useAtomCallback

引用: https://github.com/pmndrs/jotai/issues/60

使用

useAtomCallback(
  callback: (get: Getter, set: Setter, arg: Arg) => Result
): (arg: Arg) => Promise<Result>

这个 hook 允许与原子进行命令式交互。 它需要一个像原子写函数一样工作的回调函数， 并返回一个返回承诺的函数。

传递给 hook 的回调必须是稳定的（应该用 useCallback 包装）。

示例

import { useEffect, useState, useCallback } from "react";
import { Provider, atom, useAtom } from "jotai";
import { useAtomCallback } from "jotai/utils";

const countAtom = atom(0);

const Counter = () => {
  const [count, setCount] = useAtom(countAtom);
  return (
    <>
      {count} <button onClick={() => setCount((c) => c + 1)}>+1</button>
    </>
  );
};

const Monitor = () => {
  const [count, setCount] = useState(0);
  const readCount = useAtomCallback(
    useCallback((get) => {
      const currCount = get(countAtom);
      setCount(currCount);
      return currCount;
    }, [])
  );
  useEffect(() => {
    const timer = setInterval(async () => {
      console.log(await readCount());
    }, 1000);
    return () => {
      clearInterval(timer);
    };
  }, [readCount]);
  return <div>current count: {count}</div>;
};

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