Reactjs 与React一起使用时未调用requestAnimationFrame回调
我试图用react组件包装画布组件,并设置requestAnimationFrame,以便能够在画布上绘制动画 我有一个简单的组件,它试图简单地画一个圆:Reactjs 与React一起使用时未调用requestAnimationFrame回调,reactjs,animation,requestanimationframe,Reactjs,Animation,Requestanimationframe,我试图用react组件包装画布组件,并设置requestAnimationFrame,以便能够在画布上绘制动画 我有一个简单的组件,它试图简单地画一个圆: import * as React from "react"; import { useLayoutEffect, useRef } from "react"; export interface Props {} export const Loop: React.FC<Props> =
import * as React from "react";
import { useLayoutEffect, useRef } from "react";
export interface Props {}
export const Loop: React.FC<Props> = () => {
const cv = useRef<HTMLCanvasElement>(null);
const oldTimestamp = useRef<number>(0);
useLayoutEffect(() => {
let animationID = 0;
console.log("USEEFFECT");
const loop = (timestamp: number) => {
let secondsPassed = (timestamp - oldTimestamp.current) / 1000;
secondsPassed = Math.min(secondsPassed, 0.1);
oldTimestamp.current = timestamp;
console.log("LOOP");
update(secondsPassed);
draw();
animationID = requestAnimationFrame(loop);
};
animationID = requestAnimationFrame(loop);
return cancelAnimationFrame(animationID);
}, []);
const update = (secondsPassed: number) => {};
const draw = () => {
console.log("DRAW");
const ctx = cv && cv.current && cv.current.getContext("2d");
if (ctx) {
ctx.beginPath();
ctx.arc(100, 75, 50, 0, 2 * Math.PI);
ctx.stroke();
}
};
return (
<div>
<canvas ref={cv}></canvas>
</div>
);
};
import*as React from“React”;
从“react”导入{useLayoutEffect,useRef};
导出接口道具{}
导出常量循环:React.FC=()=>{
const cv=useRef(空);
const oldTimestamp=useRef(0);
useLayoutEffect(()=>{
设animationID=0;
console.log(“useffect”);
常量循环=(时间戳:数字)=>{
设secondsPassed=(timestamp-oldtimstamp.current)/1000;
secondsPassed=数学最小值(secondsPassed,0.1);
oldTimestamp.current=时间戳;
console.log(“循环”);
更新(第二次);
draw();
animationID=请求AnimationFrame(循环);
};
animationID=请求AnimationFrame(循环);
返回cancelAnimationFrame(animationID);
}, []);
const update=(secondsPassed:number)=>{};
常量绘图=()=>{
控制台日志(“绘图”);
const ctx=cv&&cv.current&&cv.current.getContext(“2d”);
如果(ctx){
ctx.beginPath();
ctx.arc(100,75,50,0,2*Math.PI);
ctx.stroke();
}
};
返回(
);
};
我已经添加了三个console.log
调用来帮助识别发生了什么。仅ATMconsole.log(“useffect”)正在记录代码>,但没有其他记录。在我看来,animationID=requestAnimationFrame(循环)useLayoutEffect
中的code>未调用循环
回调
我认为useLayoutEffect
中的requestAnimationFrame
设置是正确的
我做错了什么?您应立即取消动画帧,而应返回函数:
return()=>cancelAnimationFrame(animationID)
如果立即取消动画帧,则应返回函数:
return()=>cancelAnimationFrame(animationID)
谢谢!有时候你只需要另一双眼睛:)谢谢!有时候你只需要另一双眼睛:)