Getting started in EJ2 TypeScript Linear gauge control

3 Nov 202314 minutes to read

This section briefly explains how to create Linear Gauge component and configure its available functionalities in TypeScript using the Essential JS 2 quickstart seed repository.

This application is integrated with the webpack.config.js configuration and uses the latest version of the webpack-cli. It requires node v14.15.0 or higher. For more information about webpack and its features, refer to the webpack documentation.

Dependencies

Following is the list of minimum dependencies required to use the Linear Gauge.

|-- @syncfusion/ej2-lineargauge
    |-- @syncfusion/ej2-base
    |-- @syncfusion/ej2-pdf-export
    |-- @syncfusion/ej2-svg-base

Set up development environment

Open the command prompt from the required directory, and run the following command to clone the Syncfusion JavaScript (Essential JS 2) quickstart project from GitHub.

git clone https://github.com/SyncfusionExamples/ej2-quickstart-webpack- ej2-quickstart

After cloning the application in the ej2-quickstart folder, run the following command line to navigate to the ej2-quickstart folder.

cd ej2-quickstart

Add Syncfusion JavaScript packages

Syncfusion JavaScript (Essential JS 2) packages are available on the npmjs.com public registry. You can install all Syncfusion JavaScript (Essential JS 2) controls in a single @syncfusion/ej2 package or individual packages for each control.

The quickstart application is preconfigured with the dependent @syncfusion/ej2 package in the ~/package.json file. Use the following command to install the dependent npm packages from the command prompt.

npm install

Adding Linear Gauge component to the Project

The Essential JS2 Linear Gauge component can be added to the application. To get started, add the Linear Gauge component to the app.ts and index.html files using the following code.

Add an HTML div element to act as the Linear Gauge element in the index.html file using the following code.

index.html
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Linear gauge</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" />
</head>

<body>
    <!-- container which is going to render the linear gauge -->
    <div id='container'>
    </div>
</body>

</html>

Import the LinearGauge component in the app.ts file to initialize the Linear Gauge and append the Linear Gauge instance to the #container.

app.ts
import { LinearGauge } from '@syncfusion/ej2-lineargauge';

// initialize linear gauge component
let gauge: LinearGauge = new LinearGauge();

// render initialized linear gauge
gauge.appendTo('#container');

Run the application

The quickstart project is configured to compile and run the application in the browser. Use the following command to run the application.

npm start

The below example shows a basic Linear Gauge component.

index.ts
index.html
import { LinearGauge } from '@syncfusion/ej2-lineargauge';

let gauge: LinearGauge = new LinearGauge();
gauge.appendTo('#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Animation</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="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-popups/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'>
        <div id='element'></div>
    </div>
</body>

</html>

Module Injection

Linear Gauge component is segregated into individual feature-wise modules. In order to use a particular feature, inject its corresponding feature module using LinearGauge.Inject() method. Please find the feature module name and description as follows.

Annotation - Inject this module to use the annotation features.
GaugeTooltip - Inject this module to use the tooltip features.

Now import the above mentioned modules from the Linear Gauge package and inject it into the LinearGauge component using LinearGauge.Inject method.

app.ts
import { GaugeTooltip, Annotations } from '@syncfusion/ej2-lineargauge';
LinearGauge.Inject(Annotations, GaugeTooltip);

Adding the Linear Gauge Title

The title can be added to the Linear Gauge component using the title property in the Linear Gauge.

index.ts
index.html
import { LinearGauge } from '@syncfusion/ej2-lineargauge';
let gauge: LinearGauge = new LinearGauge({
    // Title for linear gauge
    title: 'linear gauge'
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Animation</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="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-popups/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'>
        <div id='element'></div>
    </div>
</body>

</html>

Axis Range

The range of the axis can be set using the minimum and maximum properties in the Linear Gauge.

index.ts
index.html
import { LinearGauge } from '@syncfusion/ej2-lineargauge';
let gauge: LinearGauge = new LinearGauge({
    axes: [{
        minimum: 0,
        maximum: 200
    }]
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Animation</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="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-popups/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'>
        <div id='element'></div>
    </div>
</body>

</html>

To denote the axis values with temperature units, add the °C as suffix to each label. This can be achieved by setting the {value}°C to the format property in the labelStyle object of the axis. Here, {value} acts as a placeholder for each axis label.

To change the pointer value from the default value of the gauge, set the value property in pointers object of the axis.

index.ts
index.html
import { LinearGauge } from '@syncfusion/ej2-lineargauge';
let gauge: LinearGauge = new LinearGauge({
    axes: [{
        minimum: 0,
        maximum: 200,
        pointers: [{
            value: 140
        }],
        labelStyle: {
            format: '{value}°C'
        },
        ranges: [{
            start: 0,
            end: 80,
            startWidth:15,
            endWidth:15
        }, {
            start: 80,
            end: 120,
            startWidth:15,
            endWidth:15
        }, {
            start: 120,
            end: 140,
            startWidth:15,
            endWidth:15
        }, {
            start: 140,
            end: 200,
            startWidth:15,
            endWidth:15
        }]
    }]
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Animation</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="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-popups/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'>
        <div id='element'></div>
    </div>
</body>

</html>

Setting the value of the pointer

The pointer value is changed in the below sample using the value property in pointers object of the axis.

index.ts
index.html
import { LinearGauge } from '@syncfusion/ej2-lineargauge';
let gauge: LinearGauge = new LinearGauge({
    axes:[{
        pointers:[{
            value: 40,
            color: 'green'
        }]
    }]
}, '#element');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>EJ2 Animation</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="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-popups/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'>
        <div id='element'></div>
    </div>
</body>

</html>