react-native-scalable-analog-clock/helpers/hooks.ts

Scalable analog clock face.

import React, { useState, useEffect, useRef } from "react"

// From Dan Abramov https://overreacted.io/making-setinterval-declarative-with-react-hooks/
export function useInterval(callback, delay) {
    const savedCallback = useRef(null)

    // Remember the latest callback.
    useEffect(() => {
        savedCallback.current = callback
    }, [callback])

    // Set up the interval.
    useEffect(() => {
        function tick() {
            savedCallback.current()
        }
        if (delay !== null) {
            let id = setInterval(tick, delay)
            return () => clearInterval(id)
        }
    }, [delay])
}