Question

我用react路由器实现了material-ui选项卡。当我单击选项卡时，选项卡指示器（该选项卡下方的蓝线）按预期工作，它将移动到按下该选项卡的位置。问题在于，当我重新加载页面时，选项卡指示器会返回到第一个选项卡项目。

我认为这可能是因为选项卡的初始值为零，所以当重新加载页面时，该值再次变为零。

import React, { useState } from 'react';
import Tabs from '@material-ui/core/Tabs';
import Tab from '@material-ui/core/Tab';
import SignIn from '../signIn/SignIn'
import SignUp from '../signUp/SignUp';
import About from '../about/About';
import NavbarStyles from './NavbarStyles';
import { Link, Switch, Route } from 'react-router-dom';
import { Paper } from '@material-ui/core';

/**
 * This component handles the routing and navigating the user to different sections
 */
export default function Navbar() {
  const classes = NavbarStyles();
  const [value, setValue] = useState(0);

  const handleChange = (event, newValue) => {
    setValue(newValue);
  };

  return (
    <div className={classes.root}>
      <Paper>
        <Tabs
          value={value}
          onChange={handleChange}
          variant="scrollable"
          scrollButtons="on"
          indicatorColor="primary"
          textColor="primary"
          aria-label="scrollable force tabs example"
        >
         <Tab label="Sign In" to="/signin" component={Link} />
         <Tab label="Sign Up" to="/signup" component={Link} />
         <Tab label="About" to="/about" component={Link} />
        </Tabs>
      </Paper>

      <Switch>
        <Route component={SignIn} path="/signin" />
        <Route component={SignUp} path="/signup" />
        <Route component={About} path="/about" />
      </Switch>

    </div>
  );
}


import { makeStyles } from '@material-ui/core/styles';

// This component contains the styles that is being used by its intented component
export default function NavbarStyles() {

    const useStyles = makeStyles((theme) => ({
        root: {
          flexGrow: 1,
          width: '100%',
          backgroundColor: theme.palette.background.paper,
        },
      }));

      return useStyles();

}

Answer 1

有同样的问题，这是我如何解决的。由于在刷新页面时Tabs的初始值为0，因此将其重置为home。为防止这种情况，请在handleChange函数的正下方添加一个带有依赖项数组的useEffect。

useEffect(() => {
    let path = props.location.pathname;
    if (path === "/signin" && value !== 0) setValue(0);
    else if (path === "/signup" && value !== 1) setValue(1);
    else if (path === "/about" && value !== 2) setValue(2);
  }, [value,]);

这会在重新加载页面时设置适当的标签值

Answer 2

这基于Firealem Erkos代码。在刷新时，我得到0加载，然后高亮条将滑到我当前的那个。.看起来很奇怪..因此，代替usestate（0），我用currentTab代替了0 ...我计算了下面的代码。现在，刷新0时不会短暂突出显示。

   const currentTab = () => {
    let path = window.location.pathname
    if (path === "/Search") return 1
    else if (path === "/ZoneInformation") return 2
    else if (path === "/Contact") return 3
  }
 
  const [value, setValue] = React.useState(**currentTab**);

重新加载页面时，Material-UI选项卡指示器返回到第一个选项卡项目

2 个答案: