Data Labels in Vue Chart component

22 Jul 2021 / 9 minutes to read

Data label can be added to a chart series by enabling the visible option in the dataLabel. By default, the labels will arrange smartly without overlapping.

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis'>
            <e-series-collection>
            <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'></e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData: [
              { x: 'Jan', y: -7.1 }, { x: 'Feb', y: -3.7 },
              { x: 'Mar', y: 2 }, { x: 'Apr', y: 6.3 },
              { x: 'May', y: 13.3 }, { x: 'Jun', y: 18.0 },
              { x: 'Jul', y: 19.8 }, { x: 'Aug', y: 18.1 },
              { x: 'Sep', y: 13.1 }, { x: 'Oct', y: 4.1 },
              { x: 'Nov', y: -3.8 }, { x: 'Dec', y: -6.8 }
              ],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker: {
                    //Data label for chart series
                    dataLabel: { visible: true }
                },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  }
};
</script>
<style>
 #container {
   height: 350px;
 }
</style>

Note: To use datalabel feature, we need to inject DataLabel into the provide.

Position

Using position property, you can place the label either on Top, Middle,Bottom or Outer (outer is applicable for column and bar type series).

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis'>
            <e-series-collection>
                <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'> </e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData: [
              { x: 'Jan', y: -7.1 }, { x: 'Feb', y: -3.7 },
              { x: 'Mar', y: 2 }, { x: 'Apr', y: 6.3 },
              { x: 'May', y: 13.3 }, { x: 'Jun', y: 18.0 },
              { x: 'Jul', y: 19.8 }, { x: 'Aug', y: 18.1 },
              { x: 'Sep', y: 13.1 }, { x: 'Oct', y: 4.1 },
              { x: 'Nov', y: -3.8 }, { x: 'Dec', y: -6.8 }
              ],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker: {
                  dataLabel: { visible: true, position: 'Middle' }
                },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  }
};
</script>
<style>
#container {
   height: 350px;
 }
</style>

Note: The position Outer is applicable for column and bar type series.

Datalabel template

Label content can be formatted by using the template option. Inside the template, you can add the placeholder text ${point.x} and ${point.y} to display corresponding data points x & y value. Using template property, you can set data label template in chart.

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis'>
            <e-series-collection>
                <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'> </e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";
    let contentVue = Vue.component("contentTemplate", {
  template: `<div><div>{{data.point.x}}</div><div>{{data.point.y}}</div></div>`,
  data() {
    return {
      data: {}
    };
  }
});
let contentTemplate = function() {
  return { template: contentVue };
};

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData: [
              { x: 'Jan', y: -7.1 }, { x: 'Feb', y: -3.7 },
              { x: 'Mar', y: 2 }, { x: 'Apr', y: 6.3 },
              { x: 'May', y: 13.3 }, { x: 'Jun', y: 18.0 },
              { x: 'Jul', y: 19.8 }, { x: 'Aug', y: 18.1 },
              { x: 'Sep', y: 13.1 }, { x: 'Oct', y: 4.1 },
              { x: 'Nov', y: -3.8 }, { x: 'Dec', y: -6.8 }
              ],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker: { dataLabel: { visible: true, position: 'Middle',
                  template: contentTemplate } },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  }
};
</script>
<style>
 #container {
   height: 350px;
 }
</style>

Text Mapping

Text from the data source can be mapped using name property.

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis'>
            <e-series-collection>
                <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'> </e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData:[{ x: 'Jan', y: 12, text: 'January : 12°C' }, { x: 'Feb', y: 8, text: 'February : 8°C' },
                  { x: 'Mar', y: 11, text: 'March : 11°C' }, { x: 'Apr', y: 6, text: 'April : 6°C' }],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker: { dataLabel: { visible: true, name: 'text'} },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  }
};
</script>
<style>
 #container {
   height: 350px;
 }
</style>

Margin

margin for data label can be applied to using left, right, bottom and top properties.

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis'>
            <e-series-collection>
                <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'> </e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData: [
              { x: 'Jan', y: -7.1 }, { x: 'Feb', y: -3.7 },
              { x: 'Mar', y: 2 }, { x: 'Apr', y: 6.3 },
              { x: 'May', y: 13.3 }, { x: 'Jun', y: 18.0 },
              { x: 'Jul', y: 19.8 }, { x: 'Aug', y: 18.1 },
              { x: 'Sep', y: 13.1 }, { x: 'Oct', y: 4.1 },
              { x: 'Nov', y: -3.8 }, { x: 'Dec', y: -6.8 }
              ],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker: { dataLabel: { visible: true,border:{width: 1, color : 'red'},
                        margin:{
                            left:5,
                            right:5,
                            top:5,
                            bottom:5
                        } }
        },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  }
};
</script>
<style>
 #container {
   height: 350px;
 }
</style>

DataLabel Rotation

Using angle property, you can rotate the data label by its given angle.

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis'>
            <e-series-collection>
                <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'> </e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData: [
              { x: 'Jan', y: -7.1 }, { x: 'Feb', y: -3.7 },
              { x: 'Mar', y: 2 }, { x: 'Apr', y: 6.3 },
              { x: 'May', y: 13.3 }, { x: 'Jun', y: 18.0 },
              { x: 'Jul', y: 19.8 }, { x: 'Aug', y: 18.1 },
              { x: 'Sep', y: 13.1 }, { x: 'Oct', y: 4.1 },
              { x: 'Nov', y: -3.8 }, { x: 'Dec', y: -6.8 }
              ],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker: { dataLabel: { visible: true,border:{width: 1, color : 'red'},
                        margin:{
                            left:5,
                            right:5,
                            top:5,
                            bottom:5
                        }, angle: 45, enableRotation: true }
        },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  }
};
</script>
<style>
 #container {
   height: 350px;
 }
</style>

Customization

stroke and border of data label can be customized using fill and border properties. Rounded corners can be customized using rx and ry properties.

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis'>
            <e-series-collection>
                <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'> </e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData: [
              { x: 'Jan', y: -7.1 }, { x: 'Feb', y: -3.7 },
              { x: 'Mar', y: 2 }, { x: 'Apr', y: 6.3 },
              { x: 'May', y: 13.3 }, { x: 'Jun', y: 18.0 },
              { x: 'Jul', y: 19.8 }, { x: 'Aug', y: 18.1 },
              { x: 'Sep', y: 13.1 }, { x: 'Oct', y: 4.1 },
              { x: 'Nov', y: -3.8 }, { x: 'Dec', y: -6.8 }
              ],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker:{ dataLabel: { visible: true,
                        border:{width: 2, color : 'red'},
                        rx:10, ry: 10
                    }
        },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  }
};
</script>
<style>
#container {
   height: 350px;
 }
</style>

Note: rx and ry properties requires border values not to be null.

Customizing Specific Point

You can also customize the specific marker and label using pointRender and textRender event. pointRender event allows you to change the shape, color and border for a point, whereas the textRender event allows you to change the text for the point.

Source

Preview

app.vue

<template>
    <div id="app">
         <ejs-chart id= "container" :title='title' :primaryXAxis='primaryXAxis' :pointRender='pointRender' :textRender='textRender'>
            <e-series-collection>
                <e-series :dataSource='seriesData' type='Column' xName='x' yName='y' name='Warmest' :marker='marker'> </e-series>
            </e-series-collection>
        </ejs-chart>
    </div>
</template>
<script>
import Vue from "vue";
import { ChartPlugin, ColumnSeries, Category, DataLabel } from "@syncfusion/ej2-vue-charts";

Vue.use(ChartPlugin);

export default {
  data() {
    return {
      seriesData: [
              { x: 'Jan', y: -7.1 }, { x: 'Feb', y: -3.7 },
              { x: 'Mar', y: 2 }, { x: 'Apr', y: 6.3 },
              { x: 'May', y: 13.3 }, { x: 'Jun', y: 18.0 },
              { x: 'Jul', y: 19.8 }, { x: 'Aug', y: 18.1 },
              { x: 'Sep', y: 13.1 }, { x: 'Oct', y: 4.1 },
              { x: 'Nov', y: -3.8 }, { x: 'Dec', y: -6.8 }
              ],
        primaryXAxis: {
           valueType: 'Category'
        },
        marker:{ dataLabel: { visible: true } },
      title: "Alaska Weather Statistics - 2016"
    };
  },
  provide: {
    chart: [ColumnSeries, Category, DataLabel]
  },
  methods: {
      pointRender: function(args) {
       if (args.point.index === 6) {
                args.fill = 'red'
        }
  },
   textRender: function(args) {
      if (args.point.index === 6) {
                args.text = 'Maximum Temperature';
                args.color = 'red';
            }
  }
  }
};
</script>
<style>
 #container {
   height: 350px;
 }
</style>

Contents

Position
Datalabel template
Text Mapping
Margin
DataLabel Rotation
Customization
Customizing Specific Point

Contents

Position
Datalabel template
Text Mapping
Margin
DataLabel Rotation
Customization
Customizing Specific Point