Backend API
        
    import React, { useCallback, useState } from 'react';
import FileManager, {
  Permissions, ItemView, type FileManagerTypes, IItemViewProps,
} from 'devextreme-react/file-manager';
import { fileItems } from './data.ts';
export default function App() {
  const [itemViewMode, setItemViewMode] = useState<IItemViewProps['mode']>('thumbnails');
  const onOptionChanged = useCallback((e: FileManagerTypes.OptionChangedEvent) => {
    if (e.fullName === 'itemView.mode') {
      setItemViewMode(e.value);
    }
  }, [setItemViewMode]);
  const customizeIcon = useCallback<FileManagerTypes.Properties['customizeThumbnail']>((fileSystemItem) => {
    if (fileSystemItem.isDirectory) {
      return '../../../../images/thumbnails/folder.svg';
    }
    const fileExtension = fileSystemItem.getFileExtension();
    switch (fileExtension) {
      case '.txt':
        return '../../../../images/thumbnails/doc-txt.svg';
      case '.rtf':
        return '../../../../images/thumbnails/doc-rtf.svg';
      case '.xml':
        return '../../../../images/thumbnails/doc-xml.svg';
      default:
        return '../../../../images/thumbnails/doc-txt.svg';
    }
  }, []);
  return (
    <FileManager
      fileSystemProvider={fileItems}
      customizeThumbnail={customizeIcon}
      height={450}
      onOptionChanged={onOptionChanged}
    >
      <ItemView mode={itemViewMode} />
      <Permissions
        create={true}
        copy={true}
        move={true}
        delete={true}
        rename={true}
        upload={true}
        download={true}
      />
    </FileManager>
  );
}
    
    import React, { useCallback, useState } from 'react';
import FileManager, { Permissions, ItemView } from 'devextreme-react/file-manager';
import { fileItems } from './data.js';
export default function App() {
  const [itemViewMode, setItemViewMode] = useState('thumbnails');
  const onOptionChanged = useCallback(
    (e) => {
      if (e.fullName === 'itemView.mode') {
        setItemViewMode(e.value);
      }
    },
    [setItemViewMode],
  );
  const customizeIcon = useCallback((fileSystemItem) => {
    if (fileSystemItem.isDirectory) {
      return '../../../../images/thumbnails/folder.svg';
    }
    const fileExtension = fileSystemItem.getFileExtension();
    switch (fileExtension) {
      case '.txt':
        return '../../../../images/thumbnails/doc-txt.svg';
      case '.rtf':
        return '../../../../images/thumbnails/doc-rtf.svg';
      case '.xml':
        return '../../../../images/thumbnails/doc-xml.svg';
      default:
        return '../../../../images/thumbnails/doc-txt.svg';
    }
  }, []);
  return (
    <FileManager
      fileSystemProvider={fileItems}
      customizeThumbnail={customizeIcon}
      height={450}
      onOptionChanged={onOptionChanged}
    >
      <ItemView mode={itemViewMode} />
      <Permissions
        create={true}
        copy={true}
        move={true}
        delete={true}
        rename={true}
        upload={true}
        download={true}
      />
    </FileManager>
  );
}
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.tsx';
ReactDOM.render(
  <App />,
  document.getElementById('app'),
);
    
    export const fileItems = [{
  name: 'Documents',
  isDirectory: true,
  items: [{
    name: 'Projects',
    isDirectory: true,
    items: [{
      name: 'About.rtf',
      isDirectory: false,
      size: 1024,
    }, {
      name: 'Passwords.rtf',
      isDirectory: false,
      size: 2048,
    }],
  }, {
    name: 'About.xml',
    isDirectory: false,
    size: 1024,
  }, {
    name: 'Managers.rtf',
    isDirectory: false,
    size: 2048,
  }, {
    name: 'ToDo.txt',
    isDirectory: false,
    size: 3072,
  }],
}, {
  name: 'Images',
  isDirectory: true,
  items: [{
    name: 'logo.png',
    isDirectory: false,
    size: 20480,
  }, {
    name: 'banner.gif',
    isDirectory: false,
    size: 10240,
  }],
}, {
  name: 'System',
  isDirectory: true,
  items: [{
    name: 'Employees.txt',
    isDirectory: false,
    size: 3072,
  }, {
    name: 'PasswordList.txt',
    isDirectory: false,
    size: 5120,
  }],
}, {
  name: 'Description.rtf',
  isDirectory: false,
  size: 1024,
}, {
  name: 'Description.txt',
  isDirectory: false,
  size: 2048,
}];
    
    window.exports = window.exports || {};
window.config = {
  transpiler: 'ts',
  typescriptOptions: {
    module: 'system',
    emitDecoratorMetadata: true,
    experimentalDecorators: true,
    jsx: 'react',
  },
  meta: {
    'react': {
      'esModule': true,
    },
    'typescript': {
      'exports': 'ts',
    },
    'devextreme/time_zone_utils.js': {
      'esModule': true,
    },
    'devextreme/localization.js': {
      'esModule': true,
    },
    'devextreme/viz/palette.js': {
      'esModule': true,
    },
    'openai': {
      'esModule': true,
    },
  },
  paths: {
    'npm:': 'https://cdn.jsdelivr.net/npm/',
    'bundles:': '../../../../bundles/',
    'externals:': '../../../../bundles/externals/',
  },
  defaultExtension: 'js',
  map: {
    'ts': 'npm:plugin-typescript@8.0.0/lib/plugin.js',
    'typescript': 'npm:typescript@4.2.4/lib/typescript.js',
    'jszip': 'npm:jszip@3.10.1/dist/jszip.min.js',
    'react': 'npm:react@17.0.2/umd/react.development.js',
    'react-dom': 'npm:react-dom@17.0.2/umd/react-dom.development.js',
    'prop-types': 'npm:prop-types/prop-types.js',
    'rrule': 'npm:rrule@2.6.4/dist/es5/rrule.js',
    'luxon': 'npm:luxon@3.4.4/build/global/luxon.min.js',
    'es6-object-assign': 'npm:es6-object-assign',
    'devextreme': 'npm:devextreme@link:../../packages/devextreme/artifacts/npm/devextreme/cjs',
    'devextreme-react': 'npm:devextreme-react@link:../../packages/devextreme-react/npm/cjs',
    'devextreme-quill': 'npm:devextreme-quill@1.7.6/dist/dx-quill.min.js',
    'devexpress-diagram': 'npm:devexpress-diagram@2.2.24/dist/dx-diagram.js',
    'devexpress-gantt': 'npm:devexpress-gantt@4.1.64/dist/dx-gantt.js',
    'inferno': 'npm:inferno@8.2.3/dist/inferno.min.js',
    'inferno-compat': 'npm:inferno-compat/dist/inferno-compat.min.js',
    'inferno-create-element': 'npm:inferno-create-element@8.2.3/dist/inferno-create-element.min.js',
    'inferno-dom': 'npm:inferno-dom/dist/inferno-dom.min.js',
    'inferno-hydrate': 'npm:inferno-hydrate/dist/inferno-hydrate.min.js',
    'inferno-clone-vnode': 'npm:inferno-clone-vnode/dist/inferno-clone-vnode.min.js',
    'inferno-create-class': 'npm:inferno-create-class/dist/inferno-create-class.min.js',
    'inferno-extras': 'npm:inferno-extras/dist/inferno-extras.min.js',
    '@preact/signals-core': 'npm:@preact/signals-core@1.8.0/dist/signals-core.min.js',
    'devextreme-cldr-data': 'npm:devextreme-cldr-data@1.0.3',
    // SystemJS plugins
    'plugin-babel': 'npm:systemjs-plugin-babel@0.0.25/plugin-babel.js',
    'systemjs-babel-build': 'npm:systemjs-plugin-babel@0.0.25/systemjs-babel-browser.js',
    // Prettier
    'prettier/standalone': 'npm:prettier@2.8.8/standalone.js',
    'prettier/parser-html': 'npm:prettier@2.8.8/parser-html.js',
  },
  packages: {
    'devextreme': {
      defaultExtension: 'js',
    },
    'devextreme-react': {
      main: 'index.js',
    },
    'devextreme-react/common': {
      main: 'index.js',
    },
    'devextreme/events/utils': {
      main: 'index',
    },
    'devextreme/common/core/events/utils': {
      main: 'index',
    },
    'devextreme/localization/messages': {
      format: 'json',
      defaultExtension: 'json',
    },
    'devextreme/events': {
      main: 'index',
    },
    'es6-object-assign': {
      main: './index.js',
      defaultExtension: 'js',
    },
  },
  packageConfigPaths: [
    'npm:@devextreme/*/package.json',
  ],
  babelOptions: {
    sourceMaps: false,
    stage0: true,
    react: true,
  },
};
System.config(window.config);
// eslint-disable-next-line
const useTgzInCSB = ['openai'];
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.js';
ReactDOM.render(<App />, document.getElementById('app'));
    
    export const fileItems = [
  {
    name: 'Documents',
    isDirectory: true,
    items: [
      {
        name: 'Projects',
        isDirectory: true,
        items: [
          {
            name: 'About.rtf',
            isDirectory: false,
            size: 1024,
          },
          {
            name: 'Passwords.rtf',
            isDirectory: false,
            size: 2048,
          },
        ],
      },
      {
        name: 'About.xml',
        isDirectory: false,
        size: 1024,
      },
      {
        name: 'Managers.rtf',
        isDirectory: false,
        size: 2048,
      },
      {
        name: 'ToDo.txt',
        isDirectory: false,
        size: 3072,
      },
    ],
  },
  {
    name: 'Images',
    isDirectory: true,
    items: [
      {
        name: 'logo.png',
        isDirectory: false,
        size: 20480,
      },
      {
        name: 'banner.gif',
        isDirectory: false,
        size: 10240,
      },
    ],
  },
  {
    name: 'System',
    isDirectory: true,
    items: [
      {
        name: 'Employees.txt',
        isDirectory: false,
        size: 3072,
      },
      {
        name: 'PasswordList.txt',
        isDirectory: false,
        size: 5120,
      },
    ],
  },
  {
    name: 'Description.rtf',
    isDirectory: false,
    size: 1024,
  },
  {
    name: 'Description.txt',
    isDirectory: false,
    size: 2048,
  },
];
    
    <!DOCTYPE html>
<html lang="en">
  <head>
    <title>DevExtreme Demo</title>
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0" />
    <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/25.1.6/css/dx.light.css" />
    <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/25.1.6/css/dx-gantt.min.css" />
    <script src="https://cdn.jsdelivr.net/npm/core-js@2.6.12/client/shim.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/systemjs@0.21.3/dist/system.js"></script>
    <script type="text/javascript" src="config.js"></script>
    <script type="text/javascript">
      System.import("./index.tsx");
    </script>
      <link rel="stylesheet" type="text/css" href="styles.css" />
</head>
  <body class="dx-viewport">
    <div class="demo-container">
      <div id="app"></div>
    </div>
  </body>
</html>