React useNavigationUnsavedChange

2022-09-01  本文已影响0人  wuzinong

在线Demo

import { useCallback, useState, useContext, useEffect } from "react";

import { useNavigate, UNSAFE_NavigationContext } from "react-router-dom";

export const useTest = (

  when: boolean,

  onSuccess: () => void

): {

  navigationWasBlocked: boolean;

  handleCancel: () => void;

  handleOk: () => void;

} => {

  const [nextLocation, setNextLocation] = useState(null);

  const { navigator } = useContext(UNSAFE_NavigationContext);

  const navigate = useNavigate();

  console.log("setNextLocation outer ", nextLocation);

  const handleCancel = () => {

    //点击取消按钮调用此方法,清空当前要跳转到的链接

    setNextLocation(undefined);

  };

  const handleOk = () => {

    //点击了同意按钮

    debugger;

    onSuccess(); //先调用回调函数,此函数在调用此hook时传入

    setNextLocation(undefined); //跳转完毕后清空,因为setState的异步性,放这里和放最后一样

    navigate(nextLocation); //跳转到当前需要跳转的链接,虽然上面设置了undefind但是由于异步性这里获取的还是未清空时的链接

  };

  const blocker: any = useCallback(

    ({ action, location: nextLocation, retry }) => {

      console.log("location ", location);

      debugger;

      switch (action) {

        case "REPLACE": {

          retry();

          return;

        }

        case "POP":

        case "PUSH": {

          //POP:点击浏览器后退按钮

          //PUSH: 点击了某个按钮跳转页面

          setNextLocation(nextLocation); //无论是哪种,都把当前要跳转到的链接信息放入currentLocation

          return;

        }

        default:

          break;

      }

    },

    []

  );

  //调用此hook

  // const { navigationWasBlocked, handleCancel, handleOk } = useTest(true, () => {

  //    console.log('called');

  // });

  useEffect(() => {

    if (!when) return; //当when为false时表示不需要启用此功能

    if (nextLocation) return; //如果NextLocation存在值就跳出

    if (!("block" in navigator)) return; //block属性不存在就跳出,浏览器兼容?

    const unblock = (navigator as any).block((tx: any) => {

      debugger;

      console.log("tttttttttt    ", tx.retry.toString());

      //监听路由变化,每当点击跳转按钮会调用此函数

      //这个函数会传入tx,形如:

      // {

      //     "action": "PUSH",

      //     "location": {

      //         "pathname": "/dummy-test-01",

      //         "hash": "",

      //         "search": "",

      //         "state": null,

      //         "key": "igdvd1g0"

      //     }

      //     "retry":function(){go(delta * -1);}

      // }

    //   debugger;

    //   if (tx.action === "POP") {

    //     tx.action = "REPLACE";

    //   }

      const autoUnblockingTx = {

        ...tx,

        retry() {

          //扩展retry方法

          //如果Replace的情况就会走到这里

          //第一步把绑定的监听事件移除

          unblock();

          //接着调tx上的retry方法

          //go(delta * -1) 比如点击后退delta为1,变成go(-1),改变url

          tx.retry();

        },

      };

      blocker(autoUnblockingTx); //调用blocker函数(设置当前router信息)

    });

    console.log("unblock ", unblock);

    return unblock; //返回block函数的调用结果(是一个function组件卸载时调用此function)移除beforeunload listener

  }, [navigator, blocker, when, nextLocation]);

  return {

    navigationWasBlocked: Boolean(nextLocation),

    handleCancel,

    handleOk,

  };

};

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