To keep single pane open always in React Accordion component

30 Jan 20239 minutes to read

By default, all Accordion panels are collapsible. You can customize the Accordion to keep one panel as expanded state always. This is applicable for Single expand mode.

import * as React from "react";
import { useState, useRef } from "react";
import * as ReactDOM from "react-dom";
import { AccordionComponent, AccordionItemsDirective, AccordionItemDirective } from '@syncfusion/ej2-react-navigations';
const ReactApp = () => {
  const acrdnInstance = useRef(null);
  const [clickEle, setClickEle] = useState(null);
  const expanding = (e) => {
    if (acrdnInstance.current) {
      let expandCount = acrdnInstance.current.element.querySelectorAll('.e-selected').length;
      let ele = acrdnInstance.current.element.querySelectorAll('.e-selected')[0];
      if (ele) {
        ele = ele.firstChild;
      }
      if (expandCount === 1 && ele === clickEle) {
        e.cancel = true;
      }
    }
  }
  const clicked = (e) => {
    setClickEle((e.originalEvent.target).closest('.e-acrdn-header'));
  }

  const aspContent = () => {
    return (<div>
      Microsoft ASP.NET is a set of technologies in the Microsoft .NET Framework for building Web applications and XML Web services.
    </div>);
  }

  const mvcContent = () => {
    return (<div>
      The Model-View-Controller (MVC) architectural pattern separates an application into three main components: the model, the view, and the controller.
    </div>);
  }

  const jsContent = () => {
    return (<div>
      JavaScript (JS) is an interpreted computer programming language.It was originally implemented as part of web browsers so that client-side scripts could interact with the user, control the browser, communicate asynchronously, and alter the document content that was displayed.
    </div>);
  }

  return (
    <AccordionComponent ref={acrdnInstance} expandMode='Single' clicked={clicked} expanding={expanding}>
      <AccordionItemsDirective>
        <AccordionItemDirective expanded={true} header='ASP.NET' content={aspContent} />
        <AccordionItemDirective header='ASP.NET MVC' content={mvcContent} />
        <AccordionItemDirective header='JavaScript' content={jsContent} />
      </AccordionItemsDirective>
    </AccordionComponent>
  );
}

const root = ReactDOM.createRoot(document.getElementById('element'));
root.render(<ReactApp />);
import * as React from "react";
import { useState, useRef } from "react";
import * as ReactDOM from "react-dom";
import { AccordionComponent, AccordionItemsDirective, AccordionItemDirective } from '@syncfusion/ej2-react-navigations';
import { ExpandEventArgs, AccordionClickArgs } from '@syncfusion/ej2-navigations';
const ReactApp = () => {
  const acrdnInstance = useRef<AccordionComponent>(null);
  const [clickEle, setClickEle] = useState(null);
  const expanding = (e: ExpandEventArgs) => {
    if (acrdnInstance.current) {
      let expandCount: number = acrdnInstance.current.element.querySelectorAll('.e-selected').length;
      let ele: HTMLElement = acrdnInstance.current.element.querySelectorAll('.e-selected')[0] as HTMLElement;
      if (ele) {
        ele = ele.firstChild as HTMLElement;
      }
      if (expandCount === 1 && ele === clickEle) {
        e.cancel = true;
      }
    }
  }
  const clicked = (e: AccordionClickArgs) => {
    setClickEle((e.originalEvent.target as Element).closest('.e-acrdn-header'));
  }
  const aspContent = () => {
    return (<div>
      Microsoft ASP.NET is a set of technologies in the Microsoft .NET Framework for building Web applications and XML Web services.
    </div>);
  }

  const mvcContent = () => {
    return (<div>
      The Model-View-Controller (MVC) architectural pattern separates an application into three main components: the model, the view, and the controller.
    </div>);
  }

  const jsContent = () => {
    return (<div>
      JavaScript (JS) is an interpreted computer programming language.It was originally implemented as part of web browsers so that client-side scripts could interact with the user, control the browser, communicate asynchronously, and alter the document content that was displayed.
    </div>);
  }

  return (
    <AccordionComponent ref={acrdnInstance} expandMode='Single' clicked={clicked} expanding={expanding}>
      <AccordionItemsDirective>
        <AccordionItemDirective expanded={true} header='ASP.NET' content={aspContent} />
        <AccordionItemDirective header='ASP.NET MVC' content={mvcContent} />
        <AccordionItemDirective header='JavaScript' content={jsContent} />
      </AccordionItemsDirective>
    </AccordionComponent>
  );
}

const root = ReactDOM.createRoot(document.getElementById('element'));
root.render(<ReactApp />);
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 React Accordion Sample</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 for React Components" />
    <meta name="author" content="Syncfusion" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/material.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
    <style>
        #loader {
            color: #008cff;
            height: 40px;
            left: 45%;
            position: absolute;
            top: 45%;
            width: 30%;
        }
    </style>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='element'>
        <div id='loader'>Loading....</div></div>
</body>
</html>