Annotations in JavaScript (ES5) Chart control

30 Mar 2023 / 3 minutes to read

Annotations are used to mark the specific area of interest in the chart area with texts, shapes or images.

You can add annotations to the chart by using the annotations option. By using the content option of annotation object, you can specify either the id of the element or directly specify the element in the content that needs to be displayed in the chart area.

Source

Preview

index.js

index.html

var chartData = [
      { country: "USA", gold: 50, silver: 70, bronze: 45 },
      { country: "China", gold: 40, silver: 60, bronze: 55 },
      { country: "Japan", gold: 70, silver: 60, bronze: 50 },
      { country: "Australia", gold: 60, silver: 56, bronze: 40 },
      { country: "France", gold: 50, silver: 45, bronze: 35 },
      { country: "Germany", gold: 40, silver: 30, bronze: 22 },
      { country: "Italy", gold: 40, silver: 35, bronze: 37 },
      { country: "Sweden", gold: 30, silver: 25, bronze: 27 }
];
var chart = new ej.charts.Chart({
    primaryXAxis: {
        valueType: 'Category',
        // label placement as on ticks
        labelPlacement: 'OnTicks',
        title: 'Countries'
    },
    primaryYAxis: {
        minimum: 0, maximum: 80,
        interval: 20, title: 'Medals'
    },
    annotations:[{
        content: '70 Gold Medals',
        region: 'Series',
        coordinateUnits: 'Point',
        x: 'Japan',
        y: 75
    }],
    series:[{
        dataSource: chartData,
        xName: 'country', yName: 'gold',
        name: 'Gold', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'silver',
        name: 'Silver', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'bronze',
        name: 'Bronze', type: 'Column'
    }],
    title: 'Olympic Medals'
}, '#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">
    
    
<script src="https://cdn.syncfusion.com/ej2/21.1.35/dist/ej2.min.js" type="text/javascript"></script>
</head>

<body>
    
    <div id="container">
        <div id="element"></div>
		   <div id="element1"></div>
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Note: To use annotations feature, we need to inject ChartAnnotation using Chart.Inject(ChartAnnotation) method.

Region

Annotations can be placed either with respect to Series or Chart. by default, it will placed with respect to Chart.

Source

Preview

index.js

index.html

var chartData = [
      { country: "USA", gold: 50, silver: 70, bronze: 45 },
      { country: "China", gold: 40, silver: 60, bronze: 55 },
      { country: "Japan", gold: 70, silver: 60, bronze: 50 },
      { country: "Australia", gold: 60, silver: 56, bronze: 40 },
      { country: "France", gold: 50, silver: 45, bronze: 35 },
      { country: "Germany", gold: 40, silver: 30, bronze: 22 },
      { country: "Italy", gold: 40, silver: 35, bronze: 37 },
      { country: "Sweden", gold: 30, silver: 25, bronze: 27 }
];
var chart = new ej.charts.Chart({
    primaryXAxis: {
        valueType: 'Category',
        // label placement as on ticks
        labelPlacement: 'OnTicks',
        title: 'Countries'
    },
    primaryYAxis: {
        minimum: 0, maximum: 80,
        interval: 20, title: 'Medals'
    },
    annotations:[{
        content: '70 Gold Medals',
        region: 'Series',
        coordinateUnits: 'Point',
        x: 'Japan',
        y: 75
    }],
    series:[{
        dataSource: chartData,
        xName: 'country', yName: 'gold',
        name: 'Gold', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'silver',
        name: 'Silver', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'bronze',
        name: 'Bronze', type: 'Column'
    }],
    title: 'Olympic Medals'
}, '#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">
    
    
<script src="https://cdn.syncfusion.com/ej2/21.1.35/dist/ej2.min.js" type="text/javascript"></script>
</head>

<body>
    
    <div id="container">
        <div id="element"></div>
		   <div id="element1"></div>
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Co-ordinate Units

Specified the coordinates units of the annotation either Pixel or Point.

Source

Preview

index.js

index.html

var chartData = [
      { country: "USA", gold: 50, silver: 70, bronze: 45 },
      { country: "China", gold: 40, silver: 60, bronze: 55 },
      { country: "Japan", gold: 70, silver: 60, bronze: 50 },
      { country: "Australia", gold: 60, silver: 56, bronze: 40 },
      { country: "France", gold: 50, silver: 45, bronze: 35 },
      { country: "Germany", gold: 40, silver: 30, bronze: 22 },
      { country: "Italy", gold: 40, silver: 35, bronze: 37 },
      { country: "Sweden", gold: 30, silver: 25, bronze: 27 }
];
var chart = new ej.charts.Chart({
    primaryXAxis: {
        valueType: 'Category',
        // label placement as on ticks
        labelPlacement: 'OnTicks',
        title: 'Countries'
    },
    primaryYAxis: {
        minimum: 0, maximum: 80,
        interval: 20, title: 'Medals'
    },
    annotations:[{
        content: '70 Gold Medals',
        region: 'Series',
        coordinateUnits: 'Point',
        x: 'Japan',
        y: 75
    }],
    series:[{
        dataSource: chartData,
        xName: 'country', yName: 'gold',
        name: 'Gold', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'silver',
        name: 'Silver', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'bronze',
        name: 'Bronze', type: 'Column'
    }],
    title: 'Olympic Medals'
}, '#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">
    
    
<script src="https://cdn.syncfusion.com/ej2/21.1.35/dist/ej2.min.js" type="text/javascript"></script>
</head>

<body>
    
    <div id="container">
        <div id="element"></div>
		   <div id="element1"></div>
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Alignment

Annotation provides verticalAlignment and horizontalAlignment. The verticalAlignment can be customized via Top, Bottom or Middle and the horizontalAlignment can be customized via Near, Far or Center.

Source

Preview

index.js

index.html

var chartData = [
      { country: "USA", gold: 50, silver: 70, bronze: 45 },
      { country: "China", gold: 40, silver: 60, bronze: 55 },
      { country: "Japan", gold: 70, silver: 60, bronze: 50 },
      { country: "Australia", gold: 60, silver: 56, bronze: 40 },
      { country: "France", gold: 50, silver: 45, bronze: 35 },
      { country: "Germany", gold: 40, silver: 30, bronze: 22 },
      { country: "Italy", gold: 40, silver: 35, bronze: 37 },
      { country: "Sweden", gold: 30, silver: 25, bronze: 27 }
];
var chart = new ej.charts.Chart({
    primaryXAxis: {
        valueType: 'Category',
        // label placement as on ticks
        labelPlacement: 'OnTicks',
        title: 'Countries'
    },
    primaryYAxis: {
        minimum: 0, maximum: 80,
        interval: 20, title: 'Medals'
    },
    annotations:[{
        content: '70 Gold Medals',
        region: 'Series',
        coordinateUnits: 'Point',
        x: 'Japan',
        y: 75
    }],
    series:[{
        dataSource: chartData,
        xName: 'country', yName: 'gold',
        name: 'Gold', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'silver',
        name: 'Silver', type: 'Column'
    }, {
        dataSource: chartData,
        xName: 'country', yName: 'bronze',
        name: 'Bronze', type: 'Column'
    }],
    title: 'Olympic Medals'
}, '#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">
    
    
<script src="https://cdn.syncfusion.com/ej2/21.1.35/dist/ej2.min.js" type="text/javascript"></script>
</head>

<body>
    
    <div id="container">
        <div id="element"></div>
		   <div id="element1"></div>
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Adding y-axis sub title through on annotation

By setting text div in the content option of annotation object you can add sub title to chart y-axis. Specified the coordinate value as pixel and customize x and y location of the text.

Source

Preview

index.js

index.html

var chart = new ej.charts.Chart({
        primaryXAxis: {
            valueType: 'Category',
        },
        primaryYAxis: {
            title: '(m2/min)'
        },
        annotations: [{
                content: '<div id="text" style="transform: rotate(-90deg);">Speed Rate</div>',
                x: 6,
                y: 180,
                coordinateUnits: 'Pixel',
                Region: 'Chart'
            }],
        series: [{
                dataSource: datasource.columnData,
                xName: 'country', yName: 'gold',
                type: 'Column'
            }],
    }, '#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">
    
    
<script src="https://cdn.syncfusion.com/ej2/21.1.35/dist/ej2.min.js" type="text/javascript"></script>
</head>

<body>
    
    <div id="container">
        <div id="element"></div>
		   <div id="element1"></div>
    </div>


<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

Annotations in JavaScript (ES5) Chart control

Region

Co-ordinate Units

Alignment

Adding y-axis sub title through on annotation

See Also