反应| Items.map不是函数 [英] React | Items.map is not a function
问题描述
我正在使用Downshift,以创建显示某些菜单选项的下拉菜单.我用降档创建了一个可重用的React组件,但是现在出现了这个错误:
I am using Downshift, in order to create a dropdown that displays some menu options. I created a reusable React component with downshift, but now I get this error:
Uncaught TypeError: items.map is not a function
at IconDropdown.react__WEBPACK_IMPORTED_MODULE_2___default.a.createElement.react__WEBPACK_IMPORTED_MODULE_2___default.a.createElement (index.jsx:29)
以下是此错误所指的代码:
Here is the code this error refers to:
{isOpen ? (
<div className="dropdown-menu">
{items.map(item => ( // Specifically this map
<button
type="button"
{...getItemProps({ item })}
key={item}
className="dropdown-item"
>
<Icon icon={item.icon} /> {item.name}
</button>
))}
</div>
) : null}
我正在这样在我的主屏幕组件中使用它:
And I am using it in my main Screen Component like this:
items = {
editUser: {
name: 'Edit Info',
icon: 'pencil-square-o'
},
changePassword: {
name: 'Change Password',
icon: 'lock'
},
deleteUsed: {
name: 'Delete user',
icon: 'trash-o'
}
};
render() {
return (
<IconDropdown items={this.items} />
)}
预期的行为: 呈现菜单项及其相应图标的列表.
Expected behavior: Render a list of menu items, with their corresponding icons.
当前行为: 我收到上述错误.我不确定这段代码有什么问题.在我看来,这是正确的.
Current Behavior: I get the above error. I am not sure what is wrong with this code. On my eyes this is correct.
如果您愿意,我可以发布整个组件.
I can post the entire component if you want, just let me know.
更新,整个下拉列表组件:
import React, { Fragment } from 'react';
import PropTypes from 'prop-types';
import Downshift from 'downshift';
import Icon from 'lenses/common/components/Icon';
import './styles.scss';
const IconDropdown = ({ items, ...otherProps }) => (
<Fragment>
<Downshift {...otherProps}>
{({ getItemProps, isOpen, toggleMenu }) => (
<div>
<div className="btn-group">
<button
id="my-select"
type="button"
className="btn btn-primary dropdown-toggle dropdown-toggle-split"
onClick={toggleMenu}
data-toggle="dropdown"
aria-haspopup="true"
aria-expanded={isOpen}
>
<span className="sr-only">Toggle Dropdown</span>
</button>
{isOpen ? (
<div className="dropdown-menu">
{items.map(item => (
<button
type="button"
{...getItemProps({ item })}
key={item}
className="dropdown-item"
>
<Icon icon={item.icon} /> {item.name}
</button>
))}
</div>
) : null}
</div>
</div>
)}
</Downshift>
</Fragment>
);
IconDropdown.propTypes = {
items: PropTypes.shape({
name: PropTypes.string.isRequired,
icon: PropTypes.string
})
};
export default IconDropdown;
推荐答案
.map
在对象{}
中不存在,仅在数组[]
中存在.您可以:
.map
doesn't exist from an object {}
, it only exists from an array []
. You can:
- 将对象更改为数组
- 使用
Object.keys(items).map(...)
- 使用
lodash.map
- Change your object to an array
- Use
Object.keys(items).map(...)
- Use
lodash.map
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