Backend API
        
    import React, { useCallback, useRef } from 'react';
import FileManager, {
  Permissions, Toolbar, ContextMenu, Item, FileSelectionItem, ItemView, Details, Column, FileManagerRef
} from 'devextreme-react/file-manager';
import { fileItems, getItemInfo } from './data.ts';
export default function App() {
  const fileManagerRef = useRef<FileManagerRef>(null);
  const createFile = useCallback((
    fileExtension,
    directory = fileManagerRef.current.instance().getCurrentDirectory(),
  ) => {
    const newItem = {
      __KEY__: Date.now(),
      name: `New file${fileExtension}`,
      isDirectory: false,
      size: 0,
    };
    if (!directory.isDirectory) {
      return false;
    }
    let array = null;
    if (!directory.dataItem) {
      array = fileItems;
    } else {
      array = directory.dataItem.items;
      if (!array) {
        array = [];
        directory.dataItem.items = array;
      }
    }
    array.push(newItem);
    return true;
  }, []);
  const updateCategory = useCallback((newCategory, directory, viewArea: string) => {
    let items = null;
    if (viewArea === 'navPane') {
      items = [directory];
    } else {
      items = fileManagerRef.current.instance().getSelectedItems();
    }
    items.forEach((item: { dataItem: { category: any; }; }) => {
      if (item.dataItem) {
        item.dataItem.category = newCategory;
      }
    });
    return items.length > 0;
  }, []);
  const onItemClick = useCallback(({ itemData, viewArea, fileSystemItem }) => {
    let updated = false;
    const { extension, category } = getItemInfo(itemData.text);
    if (extension) {
      updated = createFile(extension, fileSystemItem);
    } else if (category !== undefined) {
      updated = updateCategory(category, fileSystemItem, viewArea);
    }
    if (updated) {
      fileManagerRef.current.instance().refresh();
    }
  }, [createFile, updateCategory]);
  const getNewFileMenuOptions = useCallback(() => ({
    items: [
      {
        text: 'Create new file',
        icon: 'plus',
        items: [
          {
            text: 'Text Document',
            extension: '.txt',
          },
          {
            text: 'RTF Document',
            extension: '.rtf',
          },
          {
            text: 'Spreadsheet',
            extension: '.xls',
          },
        ],
      },
    ],
    onItemClick,
  }), [onItemClick]);
  const getChangeCategoryMenuOptions = useCallback(() => ({
    items: [
      {
        text: 'Category',
        icon: 'tags',
        items: [
          {
            text: 'Work',
            category: 'Work',
          },
          {
            text: 'Important',
            category: 'Important',
          },
          {
            text: 'Home',
            category: 'Home',
          },
          {
            text: 'None',
            category: '',
          },
        ],
      },
    ],
    onItemClick,
  }), [onItemClick]);
  return (
    <FileManager
      ref={fileManagerRef}
      fileSystemProvider={fileItems}
      onContextMenuItemClick={onItemClick}
      height={450}>
      <Permissions
        create={true}
        delete={true}
        rename={true}
        download={true}>
      </Permissions>
      <ItemView showParentFolder={false}>
        <Details>
          <Column dataField="thumbnail"></Column>
          <Column dataField="name"></Column>
          <Column dataField="category" caption="Category" width="95"></Column>
          <Column dataField="dateModified"></Column>
          <Column dataField="size"></Column>
        </Details>
      </ItemView>
      <Toolbar>
        <Item name="showNavPane" visible={true} />
        <Item name="separator" />
        <Item name="create" />
        <Item widget="dxMenu" location="before" options={getNewFileMenuOptions()} />
        <Item name="refresh" />
        <Item name="separator" location="after" />
        <Item name="switchView" />
        <FileSelectionItem name="rename" />
        <FileSelectionItem name="separator" />
        <FileSelectionItem name="delete" />
        <FileSelectionItem name="separator" />
        <FileSelectionItem widget="dxMenu" location="before" options={getChangeCategoryMenuOptions()} />
        <FileSelectionItem name="refresh" />
        <FileSelectionItem name="clearSelection" />
      </Toolbar>
      <ContextMenu>
        <Item name="create" />
        <Item text="Create new file" icon="plus">
          <Item text="Text Document" />
          <Item text="RTF Document" />
          <Item text="Spreadsheet" />
        </Item>
        <Item name="rename" beginGroup />
        <Item name="delete" />
        <Item text="Category" icon="tags" beginGroup>
          <Item text="Work" />
          <Item text="Important" />
          <Item text="Home" />
          <Item text="None" />
        </Item>
        <Item name="refresh" />
      </ContextMenu>
    </FileManager>
  );
}
    
    import React, { useCallback, useRef } from 'react';
import FileManager, {
  Permissions,
  Toolbar,
  ContextMenu,
  Item,
  FileSelectionItem,
  ItemView,
  Details,
  Column,
} from 'devextreme-react/file-manager';
import { fileItems, getItemInfo } from './data.js';
export default function App() {
  const fileManagerRef = useRef(null);
  const createFile = useCallback((fileExtension, directory = fileManagerRef.current
    .instance()
    .getCurrentDirectory()) => {
    const newItem = {
      __KEY__: Date.now(),
      name: `New file${fileExtension}`,
      isDirectory: false,
      size: 0,
    };
    if (!directory.isDirectory) {
      return false;
    }
    let array = null;
    if (!directory.dataItem) {
      array = fileItems;
    } else {
      array = directory.dataItem.items;
      if (!array) {
        array = [];
        directory.dataItem.items = array;
      }
    }
    array.push(newItem);
    return true;
  }, []);
  const updateCategory = useCallback((newCategory, directory, viewArea) => {
    let items = null;
    if (viewArea === 'navPane') {
      items = [directory];
    } else {
      items = fileManagerRef.current.instance().getSelectedItems();
    }
    items.forEach((item) => {
      if (item.dataItem) {
        item.dataItem.category = newCategory;
      }
    });
    return items.length > 0;
  }, []);
  const onItemClick = useCallback(
    ({ itemData, viewArea, fileSystemItem }) => {
      let updated = false;
      const { extension, category } = getItemInfo(itemData.text);
      if (extension) {
        updated = createFile(extension, fileSystemItem);
      } else if (category !== undefined) {
        updated = updateCategory(category, fileSystemItem, viewArea);
      }
      if (updated) {
        fileManagerRef.current.instance().refresh();
      }
    },
    [createFile, updateCategory],
  );
  const getNewFileMenuOptions = useCallback(
    () => ({
      items: [
        {
          text: 'Create new file',
          icon: 'plus',
          items: [
            {
              text: 'Text Document',
              extension: '.txt',
            },
            {
              text: 'RTF Document',
              extension: '.rtf',
            },
            {
              text: 'Spreadsheet',
              extension: '.xls',
            },
          ],
        },
      ],
      onItemClick,
    }),
    [onItemClick],
  );
  const getChangeCategoryMenuOptions = useCallback(
    () => ({
      items: [
        {
          text: 'Category',
          icon: 'tags',
          items: [
            {
              text: 'Work',
              category: 'Work',
            },
            {
              text: 'Important',
              category: 'Important',
            },
            {
              text: 'Home',
              category: 'Home',
            },
            {
              text: 'None',
              category: '',
            },
          ],
        },
      ],
      onItemClick,
    }),
    [onItemClick],
  );
  return (
    <FileManager
      ref={fileManagerRef}
      fileSystemProvider={fileItems}
      onContextMenuItemClick={onItemClick}
      height={450}
    >
      <Permissions
        create={true}
        delete={true}
        rename={true}
        download={true}
      ></Permissions>
      <ItemView showParentFolder={false}>
        <Details>
          <Column dataField="thumbnail"></Column>
          <Column dataField="name"></Column>
          <Column
            dataField="category"
            caption="Category"
            width="95"
          ></Column>
          <Column dataField="dateModified"></Column>
          <Column dataField="size"></Column>
        </Details>
      </ItemView>
      <Toolbar>
        <Item
          name="showNavPane"
          visible={true}
        />
        <Item name="separator" />
        <Item name="create" />
        <Item
          widget="dxMenu"
          location="before"
          options={getNewFileMenuOptions()}
        />
        <Item name="refresh" />
        <Item
          name="separator"
          location="after"
        />
        <Item name="switchView" />
        <FileSelectionItem name="rename" />
        <FileSelectionItem name="separator" />
        <FileSelectionItem name="delete" />
        <FileSelectionItem name="separator" />
        <FileSelectionItem
          widget="dxMenu"
          location="before"
          options={getChangeCategoryMenuOptions()}
        />
        <FileSelectionItem name="refresh" />
        <FileSelectionItem name="clearSelection" />
      </Toolbar>
      <ContextMenu>
        <Item name="create" />
        <Item
          text="Create new file"
          icon="plus"
        >
          <Item text="Text Document" />
          <Item text="RTF Document" />
          <Item text="Spreadsheet" />
        </Item>
        <Item
          name="rename"
          beginGroup
        />
        <Item name="delete" />
        <Item
          text="Category"
          icon="tags"
          beginGroup
        >
          <Item text="Work" />
          <Item text="Important" />
          <Item text="Home" />
          <Item text="None" />
        </Item>
        <Item name="refresh" />
      </ContextMenu>
    </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,
  category: 'Work',
  items: [{
    name: 'Projects',
    isDirectory: true,
    category: 'Work',
    items: [{
      name: 'About.rtf',
      isDirectory: false,
      size: 1024,
    }, {
      name: 'Passwords.rtf',
      isDirectory: false,
      category: 'Important',
      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,
  category: 'Home',
  items: [{
    name: 'logo.png',
    isDirectory: false,
    size: 20480,
  }, {
    name: 'banner.gif',
    isDirectory: false,
    size: 10240,
  }],
}, {
  name: 'System',
  isDirectory: true,
  category: 'Important',
  items: [{
    name: 'Employees.txt',
    isDirectory: false,
    category: 'Important',
    size: 3072,
  }, {
    name: 'PasswordList.txt',
    isDirectory: false,
    category: 'Important',
    size: 5120,
  }],
}, {
  name: 'Description.rtf',
  isDirectory: false,
  size: 1024,
}, {
  name: 'Description.txt',
  isDirectory: false,
  size: 2048,
}];
const fileExtensions = {
  'Text Document': '.txt',
  'RTF Document': '.rtf',
  Spreadsheet: '.xls',
};
const categories = ['Work', 'Important', 'Home', 'None'];
export function getItemInfo(name: string) {
  const extension = fileExtensions[name];
  const category = extension ?? categories.find((cat) => cat === name);
  return {
    extension,
    category,
  };
}
    
    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,
    category: 'Work',
    items: [
      {
        name: 'Projects',
        isDirectory: true,
        category: 'Work',
        items: [
          {
            name: 'About.rtf',
            isDirectory: false,
            size: 1024,
          },
          {
            name: 'Passwords.rtf',
            isDirectory: false,
            category: 'Important',
            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,
    category: 'Home',
    items: [
      {
        name: 'logo.png',
        isDirectory: false,
        size: 20480,
      },
      {
        name: 'banner.gif',
        isDirectory: false,
        size: 10240,
      },
    ],
  },
  {
    name: 'System',
    isDirectory: true,
    category: 'Important',
    items: [
      {
        name: 'Employees.txt',
        isDirectory: false,
        category: 'Important',
        size: 3072,
      },
      {
        name: 'PasswordList.txt',
        isDirectory: false,
        category: 'Important',
        size: 5120,
      },
    ],
  },
  {
    name: 'Description.rtf',
    isDirectory: false,
    size: 1024,
  },
  {
    name: 'Description.txt',
    isDirectory: false,
    size: 2048,
  },
];
const fileExtensions = {
  'Text Document': '.txt',
  'RTF Document': '.rtf',
  Spreadsheet: '.xls',
};
const categories = ['Work', 'Important', 'Home', 'None'];
export function getItemInfo(name) {
  const extension = fileExtensions[name];
  const category = extension ?? categories.find((cat) => cat === name);
  return {
    extension,
    category,
  };
}
    
    <!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" />
    <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>