create-react-app+typescript 搭建cesium開發環境

搭建開發環境

create-react-app + typescript + cesium

新建工程

1. 執行如下命令

create-react-app --typesctipt cesium-react-ts

2. 進入cesium-react-ts 目錄執行

yarn run eject

3. 執行yarn run start 測試項目是否安裝成功

如果報錯，刪除node_modules，重新安裝依賴

安裝cesium並配置

參考https://blog.csdn.net/qq_33484881/article/details/85336458 這篇博客進行配置，

錯誤處理

1. CESIUM_BASE_URL錯誤處理

App.tsx代碼如下：

import React, { Component } from 'react'
const Cesium: any = require('cesium/Cesium')

const initViewerOptions = {
  selectionIndicator: false,
  // shadows: true, // 陰影不顯示
  shouldAnimate: true,
  vrButton: false,
  animation: false, // 動畫控制不顯示
  baseLayerPicker: false, // 圖層控制顯示
  geocoder: false, // 地名查找不顯示
  timeline: false, // 時間線不顯示
  sceneModePicker: false, // 投影方式顯示
  sceen3DOnly: true,
  requestRenderMode: true,
  fullscreenButton: false,
  homeButton: false,
  infoBox: false,
  navigationHelpButton: false,
  contextOptions: {
    webgl: {
      alpha: true
    }
  }
}
class App extends Component {
  viewContainer: any
  componentDidMount() {
    const viewer = new Cesium.Viewer(this.viewContainer, initViewerOptions)
  }
  render() {
    return (
      <div id='cesiumContainer' ref={node => (this.viewContainer = node)} />
    )
  }
}

export default App

錯誤信息如下：

解決方案：
修改config/env.js如下：

'use strict';

const fs = require('fs');
const path = require('path');
const paths = require('./paths');

// Make sure that including paths.js after env.js will read .env variables.
delete require.cache[require.resolve('./paths')];

const NODE_ENV = process.env.NODE_ENV;
if (!NODE_ENV) {
  throw new Error(
    'The NODE_ENV environment variable is required but was not specified.'
  );
}

// https://github.com/bkeepers/dotenv#what-other-env-files-can-i-use
const dotenvFiles = [
  `${paths.dotenv}.${NODE_ENV}.local`,
  `${paths.dotenv}.${NODE_ENV}`,
  // Don't include `.env.local` for `test` environment
  // since normally you expect tests to produce the same
  // results for everyone
  NODE_ENV !== 'test' && `${paths.dotenv}.local`,
  paths.dotenv,
].filter(Boolean);

// Load environment variables from .env* files. Suppress warnings using silent
// if this file is missing. dotenv will never modify any environment variables
// that have already been set.  Variable expansion is supported in .env files.
// https://github.com/motdotla/dotenv
// https://github.com/motdotla/dotenv-expand
dotenvFiles.forEach(dotenvFile => {
  if (fs.existsSync(dotenvFile)) {
    require('dotenv-expand')(
      require('dotenv').config({
        path: dotenvFile,
      })
    );
  }
});

// We support resolving modules according to `NODE_PATH`.
// This lets you use absolute paths in imports inside large monorepos:
// https://github.com/facebook/create-react-app/issues/253.
// It works similar to `NODE_PATH` in Node itself:
// https://nodejs.org/api/modules.html#modules_loading_from_the_global_folders
// Note that unlike in Node, only *relative* paths from `NODE_PATH` are honored.
// Otherwise, we risk importing Node.js core modules into an app instead of Webpack shims.
// https://github.com/facebook/create-react-app/issues/1023#issuecomment-265344421
// We also resolve them to make sure all tools using them work consistently.
const appDirectory = fs.realpathSync(process.cwd());
process.env.NODE_PATH = (process.env.NODE_PATH || '')
  .split(path.delimiter)
  .filter(folder => folder && !path.isAbsolute(folder))
  .map(folder => path.resolve(appDirectory, folder))
  .join(path.delimiter);

// Grab NODE_ENV and REACT_APP_* environment variables and prepare them to be
// injected into the application via DefinePlugin in Webpack configuration.
const REACT_APP = /^REACT_APP_/i;

function getClientEnvironment(publicUrl) {
  const raw = Object.keys(process.env)
    .filter(key => REACT_APP.test(key))
    .reduce(
      (env, key) => {
        env[key] = process.env[key];
        return env;
      },
      {
        // Useful for determining whether we’re running in production mode.
        // Most importantly, it switches React into the correct mode.
        NODE_ENV: process.env.NODE_ENV || 'development',
        // Useful for resolving the correct path to static assets in `public`.
        // For example, <img src={process.env.PUBLIC_URL + '/img/logo.png'} />.
        // This should only be used as an escape hatch. Normally you would put
        // images into the `src` and `import` them in code to get their paths.
        PUBLIC_URL: publicUrl,
      }
    );
  // Stringify all values so we can feed into Webpack DefinePlugin
  const stringified = {
    'process.env': Object.keys(raw).reduce((env, key) => {
      env[key] = JSON.stringify(raw[key]);
      return env;
    }, {}),
    CESIUM_BASE_URL:JSON.stringify('')
  };

  return { raw, stringified };
}

module.exports = getClientEnvironment;

2. _Critical dependency _

解決方法：
在Webpack的module中配置如下：

module: {
// ...
//解決Critical dependency: require function is used in a way in which dependencies cannot be statically extracted的問題
unknownContextCritical : false,
rules: [
// ...

參考：

1. https://blog.csdn.net/qq_33484881/article/details/85336458
2. https://www.jianshu.com/p/85917bcc023f
3. https://www.jianshu.com/p/e405bc23109f
4. https://www.sypopo.com/post/1z59Ly0Ar9/