Free Trial Buy
    Your search did not match any results.
    Tree List

    Load Data on Demand

    This example demonstrates how to load data on demand every time a user expands a TreeList node. For this purpose, filtering is delegated to the server, and IDs of expanded nodes are sent to the server with every request for data.

    See more Hide details
    Prev Demo Next Demo

    jQuery

    Angular

    Vue

    React

    AngularJS

    ASP.NET Core

    ASP.NET MVC

    Copy to CodeSandBox
    Apply
    Reset
    import React from 'react'; import { TreeList, RemoteOperations, Column } from 'devextreme-react/tree-list'; import 'whatwg-fetch'; const dataSource = { load: function(loadOptions) { let parentIdsParam = loadOptions.parentIds; return fetch(`https://js.devexpress.com/Demos/Mvc/api/treeListData?parentIds=${parentIdsParam}`) .then(response => response.json()) .catch(() => { throw 'Data Loading Error'; }); } }; class App extends React.Component { render() { return ( <TreeList id="treelist" dataSource={dataSource} showBorders={true} keyExpr="id" parentIdExpr="parentId" hasItemsExpr="hasItems" rootValue="" > <RemoteOperations filtering={true} /> <Column dataField="name" /> <Column width={100} customizeText={this.customizeText} dataField="size" /> <Column width={150} dataField="createdDate" dataType="date" /> <Column width={150} dataField="modifiedDate" dataType="date" /> </TreeList> ); } customizeText(e) { if (e.value !== null) { return `${Math.ceil(e.value / 1024) } KB`; } } } export default App;
    import React from 'react'; import ReactDOM from 'react-dom'; import App from './App.js'; ReactDOM.render( <App />, document.getElementById('app') );
    <!DOCTYPE html> <html> <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=1.0" /> <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/19.2.4/css/dx.common.css" /> <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/19.2.4/css/dx.light.css" /> <link rel="stylesheet" type ="text/css" href="styles.css" /> <script src="https://unpkg.com/core-js@2.4.1/client/shim.min.js"></script> <script src="https://unpkg.com/systemjs@0.21.3/dist/system.js"></script> <script type="text/javascript" src="config.js"></script> <script type="text/javascript"> System.import('./index.js'); </script> </head> <body class="dx-viewport"> <div class="demo-container"> <div id="app"></div> </div> </body> </html>
    #treelist { max-height: 440px; }
    System.config({ transpiler: 'plugin-babel', paths: { 'npm:': 'https://unpkg.com/' }, defaultExtension: 'js', map: { 'react': 'npm:react@16/umd/react.development.js', 'react-dom': 'npm:react-dom@16/umd/react-dom.development.js', 'prop-types': 'npm:prop-types/prop-types.js', 'devextreme': 'npm:devextreme@19.2', 'devextreme-react': 'npm:devextreme-react@19.2', 'jszip': 'npm:jszip@3.1.3/dist/jszip.min.js', 'quill': 'npm:quill@1.3.7/dist/quill.js', 'devexpress-diagram': 'npm:devexpress-diagram', 'devexpress-gantt': 'npm:devexpress-gantt', 'whatwg-fetch': 'npm:whatwg-fetch@2.0.4/fetch.js', // SystemJS plugins 'plugin-babel': 'npm:systemjs-plugin-babel@0/plugin-babel.js', 'systemjs-babel-build': 'npm:systemjs-plugin-babel@0/systemjs-babel-browser.js' }, packages: { 'devextreme': { defaultExtension: 'js' }, 'devextreme-react': { main: 'index.js' } }, babelOptions: { sourceMaps: false, stage0: true, react: true } });