Grouping in EJ2 TypeScript Multi select control
2 May 202313 minutes to read
The MultiSelect supports wrapping nested elements into a group based on different categories. The category of each list item can be mapped through the groupBy field in the data table. The group header is displayed both as inline and fixed headers. The fixed group header content is updated dynamically on scrolling the popup list with its category value.
In the following sample, vegetables are grouped according on its category using groupBy field.
import { MultiSelect } from '@syncfusion/ej2-dropdowns';
//define the data with category
let vegetableData: { [key: string]: Object }[] = [
{ vegetable: 'Cabbage', category: 'Leafy and Salad', id: 'item1' },
{ vegetable: 'Spinach', category: 'Leafy and Salad', id: 'item2' },
{ vegetable: 'Wheat grass', category: 'Leafy and Salad', id: 'item3' },
{ vegetable: 'Yarrow', category: 'Leafy and Salad', id: 'item4' },
{ vegetable: 'Pumpkins', category: 'Leafy and Salad', id: 'item5' },
{ vegetable: 'Chickpea', category: 'Beans', id: 'item6' },
{ vegetable: 'Green bean', category: 'Beans', id: 'item7' },
{ vegetable: 'Horse gram', category: 'Beans', id: 'item8' },
{ vegetable: 'Garlic', category: 'Bulb and Stem', id: 'item9' },
{ vegetable: 'Nopal', category: 'Bulb and Stem', id: 'item10' },
{ vegetable: 'Onion', category: 'Bulb and Stem', id: 'item11' }
];
//initiate the MultiSelect
let vegetables: MultiSelect = new MultiSelect({
//set the grouped data to dataSource property
dataSource: vegetableData,
// map the groupBy field with category column
fields: { groupBy: 'category', text: 'vegetable', value: 'id' },
// set the placeholder to the MultiSelect input
placeholder: "Select vegetables",
// Set the popup list height
popupHeight: '200px'
});
//render the MultiSelect component
vegetables.appendTo('#select');<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2 MultiSelect</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="styles.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-dropdowns/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-buttons/styles/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>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container' style="margin:0 auto; width:250px;">
<br>
<!--element which is going to render the MultiSelect-->
<input type="text" tabindex="1" id='select' />
</div>
</body>
</html>HTML select
The MultiSelect also supports grouping of list items under specific groups by initiating the <select> element using optgroup. The nested items are wrapped based on the <optgroup> tag that is presents in the <select> element
<select id="selectElement">
<optgroup label="Beans">
<option value="1">Chickpea</option>
<option value="2">Green bean</option>
<option value="3">Horse gram</option>
</optgroup>
<optgroup label="Leafy and Salad">
<option value="4">Spinach</option>
<option value="5" selected="selected">Cabbage</option>
<option value="6">Wheat grass</option>
</optgroup>
</select>
import { MultiSelect } from '@syncfusion/ej2-dropdowns';
// initialize MultiSelect component
let msObject: MultiSelect = new MultiSelect({
placeholder:"Select vegetables"
});
// render initialized MultiSelect
msObject.appendTo('#selectElement');<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2 MultiSelect</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="styles.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-dropdowns/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-buttons/styles/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>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container' style="margin:0 auto; width:250px;">
<select id="selectElement">
<optgroup label="Beans">
<option value="1">Chickpea</option>
<option value="2">Green bean</option>
<option value="3">Horse gram</option>
</optgroup>
<optgroup label="Leafy and Salad">
<option value="4" selected="selected">Cabbage</option>
<option value="5">Spinach</option>
<option value="6">Wheat grass</option>
</optgroup>
</select>
</div>
</body>
</html>Customization
The grouping header is also provided with customization option. This allows custom designing using the groupTemplate property for both inline and fixed headers.
Grouping with CheckBox
Previously, there is no checkbox for group headers. Now, this feature allow to render checkbox in group header to select the group items in single selection. You can enable this feature by setting enableGroupCheckBox property value as true and mode property as CheckBox.
Inject the CheckBoxSelection module in the MultiSelect to use the checkbox.
import { MultiSelect, CheckBoxSelection } from '@syncfusion/ej2-dropdowns';
MultiSelect.Inject(CheckBoxSelection);
//define the array of complex data
let sportsData: { [key: string]: Object }[] = [
{ vegetable: 'Cabbage', category: 'Leafy and Salad', id: 'item1' },
{ vegetable: 'Spinach', category: 'Leafy and Salad', id: 'item2' },
{ vegetable: 'Wheat grass', category: 'Leafy and Salad', id: 'item3' },
{ vegetable: 'Yarrow', category: 'Leafy and Salad', id: 'item4' },
{ vegetable: 'Pumpkins', category: 'Leafy and Salad', id: 'item5' },
{ vegetable: 'Chickpea', category: 'Beans', id: 'item6' },
{ vegetable: 'Green bean', category: 'Beans', id: 'item7' },
{ vegetable: 'Horse gram', category: 'Beans', id: 'item8' },
{ vegetable: 'Garlic', category: 'Bulb and Stem', id: 'item9' },
{ vegetable: 'Nopal', category: 'Bulb and Stem', id: 'item10' },
{ vegetable: 'Onion', category: 'Bulb and Stem', id: 'item11' }
];
//initiate the MultiSelect
let msObject: MultiSelect = new MultiSelect({
// bind the sports Data to datasource property
dataSource: sportsData,
// maps the appropriate column to fields property
fields: { groupBy: 'category', text: 'vegetable', value: 'id' },
//set the placeholder to MultiSelect input
placeholder:"Select vegetables",
// set the type of mode for checkbox to visualized the checkbox added in li element.
mode: 'CheckBox',
// set true for enable the selectAll support.
showSelectAll: true,
// set value for allowFiltering as true
allowFiltering: true,
// set placeholder to filterbar
filterBarPlaceholder: "Search Vegetables",
// set true for enableGroupCheckBox property
enableGroupCheckBox: true
});
//render the component
msObject.appendTo('#select');<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2 MultiSelect</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="styles.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-dropdowns/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/28.1.33/ej2-buttons/styles/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>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container' style="margin:0 auto; width:250px;">
<br>
<!--element which is going to render the MultiSelect-->
<input type="text" tabindex="1" id='select' />
</div>
</body>
</html>