import CKEditor from '@ckeditor/ckeditor5-react';
import ClassicEditor from '@ckeditor/ckeditor5-build-classic';
import '@ckeditor/ckeditor5-build-classic/build/translations/ja';

<CKEditor
  editor={ClassicEditor}
  config={{
    language: 'ja',
  }}
/>

  componentWillReceiveProps(newProps) {
    if (this.editorInstance && newProps.data) {
      this.editorInstance.setData(newProps.data);
    }
  }

import Font from "@ckeditor/ckeditor5-font/src/font";

<CKEditor
    editor={ClassicEditor}
    data={this.props.value}
    onInit={(editor) => {
      console.log(editor);
    }}
    config={{
       plugins: [Font],
       toolbar: ["fontSize", "fontFamily"],
    }}
     onChange={(event, editor) => {
       this.onEditorChange(event, editor);
    }}
/>

ckeditor.js:5 TypeError: Cannot read property 'getAttribute' of null
    at IconView._updateXMLContent (iconview.js:100)
    at IconView.render (iconview.js:76)
    at IconView.on (observablemixin.js:249)
    at IconView.fire (emittermixin.js:196)
    at IconView.(anonymous function) [as render] (http://localhost:3030/js/bundle.js:27142:16)
    at ViewCollection.on (viewcollection.js:68)
    at ViewCollection.fire (emittermixin.js:196)
    at ViewCollection.add (collection.js:182)
    at DropdownButtonView.render (buttonview.js:168)
    at DropdownButtonView.render (dropdownbuttonview.js:64)

const path = require("path");
const webpack = require("webpack");
const { styles } = require("@ckeditor/ckeditor5-dev-utils");

module.exports = {
  devtool: "cheap-module-source-map",
  entry: ["webpack-hot-middleware/client", "./dev/js/index"],
  output: {
    path: path.join(__dirname, "dist/js"),
    publicPath: "/js/",
    filename: "bundle.js",
  },
  module: {
    loaders: [
      {
        loader: require.resolve("file-loader"),
        // Exclude `js` files to keep the "css" loader working as it injects
        // its runtime that would otherwise be processed through the "file" loader.
        // Also exclude `html` and `json` extensions so they get processed
        // by webpack's internal loaders.
        exclude: [
          /ckeditor5-[^/\\]+[/\\]theme[/\\]icons[/\\][^/\\]+\.svg$/,
          /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css/,
        ],
        options: {
          name: "static/media/[name].[hash:8].[ext]",
        },
      },
      {
        test: /ckeditor5-[^/\\]+[/\\]theme[/\\]icons[/\\][^/\\]+\.svg$/,
        use: ["raw-loader"],
      },
      {
        test: /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css/,
        use: [
          {
            loader: "style-loader",
            options: {
              singleton: true,
            },
          },
          {
            loader: "postcss-loader",
            options: styles.getPostCssConfig({
              themeImporter: {
                themePath: require.resolve("@ckeditor/ckeditor5-theme-lark"),
              },
              minify: true,
            }),
          },
        ],
      },
      {
        test: /\.js$/,
        include: path.join(__dirname, "dev/js"),
        exclude: /node_modules/,
        loader: "babel-loader",
        options: {
          presets: ["react", "es2015", "stage-0"],
        },
      },
      {
        test: /\.(sass|scss)/,
        include: path.join(__dirname, "dev/sass"),
        loader: "style-loader!css-loader!sass-loader",
      },
      {
        test: /\.css$/,
        exclude: /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css/,
        loader: "style-loader!css-loader",
      },
      {
        test: /\.(otf|ttf|eot|svg|woff(2)?)(\?[a-z0-9=&.]+)?$/,
        loaders: ["url-loader"],
      },
      {
        test: /\.(png|jpg)$/,
        loader: "url-loader",
      },
    ],
  },
  plugins: [
    new webpack.HotModuleReplacementPlugin(),
    new webpack.NoEmitOnErrorsPlugin(),
    new webpack.DefinePlugin({
      "process.env": {
        NODE_ENV: JSON.stringify("development"),
      },
    }),
  ],
};

...
import CKEditor from "cke5-react/src/ckeditor";
import ClassicEditorBuild from "@ckeditor/ckeditor5-build-classic";
...

_initializeEditor() {
    const { editor, config, data, onInit, onChange, autoFocus } = this.props;
...
if (autoFocus) this.editorInstance.editing.view.focus();

import React, {Component} from 'react'
import CKEditor from '@ckeditor/ckeditor5-react'

import InlineEditor from '@ckeditor/ckeditor5-build-inline'
/** Essentials, Heading, Paragraph, Bold, Italic, BlockQuote, Alignment, List, Link **/

import Alignment from '@ckeditor/ckeditor5-alignment/src/alignment'
import Essentials from '@ckeditor/ckeditor5-essentials/src/essentials'
import Heading from '@ckeditor/ckeditor5-heading/src/heading'
import Paragraph from '@ckeditor/ckeditor5-paragraph/src/paragraph'
import Bold from '@ckeditor/ckeditor5-basic-styles/src/bold'
import Italic from '@ckeditor/ckeditor5-basic-styles/src/italic'
import BlockQuote from '@ckeditor/ckeditor5-block-quote/src/blockquote'
import List from '@ckeditor/ckeditor5-list/src/list'
import Link from '@ckeditor/ckeditor5-link/src/link'

export default class MyComponent extends Component {
  handleEditorChange = () => {} //TO-DO: Write event handler
  render(){
    return (
      <div style={{height: '100%'}}>
        <CKEditor
          config={{
            plugins: [Essentials, Heading, Paragraph, Bold, Italic, BlockQuote, Alignment, List, Link],
            toolbar: ['Heading', '|', 'Bold', 'Italic', 'Alignment', 'Link', 'List', 'ListUI', 'BlockQuote', 'Undo', 'Redo'],
            removePlugins: ['Image', 'ImageCaption', 'ImageStyle', 'ImageToolbar', 'ImageUpload']
          }}
          editor={InlineEditor}
          data={this.state.content.value || ''}
          onChange={this.handleEditorChange}
        />
      </div>
    )
  }
}

import * as React from 'react';
import { HashRouter} from 'react-router-dom';
import CKEditor from '@ckeditor/ckeditor5-react';
import BalloonEditor from '@ckeditor/ckeditor5-build-classic';


export class Main extends React.Component {
    constructor(props) {
        //console.log( ' IN THE Constructor' );
        super(props);
                
    }

    render() {
                return (
            
            <HashRouter>
                <div className="container d-flex flex-column">
                    <div>CKEditor:
                        
                    <CKEditor editor={BalloonEditor} data={'Test Test Test'}
                    />
                    </div>

                </div>
            </HashRouter>
        );

    }

}

'use strict';

const autoprefixer = require('autoprefixer');
const path = require('path');
const webpack = require('webpack');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CaseSensitivePathsPlugin = require('case-sensitive-paths-webpack-plugin');
const InterpolateHtmlPlugin = require('react-dev-utils/InterpolateHtmlPlugin');
const WatchMissingNodeModulesPlugin = require('react-dev-utils/WatchMissingNodeModulesPlugin');
const eslintFormatter = require('react-dev-utils/eslintFormatter');
const ModuleScopePlugin = require('react-dev-utils/ModuleScopePlugin');
const getClientEnvironment = require('./env');
const paths = require('./paths');

const { styles } = require('@ckeditor/ckeditor5-dev-utils');
const UglifyJsWebpackPlugin = require('uglifyjs-webpack-plugin');

// Webpack uses `publicPath` to determine where the app is being served from.
// In development, we always serve from the root. This makes config easier.
const publicPath = '/';
// `publicUrl` is just like `publicPath`, but we will provide it to our app
// as %PUBLIC_URL% in `index.html` and `process.env.PUBLIC_URL` in JavaScript.
// Omit trailing slash as %PUBLIC_PATH%/xyz looks better than %PUBLIC_PATH%xyz.
const publicUrl = '';
// Get environment variables to inject into our app.
const env = getClientEnvironment(publicUrl);

// This is the development configuration.
// It is focused on developer experience and fast rebuilds.
// The production configuration is different and lives in a separate file.
module.exports = {
  // You may want 'eval' instead if you prefer to see the compiled output in DevTools.
  // See the discussion in https://github.com/facebookincubator/create-react-app/issues/343.
  devtool: 'cheap-module-source-map',
  // These are the "entry points" to our application.
  // This means they will be the "root" imports that are included in JS bundle.
  // The first two entry points enable "hot" CSS and auto-refreshes for JS.
  entry: [
    // We ship a few polyfills by default:
    require.resolve('./polyfills'),
    // Include an alternative client for WebpackDevServer. A client's job is to
    // connect to WebpackDevServer by a socket and get notified about changes.
    // When you save a file, the client will either apply hot updates (in case
    // of CSS changes), or refresh the page (in case of JS changes). When you
    // make a syntax error, this client will display a syntax error overlay.
    // Note: instead of the default WebpackDevServer client, we use a custom one
    // to bring better experience for Create React App users. You can replace
    // the line below with these two lines if you prefer the stock client:
    // require.resolve('webpack-dev-server/client') + '?/',
    // require.resolve('webpack/hot/dev-server'),
    require.resolve('react-dev-utils/webpackHotDevClient'),
    // Finally, this is your app's code:
    paths.appIndexJs
    // We include the app code last so that if there is a runtime error during
    // initialization, it doesn't blow up the WebpackDevServer client, and
    // changing JS code would still trigger a refresh.
  ],
  output: {
    // Add /* filename */ comments to generated require()s in the output.
    pathinfo: true,
    // This does not produce a real file. It's just the virtual path that is
    // served by WebpackDevServer in development. This is the JS bundle
    // containing code from all our entry points, and the Webpack runtime.
    filename: 'static/js/bundle.js',
    // There are also additional JS chunk files if you use code splitting.
    chunkFilename: 'static/js/[name].chunk.js',
    // This is the URL that app is served from. We use "/" in development.
    publicPath: publicPath,
    // Point sourcemap entries to original disk location (format as URL on Windows)
    devtoolModuleFilenameTemplate: info =>
      path.resolve(info.absoluteResourcePath).replace(/\\/g, '/')
  },
  resolve: {
    // This allows you to set a fallback for where Webpack should look for modules.
    // We placed these paths second because we want `node_modules` to "win"
    // if there are any conflicts. This matches Node resolution mechanism.
    // https://github.com/facebookincubator/create-react-app/issues/253
    modules: ['node_modules', paths.appNodeModules].concat(
      // It is guaranteed to exist because we tweak it in `env.js`
      process.env.NODE_PATH.split(path.delimiter).filter(Boolean)
    ),
    // These are the reasonable defaults supported by the Node ecosystem.
    // We also include JSX as a common component filename extension to support
    // some tools, although we do not recommend using it, see:
    // https://github.com/facebookincubator/create-react-app/issues/290
    // `web` extension prefixes have been added for better support
    // for React Native Web.
    extensions: ['.web.js', '.mjs', '.js', '.json', '.web.jsx', '.jsx'],
    alias: {
      // Support React Native Web
      // https://www.smashingmagazine.com/2016/08/a-glimpse-into-the-future-with-react-native-for-web/
      'react-native': 'react-native-web'
    },
    plugins: [
      // Prevents users from importing files from outside of src/ (or node_modules/).
      // This often causes confusion because we only process files within src/ with babel.
      // To fix this, we prevent you from importing files out of src/ -- if you'd like to,
      // please link the files into your node_modules/ and let module-resolution kick in.
      // Make sure your source files are compiled, as they will not be processed in any way.
      new ModuleScopePlugin(paths.appSrc, [paths.appPackageJson])
    ]
  },
  module: {
    strictExportPresence: true,
    rules: [
      // TODO: Disable require.ensure as it's not a standard language feature.
      // We are waiting for https://github.com/facebookincubator/create-react-app/issues/2176.
      // { parser: { requireEnsure: false } },

      // First, run the linter.
      // It's important to do this before Babel processes the JS.
      {
        test: /\.(js|jsx|mjs)$/,
        enforce: 'pre',
        use: [
          {
            options: {
              formatter: eslintFormatter,
              eslintPath: require.resolve('eslint')
            },
            loader: require.resolve('eslint-loader')
          }
        ],
        include: paths.appSrc
      },
      {
        // "oneOf" will traverse all following loaders until one will
        // match the requirements. When no loader matches it will fall
        // back to the "file" loader at the end of the loader list.
        oneOf: [
          // "url" loader works like "file" loader except that it embeds assets
          // smaller than specified limit in bytes as data URLs to avoid requests.
          // A missing `test` is equivalent to a match.
          {
            test: [/\.bmp$/, /\.gif$/, /\.jpe?g$/, /\.png$/],
            loader: require.resolve('url-loader'),
            options: {
              limit: 10000,
              name: 'static/media/[name].[hash:8].[ext]'
            }
          },
          // CKEditor5
          {
            test: /ckeditor5-[^/\\]+[/\\]theme[/\\]icons[/\\][^/\\]+\.svg$/,
            use: ['raw-loader']
          },
          {
            test: /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css/,
            use: [
              {
                loader: 'style-loader',
                options: {
                  singleton: true
                }
              },
              {
                loader: 'postcss-loader',
                options: styles.getPostCssConfig({
                  themeImporter: {
                    themePath: require.resolve('@ckeditor/ckeditor5-theme-lark')
                  },
                  minify: true
                })
              }
            ]
          },
          // Process JS with Babel.
          {
            test: /\.(js|jsx|mjs)$/,
            include: paths.appSrc,
            loader: require.resolve('babel-loader'),
            options: {
              // This is a feature of `babel-loader` for webpack (not Babel itself).
              // It enables caching results in ./node_modules/.cache/babel-loader/
              // directory for faster rebuilds.
              cacheDirectory: true
            }
          },
          // "postcss" loader applies autoprefixer to our CSS.
          // "css" loader resolves paths in CSS and adds assets as dependencies.
          // "style" loader turns CSS into JS modules that inject <style> tags.
          // In production, we use a plugin to extract that CSS to a file, but
          // in development "style" loader enables hot editing of CSS.
          {
            test: /\.css$/,
            exclude: /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css/,
            use: [
              require.resolve('style-loader'),
              {
                loader: require.resolve('css-loader'),
                options: {
                  importLoaders: 1
                }
              },
              {
                loader: require.resolve('postcss-loader'),
                options: {
                  // Necessary for external CSS imports to work
                  // https://github.com/facebookincubator/create-react-app/issues/2677
                  ident: 'postcss',
                  plugins: () => [
                    require('postcss-flexbugs-fixes'),
                    autoprefixer({
                      browsers: [
                        '>1%',
                        'last 4 versions',
                        'Firefox ESR',
                        'not ie < 9' // React doesn't support IE8 anyway
                      ],
                      flexbox: 'no-2009'
                    })
                  ]
                }
              }
            ]
          },
          // "file" loader makes sure those assets get served by WebpackDevServer.
          // When you `import` an asset, you get its (virtual) filename.
          // In production, they would get copied to the `build` folder.
          // This loader doesn't use a "test" so it will catch all modules
          // that fall through the other loaders.
          {
            // Exclude `js` files to keep "css" loader working as it injects
            // its runtime that would otherwise processed through "file" loader.
            // Also exclude `html` and `json` extensions so they get processed
            // by webpacks internal loaders.
            exclude: [
              /\.(js|jsx|mjs)$/,
              /\.html$/,
              /\.json$/,
              /ckeditor5-[^/\\]+[/\\]theme[/\\]icons[/\\][^/\\]+\.svg$/,
              /ckeditor5-[^/\\]+[/\\]theme[/\\].+\.css/
            ],
            loader: require.resolve('file-loader'),
            options: {
              name: 'static/media/[name].[hash:8].[ext]'
            }
          }
        ]
      }
      // ** STOP ** Are you adding a new loader?
      // Make sure to add the new loader(s) before the "file" loader.
    ]
  },
  plugins: [
    // Makes some environment variables available in index.html.
    // The public URL is available as %PUBLIC_URL% in index.html, e.g.:
    // <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
    // In development, this will be an empty string.
    new InterpolateHtmlPlugin(env.raw),
    // Generates an `index.html` file with the <script> injected.
    new HtmlWebpackPlugin({
      inject: true,
      template: paths.appHtml
    }),
    // For CKEditor 5
    new UglifyJsWebpackPlugin({
      uglifyOptions: {
        compress: {
          warnings: false,
          // Disabled because of an issue with Uglify breaking seemingly valid code:
          // https://github.com/facebookincubator/create-react-app/issues/2376
          // Pending further investigation:
          // https://github.com/mishoo/UglifyJS2/issues/2011
          comparisons: false
        },
        mangle: {
          safari10: true
        },
        output: {
          comments: false,
          // Turned on because emoji and regex is not minified properly using default
          // https://github.com/facebookincubator/create-react-app/issues/2488
          ascii_only: true
        }
      },
      // sourceMap: shouldUseSourceMap
      sourceMap: true
    }),

    // Add module names to factory functions so they appear in browser profiler.
    new webpack.NamedModulesPlugin(),
    // Makes some environment variables available to the JS code, for example:
    // if (process.env.NODE_ENV === 'development') { ... }. See `./env.js`.
    new webpack.DefinePlugin(env.stringified),
    // This is necessary to emit hot updates (currently CSS only):
    new webpack.HotModuleReplacementPlugin(),
    // Watcher doesn't work well if you mistype casing in a path so we use
    // a plugin that prints an error when you attempt to do this.
    // See https://github.com/facebookincubator/create-react-app/issues/240
    new CaseSensitivePathsPlugin(),
    // If you require a missing module and then `npm install` it, you still have
    // to restart the development server for Webpack to discover it. This plugin
    // makes the discovery automatic so you don't have to restart.
    // See https://github.com/facebookincubator/create-react-app/issues/186
    new WatchMissingNodeModulesPlugin(paths.appNodeModules),
    // Moment.js is an extremely popular library that bundles large locale files
    // by default due to how Webpack interprets its code. This is a practical
    // solution that requires the user to opt into importing specific locales.
    // https://github.com/jmblog/how-to-optimize-momentjs-with-webpack
    // You can remove this if you don't use Moment.js:
    new webpack.IgnorePlugin(/^\.\/locale$/, /moment$/)
  ],
  // Some libraries import Node modules but don't use them in the browser.
  // Tell Webpack to provide empty mocks for them so importing them works.
  node: {
    dgram: 'empty',
    fs: 'empty',
    net: 'empty',
    tls: 'empty',
    child_process: 'empty'
  },
  // Turn off performance hints during development because we don't do any
  // splitting or minification in interest of speed. These warnings become
  // cumbersome.
  performance: {
    hints: false
  }
};