如何使用 react-select 呈现 "N items selected" 而不是 N selected 项目的列表
How to render "N items selected" rather than the list of N selected items with react-select
我正在研究使用 react-select 作为城市选择器的选择器，用户可以在其中选择 1 个或多个城市来过滤一些数据。这是在我的页面中呈现的屏幕截图：
城市列表可能很大，如果一次选择大量城市，我不希望选择器超出其蓝色容器。这是我现在模拟时发生的情况：
我不太喜欢它！我能想到的一种替代方法是呈现“选择的 4 个城市”而不是整个列表。这将在页面上具有可预测的大小。
react-select如何做到这一点？
在我看来，我会覆盖 css 以固定大小。是css的事情。我将检查元素并进行更改。
让我们看看上面的例子。这是您需要调整的css：
.Select-control {
background-color: #fff;
border-color: #d9d9d9 #ccc #b3b3b3;
border-radius: 4px;
border: 1px solid #ccc;
color: #333;
cursor: default;
display: table;
border-spacing: 0;
border-collapse: separate;
height: 36px;
outline: none;
overflow: hidden;
position: relative;
width: 100%;
}
现在删除 display: table; 并添加适当的高度。
注意：此答案适用于 react-select v1。有关 v3 的解决方案，请参阅 。
正在渲染“N 项 selected”
这可以通过 valueRenderer 和 className 道具以及最少量的 CSS 来实现。
这里我正常显示前三个 select 离子，然后在 selected 超过 4 个项目时显示“N 项 selected”。显示 remove selection 图标 (×) 除了“N items selected”是没有意义的，所以我也删除了那个（CSS).
class App extends React.Component {
state = {
value: [],
}
className = () => {
const baseClassName = 'my-react-select';
if (this.state.value.length <= 3) {
return baseClassName;
}
return `${baseClassName} ${baseClassName}--compact`;
}
handleChange = (value) => {
this.setState({ value });
}
renderValue = (option) => {
// The first three selections are rendered normally
if (this.state.value.length <= 3) {
return option.label;
}
// With more selections, render "N items selected".
// Other than the first one are hidden in CSS.
return <span>{this.state.value.length} items selected</span>;
}
render() {
return (
<Select
className={this.className()}
multi
onChange={this.handleChange}
options={[
{ value: 'zero', label: 'Zero' },
{ value: 'one', label: 'One' },
{ value: 'two', label: 'Two' },
{ value: 'three', label: 'Three' },
{ value: 'four', label: 'Four' },
{ value: 'five', label: 'Five' },
{ value: 'six', label: 'Six' },
{ value: 'seven', label: 'Seven' },
{ value: 'eight', label: 'Eight' },
{ value: 'nine', label: 'Nine' },
]}
value={this.state.value}
valueRenderer={this.renderValue}
/>
);
}
}
ReactDOM.render(<App />, document.getElementById('root'));
.my-react-select {
/* Custom styles */
}
.my-react-select--compact .Select-value:first-child {
font-style: italic;
}
.my-react-select--compact .Select-value:first-child .Select-value-icon,
.my-react-select--compact .Select-value:nth-child(n+2) {
display: none;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://unpkg.com/prop-types@15.5.10/prop-types.js"></script>
<script src="https://unpkg.com/classnames@2.2.5/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@2.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select@1.3.0/dist/react-select.js"></script>
<link rel="stylesheet" href="https://unpkg.com/react-select@1.3.0/dist/react-select.css">
<div id="root"></div>
替代方法
查看您的屏幕截图，看起来 space 最多显示四个 select 离子，而不会造成 selector 溢出。当超过 4 个城市 selected 时显示“N 项 selected”， 您可以正常显示前 3 个 selections 然后“+N 更多." 像这样：
- 城市A
- A市，B市
- A市、B市、C市
- A市、B市、C市，+1个
- A市、B市、C市，还有2个
- A市、B市、C市，还有3个
- 等等
从用户体验的角度来看，我认为正常显示前 3 个左右 selection 很好。如果在第 4 个城市 selected.
之后，每个 selection 突然隐藏在文本“4 items selected”后面，这会让人感到困惑。
这个解决方案与第一个非常相似。 className 道具现在只是一个字符串。 renderValue 方法和 CSS select 或者有点不同。
class App extends React.Component {
state = {
value: [],
}
handleChange = (value) => {
this.setState({ value });
}
renderValue = (option) => {
// The first three values are rendered normally
if (this.state.value.indexOf(option) < 3) {
return option.label;
}
// Render the rest as "+ N more".
// Other than the first one are hidden in CSS.
return <span>+ {this.state.value.length - 3} more</span>;
}
render() {
return (
<Select
className='my-react-select'
multi
onChange={this.handleChange}
options={[
{ value: 'zero', label: 'Zero' },
{ value: 'one', label: 'One' },
{ value: 'two', label: 'Two' },
{ value: 'three', label: 'Three' },
{ value: 'four', label: 'Four' },
{ value: 'five', label: 'Five' },
{ value: 'six', label: 'Six' },
{ value: 'seven', label: 'Seven' },
{ value: 'eight', label: 'Eight' },
{ value: 'nine', label: 'Nine' },
]}
value={this.state.value}
valueRenderer={this.renderValue}
/>
);
}
}
ReactDOM.render(<App />, document.getElementById('root'));
/* If you change the amount of how many selections are shown normally,
* be sure to adjust these selectors accordingly. */
.my-react-select .Select-value:nth-child(4) {
font-style: italic;
}
.my-react-select .Select-value:nth-child(4) .Select-value-icon,
.my-react-select .Select-value:nth-child(n+5) {
display: none;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://unpkg.com/prop-types@15.5.10/prop-types.js"></script>
<script src="https://unpkg.com/classnames@2.2.5/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@2.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select@1.3.0/dist/react-select.js"></script>
<link rel="stylesheet" href="https://unpkg.com/react-select@1.3.0/dist/react-select.css">
<div id="root"></div>
这是显示 select 离子的另一种方法：
- 城市A
- A市，B市
- A市、B市、C市
- A市、B市、C市、D市
- A市、B市、C市，还有2个
- A市、B市、C市，还有3个
- 等等
从用户体验的角度来看，显示“+ 1 more”而不是显示值有点傻，所以在我看来这是最好的选择。
renderValue 方法再次有点不同。 CSS select or 现在有点丑陋和复杂，但它们有效。
class App extends React.Component {
state = {
value: [],
}
handleChange = (value) => {
this.setState({ value });
}
renderValue = (option) => {
// The first four values are rendered normally
if (this.state.value.length <= 4) {
return option.label;
}
// The first 3 values are rendered normally when
// more than 4 selections have been made
if (this.state.value.indexOf(option) < 3) {
return option.label;
}
// Render the rest as "+ N more".
// Other than the first one are hidden in CSS.
return <span>+ {this.state.value.length - 3} more</span>;
}
render() {
return (
<Select
className='my-react-select'
multi
onChange={this.handleChange}
options={[
{ value: 'zero', label: 'Zero' },
{ value: 'one', label: 'One' },
{ value: 'two', label: 'Two' },
{ value: 'three', label: 'Three' },
{ value: 'four', label: 'Four' },
{ value: 'five', label: 'Five' },
{ value: 'six', label: 'Six' },
{ value: 'seven', label: 'Seven' },
{ value: 'eight', label: 'Eight' },
{ value: 'nine', label: 'Nine' },
]}
value={this.state.value}
valueRenderer={this.renderValue}
/>
);
}
}
ReactDOM.render(<App />, document.getElementById('root'));
/* If you change the amount of how many selections are shown normally,
* be sure to adjust these selectors accordingly. */
.my-react-select .Select-value:nth-child(4):not(:nth-last-child(2)) {
font-style: italic;
}
.my-react-select .Select-value:nth-child(4):not(:nth-last-child(2)) .Select-value-icon,
.my-react-select .Select-value:nth-child(n+5) {
display: none;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://unpkg.com/prop-types@15.5.10/prop-types.js"></script>
<script src="https://unpkg.com/classnames@2.2.5/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@2.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select@1.3.0/dist/react-select.js"></script>
<link rel="stylesheet" href="https://unpkg.com/react-select@1.3.0/dist/react-select.css">
<div id="root"></div>
这是我使用 react-select 3.x 更新的答案。不涉及 css。我用我的自定义 multi-values 消息覆盖 ValueContainer 的子级。在此之前，您需要导入以下内容：
import React from "react";
import Select, { components } from "react-select";
变体 1
显示一般消息：n items selected
const ValueContainer = ({ children, ...props }) => {
let [values, input] = children;
if (Array.isArray(values)) {
const plural = values.length === 1 ? "" : "s";
values = `${values.length} item${plural} selected`;
}
return (
<components.ValueContainer {...props}>
{values}
{input}
</components.ValueContainer>
);
};
结果
变体 2
在显示通用消息之前显示一些命名项目：item1, item2, item3 and n others selected
const ValueContainer = ({ children, ...props }) => {
let [values, input] = children;
if (Array.isArray(values)) {
const val = (i: number) => values[i].props.children;
const { length } = values;
switch (length) {
case 1:
values = `${val(0)} selected`;
break;
case 2:
values = `${val(0)} and ${val(1)} selected`;
break;
case 3:
values = `${val(0)}, ${val(1)} and ${val(2)} selected`;
break;
default:
const plural = values.length === 3 + 1 ? "" : "s";
const otherCount = length - 3;
values = `${val(0)}, ${val(1)}, ${val(
2
)} and ${otherCount} other${plural} selected`;
break;
}
}
return (
<components.ValueContainer {...props}>
{values}
{input}
</components.ValueContainer>
);
};
用法
<Select
{...}
isMulti
hideSelectedOptions={false}
components={{ ValueContainer }}
/>
现场演示
我正在研究使用 react-select 作为城市选择器的选择器，用户可以在其中选择 1 个或多个城市来过滤一些数据。这是在我的页面中呈现的屏幕截图：
城市列表可能很大，如果一次选择大量城市，我不希望选择器超出其蓝色容器。这是我现在模拟时发生的情况：
我不太喜欢它！我能想到的一种替代方法是呈现“选择的 4 个城市”而不是整个列表。这将在页面上具有可预测的大小。
react-select如何做到这一点？
在我看来，我会覆盖 css 以固定大小。是css的事情。我将检查元素并进行更改。
让我们看看上面的例子。这是您需要调整的css：
.Select-control {
background-color: #fff;
border-color: #d9d9d9 #ccc #b3b3b3;
border-radius: 4px;
border: 1px solid #ccc;
color: #333;
cursor: default;
display: table;
border-spacing: 0;
border-collapse: separate;
height: 36px;
outline: none;
overflow: hidden;
position: relative;
width: 100%;
}
现在删除 display: table; 并添加适当的高度。
注意：此答案适用于 react-select v1。有关 v3 的解决方案，请参阅
正在渲染“N 项 selected”
这可以通过 valueRenderer 和 className 道具以及最少量的 CSS 来实现。
这里我正常显示前三个 select 离子，然后在 selected 超过 4 个项目时显示“N 项 selected”。显示 remove selection 图标 (×) 除了“N items selected”是没有意义的，所以我也删除了那个（CSS).
class App extends React.Component {
state = {
value: [],
}
className = () => {
const baseClassName = 'my-react-select';
if (this.state.value.length <= 3) {
return baseClassName;
}
return `${baseClassName} ${baseClassName}--compact`;
}
handleChange = (value) => {
this.setState({ value });
}
renderValue = (option) => {
// The first three selections are rendered normally
if (this.state.value.length <= 3) {
return option.label;
}
// With more selections, render "N items selected".
// Other than the first one are hidden in CSS.
return <span>{this.state.value.length} items selected</span>;
}
render() {
return (
<Select
className={this.className()}
multi
onChange={this.handleChange}
options={[
{ value: 'zero', label: 'Zero' },
{ value: 'one', label: 'One' },
{ value: 'two', label: 'Two' },
{ value: 'three', label: 'Three' },
{ value: 'four', label: 'Four' },
{ value: 'five', label: 'Five' },
{ value: 'six', label: 'Six' },
{ value: 'seven', label: 'Seven' },
{ value: 'eight', label: 'Eight' },
{ value: 'nine', label: 'Nine' },
]}
value={this.state.value}
valueRenderer={this.renderValue}
/>
);
}
}
ReactDOM.render(<App />, document.getElementById('root'));
.my-react-select {
/* Custom styles */
}
.my-react-select--compact .Select-value:first-child {
font-style: italic;
}
.my-react-select--compact .Select-value:first-child .Select-value-icon,
.my-react-select--compact .Select-value:nth-child(n+2) {
display: none;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://unpkg.com/prop-types@15.5.10/prop-types.js"></script>
<script src="https://unpkg.com/classnames@2.2.5/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@2.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select@1.3.0/dist/react-select.js"></script>
<link rel="stylesheet" href="https://unpkg.com/react-select@1.3.0/dist/react-select.css">
<div id="root"></div>
替代方法
查看您的屏幕截图，看起来 space 最多显示四个 select 离子，而不会造成 selector 溢出。当超过 4 个城市 selected 时显示“N 项 selected”， 您可以正常显示前 3 个 selections 然后“+N 更多." 像这样：
- 城市A
- A市，B市
- A市、B市、C市
- A市、B市、C市，+1个
- A市、B市、C市，还有2个
- A市、B市、C市，还有3个
- 等等
从用户体验的角度来看，我认为正常显示前 3 个左右 selection 很好。如果在第 4 个城市 selected.
之后，每个 selection 突然隐藏在文本“4 items selected”后面，这会让人感到困惑。这个解决方案与第一个非常相似。 className 道具现在只是一个字符串。 renderValue 方法和 CSS select 或者有点不同。
class App extends React.Component {
state = {
value: [],
}
handleChange = (value) => {
this.setState({ value });
}
renderValue = (option) => {
// The first three values are rendered normally
if (this.state.value.indexOf(option) < 3) {
return option.label;
}
// Render the rest as "+ N more".
// Other than the first one are hidden in CSS.
return <span>+ {this.state.value.length - 3} more</span>;
}
render() {
return (
<Select
className='my-react-select'
multi
onChange={this.handleChange}
options={[
{ value: 'zero', label: 'Zero' },
{ value: 'one', label: 'One' },
{ value: 'two', label: 'Two' },
{ value: 'three', label: 'Three' },
{ value: 'four', label: 'Four' },
{ value: 'five', label: 'Five' },
{ value: 'six', label: 'Six' },
{ value: 'seven', label: 'Seven' },
{ value: 'eight', label: 'Eight' },
{ value: 'nine', label: 'Nine' },
]}
value={this.state.value}
valueRenderer={this.renderValue}
/>
);
}
}
ReactDOM.render(<App />, document.getElementById('root'));
/* If you change the amount of how many selections are shown normally,
* be sure to adjust these selectors accordingly. */
.my-react-select .Select-value:nth-child(4) {
font-style: italic;
}
.my-react-select .Select-value:nth-child(4) .Select-value-icon,
.my-react-select .Select-value:nth-child(n+5) {
display: none;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://unpkg.com/prop-types@15.5.10/prop-types.js"></script>
<script src="https://unpkg.com/classnames@2.2.5/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@2.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select@1.3.0/dist/react-select.js"></script>
<link rel="stylesheet" href="https://unpkg.com/react-select@1.3.0/dist/react-select.css">
<div id="root"></div>
这是显示 select 离子的另一种方法：
- 城市A
- A市，B市
- A市、B市、C市
- A市、B市、C市、D市
- A市、B市、C市，还有2个
- A市、B市、C市，还有3个
- 等等
从用户体验的角度来看，显示“+ 1 more”而不是显示值有点傻，所以在我看来这是最好的选择。
renderValue 方法再次有点不同。 CSS select or 现在有点丑陋和复杂，但它们有效。
class App extends React.Component {
state = {
value: [],
}
handleChange = (value) => {
this.setState({ value });
}
renderValue = (option) => {
// The first four values are rendered normally
if (this.state.value.length <= 4) {
return option.label;
}
// The first 3 values are rendered normally when
// more than 4 selections have been made
if (this.state.value.indexOf(option) < 3) {
return option.label;
}
// Render the rest as "+ N more".
// Other than the first one are hidden in CSS.
return <span>+ {this.state.value.length - 3} more</span>;
}
render() {
return (
<Select
className='my-react-select'
multi
onChange={this.handleChange}
options={[
{ value: 'zero', label: 'Zero' },
{ value: 'one', label: 'One' },
{ value: 'two', label: 'Two' },
{ value: 'three', label: 'Three' },
{ value: 'four', label: 'Four' },
{ value: 'five', label: 'Five' },
{ value: 'six', label: 'Six' },
{ value: 'seven', label: 'Seven' },
{ value: 'eight', label: 'Eight' },
{ value: 'nine', label: 'Nine' },
]}
value={this.state.value}
valueRenderer={this.renderValue}
/>
);
}
}
ReactDOM.render(<App />, document.getElementById('root'));
/* If you change the amount of how many selections are shown normally,
* be sure to adjust these selectors accordingly. */
.my-react-select .Select-value:nth-child(4):not(:nth-last-child(2)) {
font-style: italic;
}
.my-react-select .Select-value:nth-child(4):not(:nth-last-child(2)) .Select-value-icon,
.my-react-select .Select-value:nth-child(n+5) {
display: none;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://unpkg.com/prop-types@15.5.10/prop-types.js"></script>
<script src="https://unpkg.com/classnames@2.2.5/index.js"></script>
<script src="https://unpkg.com/react-input-autosize@2.0.0/dist/react-input-autosize.js"></script>
<script src="https://unpkg.com/react-select@1.3.0/dist/react-select.js"></script>
<link rel="stylesheet" href="https://unpkg.com/react-select@1.3.0/dist/react-select.css">
<div id="root"></div>
这是我使用 react-select 3.x 更新的答案。不涉及 css。我用我的自定义 multi-values 消息覆盖 ValueContainer 的子级。在此之前，您需要导入以下内容：
import React from "react";
import Select, { components } from "react-select";
变体 1
显示一般消息：n items selected
const ValueContainer = ({ children, ...props }) => {
let [values, input] = children;
if (Array.isArray(values)) {
const plural = values.length === 1 ? "" : "s";
values = `${values.length} item${plural} selected`;
}
return (
<components.ValueContainer {...props}>
{values}
{input}
</components.ValueContainer>
);
};
结果
变体 2
在显示通用消息之前显示一些命名项目：item1, item2, item3 and n others selected
const ValueContainer = ({ children, ...props }) => {
let [values, input] = children;
if (Array.isArray(values)) {
const val = (i: number) => values[i].props.children;
const { length } = values;
switch (length) {
case 1:
values = `${val(0)} selected`;
break;
case 2:
values = `${val(0)} and ${val(1)} selected`;
break;
case 3:
values = `${val(0)}, ${val(1)} and ${val(2)} selected`;
break;
default:
const plural = values.length === 3 + 1 ? "" : "s";
const otherCount = length - 3;
values = `${val(0)}, ${val(1)}, ${val(
2
)} and ${otherCount} other${plural} selected`;
break;
}
}
return (
<components.ValueContainer {...props}>
{values}
{input}
</components.ValueContainer>
);
};
用法
<Select
{...}
isMulti
hideSelectedOptions={false}
components={{ ValueContainer }}
/>