}
)
->ignore;
();
},
~options=None,
);
React.useEffect1(
() => {
let el = querySelector(".hello");
observer.observe(el);
Some(() => observer.unobserve(el));
},
[||],
);

;
};
``