JavaScript/jQuery Chart - annotations

Annotations are images and text blocks that provide additional information on the visualized data. The image below demonstrates their appearance:

To configure annotations, assign an array of objects to the annotations[] option. Each object should have the type field set to "text" or "image". Depending on the type, specify the annotation's text or image option:

$(function() {
    $("chartContainer").dxChart({
        annotations: [{
            type: "text",
            text: "Annotation text"
        }, {
            type: "image",
            image: "http://image/url/myimage.png"
        }]
    });
});

<dx-chart ... >
    <dxi-annotation
        type="text"
        text="Annotation text">
    </dxi-annotation>
    <dxi-annotation
        type="image"
        image="http://image/url/myimage.png">
    </dxi-annotation>
</dx-chart>

import { Component } from '@angular/core';
@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.css']
})
export class AppComponent {
    // ...
}

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AppComponent } from './app.component';

import { DxChartModule } from 'devextreme-angular';

@NgModule({
    declarations: [
        AppComponent
    ],
    imports: [
        BrowserModule,
        DxChartModule
    ],
    providers: [ ],
    bootstrap: [AppComponent]
})
export class AppModule { }

<template>
    <DxChart ... >
        <DxAnnotation
            type="text"
            text="Annotation text"
        />
        <DxAnnotation
            type="image"
            image="http://image/url/myimage.png"
        />
    </DxChart>
</template>

<script>
import 'devextreme/dist/css/dx.common.css';
import 'devextreme/dist/css/dx.light.css';

import DxChart, {
    DxAnnotation
} from 'devextreme-vue/chart';

export default {
    components: {
        DxChart,
        DxAnnotation
    },
    data() {
        // ...
    }
}
</script>

import React from 'react';

import 'devextreme/dist/css/dx.common.css';
import 'devextreme/dist/css/dx.light.css';

import Chart, {
    Annotation
} from 'devextreme-react/chart';

class App extends React.Component {
    render() {
        return (
            <Chart ... >
                <Annotation
                    type="text"
                    text="Annotation text"
                />
                <Annotation
                    type="image"
                    image="http://image/url/myimage.png"
                />
            </Chart>
        );
    }
}

export default App;

Annotations can be unattached or anchored to a chart element. The following list shows how to position them. Chart coordinates (argument, value, axis, series) specify the element that the annotation's arrow points to; pixel coordinates (x and y) specify the position of the annotation's center.

• Unanchored annotation

  annotations: [{
      x: 100,
      y: 200
  }]

• Annotation anchored to a chart coordinate

  annotations: [{
      argument: new Date(2019, 1, 16),
      value: 15,
      axis: "Value axis 2" // in a chart with multiple value axes
  }]

• Annotation anchored to a series point

  annotations: [{
      argument: new Date(2019, 1, 16),
      series: "Series 1"
  }]

• Annotation displayed on an axis

  annotations: [{ 
      // An annotation on the argument axis 
      argument: new Date(2019, 1, 16)
  }, { 
      // An annotation on the value axis 
      value: 15,  
      axis: "Value axis 2" // in a chart with multiple value axes
  }]

• Mixed anchoring (pixel and chart coordinates used simultaneously)

  annotations: [{
      argument: new Date(2019, 1, 16),
      y: 200
  }]

When a user long-presses an annotation or hovers the mouse pointer over it, the Chart displays a tooltip.

Objects in the annotations[] array configure individual annotations. To specify options common for all annotations, use the commonAnnotationSettings object. Individual settings take precedence over common settings.

View Demo

See Also

• customizeAnnotation

See Also

• offsetX | offsetY

See Also

• value
• series
• x | y

This option supports the following colors:

• Hexadecimal colors
• RGB colors
• RGBA colors
• Predefined/cross-browser color names
• Predefined SVG colors

Set this option to a function that returns an object with the following fields:

• color
  Specifies the color that fills the tooltip.

• text
  Specifies the tooltip's text.

• html
  Specifies the HTML markup the tooltip displays.

  NOTE

  If you are going to use external resources (for example, images) in the markup, specify the size of the area they occupy.

• fontColor
  Colors the tooltip's text.

• borderColor
  Colors the tooltip's border.

See Also

• tooltipEnabled

To display an image, assign its URL to the url option. Use the height and width options to resize the image if needed. Otherwise, you can assign the URL directly to the image option.

View Demo

The number assigned to this option specifies the shift in pixels. A negative number shifts the annotation to the left and a positive number shifts it to the right.

See Also

• allowDragging

The number assigned to this option specifies the shift in pixels. A negative number shifts the annotation up and a positive number shifts it down.

See Also

• allowDragging

This option accepts a value from 0 to 1: 0 makes the annotation transparent; 1 makes it opaque.

Use this option when the annotation is positioned relative to an argument.

For example, the following chart displays two series and an annotation. The annotation is positioned relative to the argument B but not anchored to any of the two series points that correspond to this argument:

dataSource: [
    { arg: "A", val1: 5, val2: 5.5 },
    { arg: "B", val1: 3, val2: 6.5 },
    { arg: "C", val1: 3.5, val2: 4.5 }
],
series: [
    { valueField: "val1", name: "Series 1" },
    { valueField: "val2", name: "Series 2" }
],
annotations: [{
    type: "text",
    text: "Text annotation",
    argument: "B"
}]

To anchor the annotation to one of these series points, specify the annotation's series. For instance, the following code anchors the annotation to the point of Series 1:

annotations: [{
    type: "text",
    text: "Text annotation",
    argument: "B",
    series: "Series 1"
}]

See Also

• x | y
• value

See Also

• description

Use the VizTextOverflow enum to specify this option when the widget is used as an ASP.NET MVC 5 Control or a DevExtreme-Based ASP.NET Core Control. This enum accepts the following values: Ellipsis, Hide, and None.

A tooltip is a miniature rectangle that appears when a user long-presses an annotation or hovers the mouse pointer over it.

The tooltip displays the contents of the description field or the text or markup returned from the customizeTooltip function. If the description is empty, and customizeTooltip returns nothing, the tooltip does not appear.

Tooltips for annotations and series points have the same appearance specified in the tooltip object. However, you can use the annotation's customizeTooltip function to give the annotation tooltip an individual look.

View Demo

See Also

• argument
• x | y

The following modes are available:

• "normal"
  Text breaks only at allowed breakpoints (for example, a space between two words).

• "breakWord"
  Words can be broken if there are no available breakpoints in the line.

• "none"
  Word wrap is disabled.

If the text overflows the container even after word wrap, the widget applies the textOverflow option.

Use the VizWordWrap enum to specify this option when the widget is used as an ASP.NET MVC 5 Control or a DevExtreme-Based ASP.NET Core Control. This enum accepts the following values: Normal, BreakWord, and None.

See Also

• argument | value

See Also

• argument | value