Angular List - Customize Group Headers

You can define a groupTemplate to customize group headers. In Angular and Vue, declare the template in the markup. In React, use a rendering function (shown in the code below) or component. Without a groupTemplate, group headers display the text of the key field in bold font.

Angular
HTML
TypeScript
<dx-list
    [dataSource]="listDataSource"
    [grouped]="true"
    groupTemplate="group"
    itemTemplate="item">
    <div *dxTemplate="let itemObj of 'item'">
        <p style="margin:0px">{{itemObj.name}} | {{itemObj.count}}</p>
    </div>
    <div *dxTemplate="let groupObj of 'group'">
        <p>{{groupObj.key}} | {{groupObj.overallCount}}</p>
    </div>
</dx-list>
import { DxListModule } from "devextreme-angular";
import DataSource from "devextreme/data/data_source";
// ...
export class AppComponent {
    fruitsVegetables = [{
        key: "Fruits",
        items: [
            { name: "Apples", count: 10 },
            { name: "Oranges", count: 12 },
            { name: "Lemons", count: 15 }
        ]
    }, {
        key: "Vegetables",
        items: [
            { name: "Potatoes", count: 5 },
            { name: "Tomatoes", count: 9 },
            { name: "Turnips", count: 8 }
        ]
    }];
    listDataSource = new DataSource({
        store: fruitsVegetables,
        map: function(groupedItem) {
            let overallCount = 0;
            groupedItem.items.forEach(function(item) {
                overallCount += item.count;
            })
            return Object.assign(groupedItem, { overallCount: overallCount });
        }
    });
}
@NgModule({
    imports: [
        // ...
        DxListModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxList
        :data-source="listDataSource"
        :grouped="true"
        item-template="list-item"
        group-template="group-header">
        <template #list-item="{ data }">
            <p style="margin:0px">{{ data.name }} | {{ data.count }}</p>
        </template>
        <template #group-header="{ data }">
            <p>{{ data.key }} | {{ data.overallCount }}</p>
        </template>
    </DxList>
</template>

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

import DxList from 'devextreme-vue/list';
import DataSource from 'devextreme/data/data_source';

const fruitsVegetables = [{
    key: "Fruits",
    items: [
        { name: "Apples", count: 10 },
        { name: "Oranges", count: 12 },
        { name: "Lemons", count: 15 }
    ]
}, {
    key: "Vegetables",
    items: [
        { name: "Potatoes", count: 5 },
        { name: "Tomatoes", count: 9 },
        { name: "Turnips", count: 8 }
    ]
}];

const listDataSource = new DataSource({
    store: fruitsVegetables,
    map: function(groupedItem) {
        let overallCount = 0;
        groupedItem.items.forEach(function(item) {
            overallCount += item.count;
        });
        return Object.assign(groupedItem, { overallCount: overallCount });
    }
});

export default {
    components: {
        DxList
    },
    data() {
        return {
            listDataSource
        }
    }
}
</script>
React
App.js
import React from 'react';
import 'devextreme/dist/css/dx.light.css';

import List from 'devextreme-react/list';
import DataSource from 'devextreme/data/data_source';

const fruitsVegetables = [{
    key: "Fruits",
    items: [
        { name: "Apples", count: 10 },
        { name: "Oranges", count: 12 },
        { name: "Lemons", count: 15 }
    ]
}, {
    key: "Vegetables",
    items: [
        { name: "Potatoes", count: 5 },
        { name: "Tomatoes", count: 9 },
        { name: "Turnips", count: 8 }
    ]
}];

const listDataSource = new DataSource({
    store: fruitsVegetables,
    map: function(groupedItem) {
        let overallCount = 0;
        groupedItem.items.forEach(function(item) {
            overallCount += item.count;
        });
        return Object.assign(groupedItem, { overallCount: overallCount });
    }
});

const ListItem = (data) => {
    return (
        <p style={{ margin: '0px' }}>{ data.name } | { data.count }</p>
    );
};

const ListGroupHeader = (data) => {
    return (
        <p>{ data.key } | { data.overallCount }</p>
    );
};

export default function App() {
    return (
        <List
            dataSource={listDataSource}
            grouped={true}
            itemRender={ListItem}
            groupRender={ListGroupHeader}
        />
    );
}

If you use jQuery alone, use DOM manipulation methods to combine the HTML markup for group headers. To apply this markup, use the groupTemplate callback function as shown in the following code.

JavaScript
const fruitsVegetables = [{
    key: "Fruits",
    items: [
        { name: "Apples", count: 10 },
        { name: "Oranges", count: 12 },
        { name: "Lemons", count: 15 }
    ]
}, {
    key: "Vegetables",
    items: [
        { name: "Potatoes", count: 5 },
        { name: "Tomatoes", count: 9 },
        { name: "Turnips", count: 8 }
    ]
}];

$(function() {
    $("#listContainer").dxList({
        dataSource: new DevExpress.data.DataSource({
            store: fruitsVegetables,
            map: function(groupedItem) {
                let overallCount = 0;
                groupedItem.items.forEach(function(item) {
                    overallCount += item.count;
                });
                return $.extend(groupedItem, { overallCount: overallCount })
            }
        }),
        grouped: true,
        groupTemplate: function(groupData, _, groupElement) {
            groupElement.append(
                $("<p>").text(groupData.key + " | " + groupData.overallCount)
            )
        },
        itemTemplate: function(data, _, element) {
            element.append(
                $("<p>").text(data.name + " | " + data.count).css("margin", 0)
            )
        }
    });
});

View Demo

In addition, you can use a 3rd-party template engine to perform the needed customizations. For more information, see the 3rd-Party Template Engines article.

See Also