函数式组件缩略图

故事背景

在日常前端开发的过程中，我不止一次的遇到过主视图-缩略图功能的实现。现封装一个组件，将其渲染到不同的位置上去，实现主视图和缩略图的功能，同时提供了接口，保留了一定的定制化功能。

设计思路

1. 使用React.createElement创建带参数的React.FunctionComponentElement<any>对象;
1. 使用React.createPortal产生两个包裹目标组件的待渲染组件M；
1. 使用函数式组件MA将两个M包裹在一起，方便管理，MA的兼具处理数据流的作用；
1. 在合适的地方使用MA，将组件渲染到不同的容器中去，并保留一定的定制接口。

0. 项目结构搭建

bash
复制代码npx create-react-app test-MA --template=typescript
rm -rf src/*
cd src/
touch app.tsx index.css index.tsx logo.svg MA.tsx

1. 包装组件MA的接口

ts
复制代码type IProps = {
  main: string;
  auxiliary: string;
  content: (props: any)=> JSX.Element;
  mainStyle: Record<string, string|number>;
  auxiliaryStyle: Record<string, string|number>;
}

2. 待渲染组件M的接口

ts
复制代码type IMProps = {
  id: string;
  content: (props: any)=> JSX.Element;
  style: Record<string, string|number>;
}

3. 待渲染组件M

ts
复制代码const M = (props: IMProps) => {
  const {id, content:C, style} = props;
  const target = document.getElementById(id);
  
  if(target) {
    return ReactDOM.createPortal(
      React.createElement(C, {style}), // 这样做的目的是为了在渲染content组件的时候传递参数
      target,
    );
  } else {
    return <></>;
  }
}

4. 包装组件MA

ts
复制代码function MA(props: IProps) {
  const {main: m, auxiliary: a, content:c, mainStyle: mS, auxiliaryStyle: aS} = props;
  
  return (
    <>
      <M id={m} content={c} style={mS} />
      <M id={a} content={c} style={aS} />
    </>
  );
}

5. 容器构造以及MA的使用

ts
复制代码const root = ReactDOM.createRoot(
  document.getElementById('root') as HTMLElement
);
root.render(
  <>
    <div
      id='main-view'
    ></div>
    <div
      id='auxiliary-view'
    ></div>
    <MA
      main='main-view'
      auxiliary='auxiliary-view'
      content={App}
      mainStyle={{color:'red'}}
      auxiliaryStyle={{color:'blue'}}
    />
    
  </>
);

6. 主视图和缩略图的样式

css
复制代码#main-view {
  position: absolute;
  overflow: hidden;
  width: 500px;
  height: 500px;
  top: 100px;
  left: 100px;
}

#auxiliary-view {
  position: absolute;
  overflow: hidden;
  width: 100px;
  height: 100px;
  bottom: 100px;
  right: 100px;
}

7. 被渲染的组件App

ts
复制代码import React from 'react';
import logo from './logo.svg';

type IProps = {
  style: Record<string, string | number>;
}

function App(props: IProps) {
  const { style:{color='black'} } = props;
  return (
        <img style={{width: '100%', border: `1px solid ${color}`}} src={logo} alt="logo" />
  );
}

export default App;

8. 各个文件内容

app.tsx

tsx
复制代码import React from 'react';
import logo from './logo.svg';

type IProps = {
  style: Record<string, string | number>;
}

function App(props: IProps) {
  const { style:{color='black'} } = props;
  return (
        <img style={{width: '100%', border: `1px solid ${color}`}} src={logo} alt="logo" />
  );
}

export default App;

index.css

css
复制代码#main-view {
  position: absolute;
  overflow: hidden;
  width: 500px;
  height: 500px;
  top: 100px;
  left: 100px;
}

#auxiliary-view {
  position: absolute;
  overflow: hidden;
  width: 100px;
  height: 100px;
  bottom: 100px;
  right: 100px;
}

index.tsx

tsx
复制代码/// <reference types="react-scripts" />
import React from 'react';
import ReactDOM from 'react-dom/client';
import './index.css';
import App from './App';
import MA from './MA';

const root = ReactDOM.createRoot(
  document.getElementById('root') as HTMLElement
);
root.render(
  <>
    <div
      id='main-view'
    ></div>
    <div
      id='auxiliary-view'
    ></div>
    <MA
      main='main-view'
      auxiliary='auxiliary-view'
      content={App}
      mainStyle={{color:'red'}}
      auxiliaryStyle={{color:'blue'}}
    />
  </>
);

logo.svg

xml
复制代码<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 841.9 595.3"><g fill="#61DAFB"><path d="M666.3 296.5c0-32.5-40.7-63.3-103.1-82.4 14.4-63.6 8-114.2-20.2-130.4-6.5-3.8-14.1-5.6-22.4-5.6v22.3c4.6 0 8.3.9 11.4 2.6 13.6 7.8 19.5 37.5 14.9 75.7-1.1 9.4-2.9 19.3-5.1 29.4-19.6-4.8-41-8.5-63.5-10.9-13.5-18.5-27.5-35.3-41.6-50 32.6-30.3 63.2-46.9 84-46.9V78c-27.5 0-63.5 19.6-99.9 53.6-36.4-33.8-72.4-53.2-99.9-53.2v22.3c20.7 0 51.4 16.5 84 46.6-14 14.7-28 31.4-41.3 49.9-22.6 2.4-44 6.1-63.6 11-2.3-10-4-19.7-5.2-29-4.7-38.2 1.1-67.9 14.6-75.8 3-1.8 6.9-2.6 11.5-2.6V78.5c-8.4 0-16 1.8-22.6 5.6-28.1 16.2-34.4 66.7-19.9 130.1-62.2 19.2-102.7 49.9-102.7 82.3 0 32.5 40.7 63.3 103.1 82.4-14.4 63.6-8 114.2 20.2 130.4 6.5 3.8 14.1 5.6 22.5 5.6 27.5 0 63.5-19.6 99.9-53.6 36.4 33.8 72.4 53.2 99.9 53.2 8.4 0 16-1.8 22.6-5.6 28.1-16.2 34.4-66.7 19.9-130.1 62-19.1 102.5-49.9 102.5-82.3zm-130.2-66.7c-3.7 12.9-8.3 26.2-13.5 39.5-4.1-8-8.4-16-13.1-24-4.6-8-9.5-15.8-14.4-23.4 14.2 2.1 27.9 4.7 41 7.9zm-45.8 106.5c-7.8 13.5-15.8 26.3-24.1 38.2-14.9 1.3-30 2-45.2 2-15.1 0-30.2-.7-45-1.9-8.3-11.9-16.4-24.6-24.2-38-7.6-13.1-14.5-26.4-20.8-39.8 6.2-13.4 13.2-26.8 20.7-39.9 7.8-13.5 15.8-26.3 24.1-38.2 14.9-1.3 30-2 45.2-2 15.1 0 30.2.7 45 1.9 8.3 11.9 16.4 24.6 24.2 38 7.6 13.1 14.5 26.4 20.8 39.8-6.3 13.4-13.2 26.8-20.7 39.9zm32.3-13c5.4 13.4 10 26.8 13.8 39.8-13.1 3.2-26.9 5.9-41.2 8 4.9-7.7 9.8-15.6 14.4-23.7 4.6-8 8.9-16.1 13-24.1zM421.2 430c-9.3-9.6-18.6-20.3-27.8-32 9 .4 18.2.7 27.5.7 9.4 0 18.7-.2 27.8-.7-9 11.7-18.3 22.4-27.5 32zm-74.4-58.9c-14.2-2.1-27.9-4.7-41-7.9 3.7-12.9 8.3-26.2 13.5-39.5 4.1 8 8.4 16 13.1 24 4.7 8 9.5 15.8 14.4 23.4zM420.7 163c9.3 9.6 18.6 20.3 27.8 32-9-.4-18.2-.7-27.5-.7-9.4 0-18.7.2-27.8.7 9-11.7 18.3-22.4 27.5-32zm-74 58.9c-4.9 7.7-9.8 15.6-14.4 23.7-4.6 8-8.9 16-13 24-5.4-13.4-10-26.8-13.8-39.8 13.1-3.1 26.9-5.8 41.2-7.9zm-90.5 125.2c-35.4-15.1-58.3-34.9-58.3-50.6 0-15.7 22.9-35.6 58.3-50.6 8.6-3.7 18-7 27.7-10.1 5.7 19.6 13.2 40 22.5 60.9-9.2 20.8-16.6 41.1-22.2 60.6-9.9-3.1-19.3-6.5-28-10.2zM310 490c-13.6-7.8-19.5-37.5-14.9-75.7 1.1-9.4 2.9-19.3 5.1-29.4 19.6 4.8 41 8.5 63.5 10.9 13.5 18.5 27.5 35.3 41.6 50-32.6 30.3-63.2 46.9-84 46.9-4.5-.1-8.3-1-11.3-2.7zm237.2-76.2c4.7 38.2-1.1 67.9-14.6 75.8-3 1.8-6.9 2.6-11.5 2.6-20.7 0-51.4-16.5-84-46.6 14-14.7 28-31.4 41.3-49.9 22.6-2.4 44-6.1 63.6-11 2.3 10.1 4.1 19.8 5.2 29.1zm38.5-66.7c-8.6 3.7-18 7-27.7 10.1-5.7-19.6-13.2-40-22.5-60.9 9.2-20.8 16.6-41.1 22.2-60.6 9.9 3.1 19.3 6.5 28.1 10.2 35.4 15.1 58.3 34.9 58.3 50.6-.1 15.7-23 35.6-58.4 50.6zM320.8 78.4z"/><circle cx="420.9" cy="296.5" r="45.7"/><path d="M520.5 78.1z"/></g></svg>

MA.tsx

tsx
复制代码import React from 'react';
import ReactDOM from 'react-dom';

type IProps = {
  main: string;
  auxiliary: string;
  content: (props: any)=> JSX.Element;
  mainStyle: Record<string, string|number>;
  auxiliaryStyle: Record<string, string|number>;
}


type IMProps = {
  id: string;
  content: (props: any)=> JSX.Element;
  style: Record<string, string|number>;
}

const M = (props: IMProps) => {
  const {id, content:C, style} = props;
  const target = document.getElementById(id);
  
  if(target) {
    return ReactDOM.createPortal(
      React.createElement(C, {style}),
      target,
    );
  } else {
    return <></>;
  }

}

function MA(props: IProps) {
  const {main: m, auxiliary: a, content:c, mainStyle: mS, auxiliaryStyle: aS} = props;
   
  return (
    <>
      <M id={m} content={c} style={mS} />
      <M id={a} content={c} style={aS} />
    </>
  );
}

export default MA;