使用 JSON 和 Material UI 嵌套菜单

Question

我正在尝试将数据绑定到嵌套菜单级别的 MenuItems。我可以成功映射数据以填充主要级别，但子菜单给我一个错误。

我的 JSON 看起来像这样：

const languages = [
    {
        name: 'English',
        icon: './assets/images/flags/uk.png',
        link: ''
    },
    {
        name: 'Español',
        icon: './assets/images/flags/Spain.png',
        link: ''
    },
    {
        name: 'Français',
        icon: './assets/images/flags/France.png',
        link: ''
    }
];

我将子菜单保存在一个 const 中，这样我就可以在渲染中使用它。（我相信这是我的问题领域，但不确定我需要做什么）

class Menu extends React.Component {
    constructor(props) {
        super(props);
        this.state = {
            show: false,
            open: false
        }
    }
    render() {
        const { colorOption } = this.props;

        //the code inside this const will work if I insert it inside my IconMenu. But it doesn't work inside the menuItems property which should be able to hold MenuItem objects    
        const languageMenu = {languages.map((item, index) => (
            <MenuItem
                key={index}
                className={classnames('menu-item', {
                    'bg-color-medlight': ['11', '12', '13', '14', '15', '16'].indexOf(colorOption) >= 0,
                    'bg-color-meddark': ['21', '22', '23', '24', '25', '26'].indexOf(colorOption) >= 0
                })}
                primaryText={languages[index].name}
                style={{userMenuItem}}
                leftIcon={
                    <img className="flag" src={languages[index].icon}/>
                }/>
        ))}

        return(
        <div style={{zIndex:2}}>
            <ul className="list-unstyled">
                    <li>
                        <IconMenu
                            className="user"
                            iconButtonElement={
                                <RaisedButton style={ImgIconButtonStyle}><PersonalMenuIcon/></RaisedButton>
                            }
                            onChange={this.handleChange}
                            anchorOrigin={{horizontal: 'right', vertical: 'bottom'}}
                            targetOrigin={{horizontal: 'right', vertical: 'top'}}>

                            <MenuItem
                                className={classnames('menu-item', {
                                    'bg-color-medlight': ['11', '12', '13', '14', '15', '16'].indexOf(colorOption) >= 0,
                                    'bg-color-meddark': ['21', '22', '23', '24', '25', '26'].indexOf(colorOption) >= 0
                                })}
                                primaryText="English"
                                rightIcon={<ArrowDropRight />}
                                style={{userMenuItem}}
                                leftIcon={
                                    <img className="flag" src="./assets/images/flags/uk.png"/>
                                }
                                menuItems={{languageMenu}}
                                />
                        </IconMenu>
                    </li>
                </ul>
            </div>
        );
    } 

}

在完美世界中，常规嵌套菜单如下所示：

import React from 'react';
import IconMenu from 'material-ui/IconMenu';
import MenuItem from 'material-ui/MenuItem';
import IconButton from 'material-ui/IconButton';
import Divider from 'material-ui/Divider';
import Download from 'material-ui/svg-icons/file/file-download';
import ArrowDropRight from 'material-ui/svg-icons/navigation-arrow-drop-right';
import MoreVertIcon from 'material-ui/svg-icons/navigation/more-vert';

/**
 * Example of nested menus within an IconMenu.
 */
const IconMenuExampleNested = () => (
  <IconMenu
    iconButtonElement={<IconButton><MoreVertIcon /></IconButton>}
    anchorOrigin={{horizontal: 'left', vertical: 'top'}}
    targetOrigin={{horizontal: 'left', vertical: 'top'}}
  >
    <MenuItem
      primaryText="Copy & Paste"
      rightIcon={<ArrowDropRight />}
      menuItems={[
        <MenuItem primaryText="Cut" />,
        <MenuItem primaryText="Copy" />,
        <Divider />,
        <MenuItem primaryText="Paste" />,
      ]}
    />

    <MenuItem
      primaryText="Case Tools"
      rightIcon={<ArrowDropRight />}
      menuItems={[
        <MenuItem primaryText="UPPERCASE" />,
        <MenuItem primaryText="lowercase" />,
        <MenuItem primaryText="CamelCase" />,
        <MenuItem primaryText="Propercase" />,
      ]}
    />

  </IconMenu>
);

export default IconMenuExampleNested;

我得到的错误是

Module build failed: SyntaxError: C:/xampp/htdocs/ScalaCMReact/src/components/Header/UserMenu.js: Unexpected token, expected , (109:33)

107 |       const { colorOption } = this.props;
108 | 
109 |       const languageMenu = {languages.map((item, index) => (
    |                                      ^
110 |           <MenuItem
111 |               key={index}
112 |               className={classnames('menu-item', {

@ ./src/components/Header/index.js 23:16-37
@ ./src/routes/app/components/MainApp.js
@ ./src/routes/app/index.js
@ ./src/client.js
@ multi (webpack)-dev-server/client?http://localhost:8000 webpack/hot/dev-server webpack-dev-server/client?http://0.0.0.0:8000/ webpack/hot/only-dev-server react-hot-loader/patch ./client.js

我做错了什么？

提前致谢

Answer 1

似乎无效 javascript

const languageMenu = {languages.map((item, index) => (
            <MenuItem
                key={index}
                className={classnames('menu-item', {
                    'bg-color-medlight': ['11', '12', '13', '14', '15', '16'].indexOf(colorOption) >= 0,
                    'bg-color-meddark': ['21', '22', '23', '24', '25', '26'].indexOf(colorOption) >= 0
                })}
                primaryText={languages[index].name}
                style={{userMenuItem}}
                leftIcon={
                    <img className="flag" src={languages[index].icon}/>
                }/>
        ))}

如果您尝试创建一个数组数组，那么外括号应该是 []。如果它是一个包含 MenuItem 数组的属性的对象，那么

const languageMenu = {languages: languages.map((item, index) => (
            <MenuItem
                key={index}
                className={classnames('menu-item', {
                    'bg-color-medlight': ['11', '12', '13', '14', '15', '16'].indexOf(colorOption) >= 0,
                    'bg-color-meddark': ['21', '22', '23', '24', '25', '26'].indexOf(colorOption) >= 0
                })}
                primaryText={languages[index].name}
                style={{userMenuItem}}
                leftIcon={
                    <img className="flag" src={languages[index].icon}/>
                }/>
        ))}

如果你想将 languageMenu 设置为反应元素，那么

const languageMenu = <div>
{languages.map((item, index) => (
            <MenuItem
                key={index}
                className={classnames('menu-item', {
                    'bg-color-medlight': ['11', '12', '13', '14', '15', '16'].indexOf(colorOption) >= 0,
                    'bg-color-meddark': ['21', '22', '23', '24', '25', '26'].indexOf(colorOption) >= 0
                })}
                primaryText={languages[index].name}
                style={{userMenuItem}}
                leftIcon={
                    <img className="flag" src={languages[index].icon}/>
                }/>
        ))}
</div>

使用 JSON 和 Material UI 嵌套菜单

Using JSON with Material UI nested menus

reactjs

material-ui