反应抽屉状态管理

React Drawer State Management

我整理了一个页面,左边是侧边栏,顶部是应用栏,还有内容区。作为一个单一的 Gigantic 组件,它一切正常。我认为我们都喜欢 React 的想法和灵活性是让页面上的各种元素成为不同的组件。因此,我继续将 Sidebar、Appbar、Content 区域作为它们自己的组件。显然,现在有一个状态问题,因为我想不出一种方法来将侧边栏的状态从隐藏更改为显示,以便在页面上进行适当的更改。

现在提出一个问题,为什么使用 React 进行状态管理似乎仍然是可选的,而且许多人只推荐用于大型项目?如果没有状态管理,我不能用 Sidebar 做一个简单的项目吗?可能有一些方法可以解决这个特定问题,例如点击 App.js 之类的主要组件,并在每次用户单击按钮时将其发送到每个组件。我的意思是,不可能只是,这不是一个好的解决方案。

最后,对于想要查看代码的严格编码人员,我使用了 Material UI,这里是 Persistent Drawer:https://material-ui.com/demos/drawers/

import React from 'react';
import PropTypes from 'prop-types';
import classNames from 'classnames';
import { withStyles } from '@material-ui/core/styles';
import Drawer from '@material-ui/core/Drawer';
import CssBaseline from '@material-ui/core/CssBaseline';
import AppBar from '@material-ui/core/AppBar';
import Toolbar from '@material-ui/core/Toolbar';
import List from '@material-ui/core/List';
import Typography from '@material-ui/core/Typography';
import Divider from '@material-ui/core/Divider';
import IconButton from '@material-ui/core/IconButton';
import MenuIcon from '@material-ui/icons/Menu';
import ChevronLeftIcon from '@material-ui/icons/ChevronLeft';
import ChevronRightIcon from '@material-ui/icons/ChevronRight';
import ListItem from '@material-ui/core/ListItem';
import ListItemIcon from '@material-ui/core/ListItemIcon';
import ListItemText from '@material-ui/core/ListItemText';
import InboxIcon from '@material-ui/icons/MoveToInbox';
import MailIcon from '@material-ui/icons/Mail';

const drawerWidth = 240;

const styles = theme => ({
  root: {
    display: 'flex',
  },
  appBar: {
    transition: theme.transitions.create(['margin', 'width'], {
      easing: theme.transitions.easing.sharp,
      duration: theme.transitions.duration.leavingScreen,
    }),
  },
  appBarShift: {
    width: `calc(100% - ${drawerWidth}px)`,
    marginLeft: drawerWidth,
    transition: theme.transitions.create(['margin', 'width'], {
      easing: theme.transitions.easing.easeOut,
      duration: theme.transitions.duration.enteringScreen,
    }),
  },
  menuButton: {
    marginLeft: 12,
    marginRight: 20,
  },
  hide: {
    display: 'none',
  },
  drawer: {
    width: drawerWidth,
    flexShrink: 0,
  },
  drawerPaper: {
    width: drawerWidth,
  },
  drawerHeader: {
    display: 'flex',
    alignItems: 'center',
    padding: '0 8px',
    ...theme.mixins.toolbar,
    justifyContent: 'flex-end',
  },
  content: {
    flexGrow: 1,
    padding: theme.spacing.unit * 3,
    transition: theme.transitions.create('margin', {
      easing: theme.transitions.easing.sharp,
      duration: theme.transitions.duration.leavingScreen,
    }),
    marginLeft: -drawerWidth,
  },
  contentShift: {
    transition: theme.transitions.create('margin', {
      easing: theme.transitions.easing.easeOut,
      duration: theme.transitions.duration.enteringScreen,
    }),
    marginLeft: 0,
  },
});

class PersistentDrawerLeft extends React.Component {
  state = {
    open: false,
  };

  handleDrawerOpen = () => {
    this.setState({ open: true });
  };

  handleDrawerClose = () => {
    this.setState({ open: false });
  };

  render() {
    const { classes, theme } = this.props;
    const { open } = this.state;

    return (
      <div className={classes.root}>
        <CssBaseline />
        <AppBar
          position="fixed"
          className={classNames(classes.appBar, {
            [classes.appBarShift]: open,
          })}
        >
          <Toolbar disableGutters={!open}>
            <IconButton
              color="inherit"
              aria-label="Open drawer"
              onClick={this.handleDrawerOpen}
              className={classNames(classes.menuButton, open && classes.hide)}
            >
              <MenuIcon />
            </IconButton>
            <Typography variant="h6" color="inherit" noWrap>
              Persistent drawer
            </Typography>
          </Toolbar>
        </AppBar>
        <Drawer
          className={classes.drawer}
          variant="persistent"
          anchor="left"
          open={open}
          classes={{
            paper: classes.drawerPaper,
          }}
        >
          <div className={classes.drawerHeader}>
            <IconButton onClick={this.handleDrawerClose}>
              {theme.direction === 'ltr' ? <ChevronLeftIcon /> : <ChevronRightIcon />}
            </IconButton>
          </div>
          <Divider />
          <List>
            {['Inbox', 'Starred', 'Send email', 'Drafts'].map((text, index) => (
              <ListItem button key={text}>
                <ListItemIcon>{index % 2 === 0 ? <InboxIcon /> : <MailIcon />}</ListItemIcon>
                <ListItemText primary={text} />
              </ListItem>
            ))}
          </List>
          <Divider />
          <List>
            {['All mail', 'Trash', 'Spam'].map((text, index) => (
              <ListItem button key={text}>
                <ListItemIcon>{index % 2 === 0 ? <InboxIcon /> : <MailIcon />}</ListItemIcon>
                <ListItemText primary={text} />
              </ListItem>
            ))}
          </List>
        </Drawer>
        <main
          className={classNames(classes.content, {
            [classes.contentShift]: open,
          })}
        >
          <div className={classes.drawerHeader} />
          <Typography paragraph>
            Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor
            incididunt ut labore et dolore magna aliqua. Rhoncus dolor purus non enim praesent
            elementum facilisis leo vel. Risus at ultrices mi tempus imperdiet. Semper risus in
            hendrerit gravida rutrum quisque non tellus. Convallis convallis tellus id interdum
            velit laoreet id donec ultrices. Odio morbi quis commodo odio aenean sed adipiscing.
            Amet nisl suscipit adipiscing bibendum est ultricies integer quis. Cursus euismod quis
            viverra nibh cras. Metus vulputate eu scelerisque felis imperdiet proin fermentum leo.
            Mauris commodo quis imperdiet massa tincidunt. Cras tincidunt lobortis feugiat vivamus
            at augue. At augue eget arcu dictum varius duis at consectetur lorem. Velit sed
            ullamcorper morbi tincidunt. Lorem donec massa sapien faucibus et molestie ac.
          </Typography>
          <Typography paragraph>
            Consequat mauris nunc congue nisi vitae suscipit. Fringilla est ullamcorper eget nulla
            facilisi etiam dignissim diam. Pulvinar elementum integer enim neque volutpat ac
            tincidunt. Ornare suspendisse sed nisi lacus sed viverra tellus. Purus sit amet volutpat
            consequat mauris. Elementum eu facilisis sed odio morbi. Euismod lacinia at quis risus
            sed vulputate odio. Morbi tincidunt ornare massa eget egestas purus viverra accumsan in.
            In hendrerit gravida rutrum quisque non tellus orci ac. Pellentesque nec nam aliquam sem
            et tortor. Habitant morbi tristique senectus et. Adipiscing elit duis tristique
            sollicitudin nibh sit. Ornare aenean euismod elementum nisi quis eleifend. Commodo
            viverra maecenas accumsan lacus vel facilisis. Nulla posuere sollicitudin aliquam
            ultrices sagittis orci a.
          </Typography>
        </main>
      </div>
    );
  }
}

PersistentDrawerLeft.propTypes = {
  classes: PropTypes.object.isRequired,
  theme: PropTypes.object.isRequired,
};

export default withStyles(styles, { withTheme: true })(PersistentDrawerLeft);

状态将继续像拆分组件之前一样进行管理 -- 在所有需要它的后代组件共有的最高级别。该状态以及任何管理状态的回调将作为道具传递给需要它的子组件。

顶级组件如下所示:

import React from "react";
import PropTypes from "prop-types";
import { withStyles } from "@material-ui/core/styles";
import CssBaseline from "@material-ui/core/CssBaseline";
import MyAppBar from "./MyAppBar";
import MyContent from "./MyContent";
import MyDrawer from "./MyDrawer";

const styles = theme => ({
  root: {
    display: "flex"
  },
  drawerHeader: {
    display: "flex",
    alignItems: "center",
    padding: "0 8px",
    ...theme.mixins.toolbar,
    justifyContent: "flex-end"
  }
});

class PersistentDrawerLeft extends React.Component {
  state = {
    open: false
  };

  handleDrawerOpen = () => {
    this.setState({ open: true });
  };

  handleDrawerClose = () => {
    this.setState({ open: false });
  };

  render() {
    const { classes } = this.props;
    const { open } = this.state;

    return (
      <div className={classes.root}>
        <CssBaseline />
        <MyAppBar handleDrawerOpen={this.handleDrawerOpen} open={open} />
        <MyDrawer
          handleDrawerClose={this.handleDrawerClose}
          drawerHeaderClass={classes.drawerHeader}
          open={open}
        />
        <MyContent drawerHeaderClass={classes.drawerHeader} open={open} />
      </div>
    );
  }
}

PersistentDrawerLeft.propTypes = {
  classes: PropTypes.object.isRequired,
  theme: PropTypes.object.isRequired
};

export default withStyles(styles)(PersistentDrawerLeft);

然后其他组件就相当简单了。您可以看到沙盒中的所有碎片。