React TreeView - Customize Node Appearance

For minor customization of nodes, you can define specific fields in node data objects. For example, the following code adds an icon to each node.

jQuery
JavaScript
var hierarchicalData = [{
    id: '1',
    text: 'Fruits',
    icon: '/pics/fruits.ico',
    items: [
        { id: '1_1', text: 'Apples', icon: '/pics/fruits/apple.ico' },
        { id: '1_2', text: 'Oranges', icon: '/pics/fruits/orange.ico' }
    ]
}, {
    id: '2',
    text: 'Vegetables',
    icon: '/pics/vegetables.ico',
    items: [
        { id: '2_1', text: 'Cucumbers', icon: '/pics/vegetables/cucumber.ico' },
        { id: '2_2', text: 'Tomatoes', icon: '/pics/vegetables/tomato.ico' }
    ]
}]

$(function() {
    $("#treeViewContainer").dxTreeView({
        dataSource: hierarchicalData
    });
});
Angular
HTML
TypeScript
<dx-tree-view
    [dataSource]="hierarchicalData" >
</dx-tree-view>
import { DxTreeViewModule } from "devextreme-angular";
// ...
export class AppComponent {
    hierarchicalData = [{
        id: '1',
        text: 'Fruits',
        icon: '/pics/fruits.ico',
        items: [
            { id: '1_1', text: 'Apples', icon: '/pics/fruits/apple.ico' },
            { id: '1_2', text: 'Oranges', icon: '/pics/fruits/orange.ico' }
        ]
    }, {
        id: '2',
        text: 'Vegetables',
        icon: '/pics/vegetables.ico',
        items: [
            { id: '2_1', text: 'Cucumbers', icon: '/pics/vegetables/cucumber.ico' },
            { id: '2_2', text: 'Tomatoes', icon: '/pics/vegetables/tomato.ico' }
        ]
    }];
}
@NgModule({
    imports: [
        // ...
        DxTreeViewModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxTreeView
        :items="hierarchicalData" 
    />
</template>
<script>
import 'devextreme/dist/css/dx.light.css';

import { DxTreeView } from 'devextreme-vue/tree-view';

const hierarchicalData = [{
    id: '1',
    text: 'Fruits',
    icon: '/pics/fruits.ico',
    items: [
        { id: '1_1', text: 'Apples', icon: '/pics/fruits/apple.ico' },
        { id: '1_2', text: 'Oranges', icon: '/pics/fruits/orange.ico' }
    ]
}, {
    id: '2',
    text: 'Vegetables',
    icon: '/pics/vegetables.ico',
    items: [
        { id: '2_1', text: 'Cucumbers', icon: '/pics/vegetables/cucumber.ico' },
        { id: '2_2', text: 'Tomatoes', icon: '/pics/vegetables/tomato.ico' }
    ]
}];

export default {
    components: {
        DxTreeView
    },
    data() {
        return {
            hierarchicalData
        };
    },
};
</script>
React
App.js
import React from 'react';

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

import TreeView from 'devextreme-react/tree-view';

const hierarchicalData = [{
    id: '1',
    text: 'Fruits',
    icon: '/pics/fruits.ico',
    items: [
        { id: '1_1', text: 'Apples', icon: '/pics/fruits/apple.ico' },
        { id: '1_2', text: 'Oranges', icon: '/pics/fruits/orange.ico' }
    ]
}, {
    id: '2',
    text: 'Vegetables',
    icon: '/pics/vegetables.ico',
    items: [
        { id: '2_1', text: 'Cucumbers', icon: '/pics/vegetables/cucumber.ico' },
        { id: '2_2', text: 'Tomatoes', icon: '/pics/vegetables/tomato.ico' }
    ]
}];

class App extends React.Component {
    render() {
        return (
            <TreeView
                items={hierarchicalData} />
        );
    }
}

export default App;

If you need a more flexible solution, define an itemTemplate. In Angular and Vue, you can declare it in the markup. In React, you can use a rendering function (shown in the code below) or component:

Angular
HTML
TypeScript
<dx-tree-view
    [dataSource]="hierarchicalData"
    itemTemplate="itemTemplate">
    <div *dxTemplate="let itemObj of 'itemTemplate'">
        <i>{{itemObj.text}}</i>
    </div>
</dx-tree-view>
import { DxTreeViewModule } from "devextreme-angular";
// ...
export class AppComponent {
    hierarchicalData = [{
        id: '1',
        text: 'Fruits',
        items: [
            { id: '1_1', text: 'Apples' },
            { id: '1_2', text: 'Oranges' }
        ]
    }, {
        id: '2',
        text: 'Vegetables',
        items: [
            { id: '2_1', text: 'Cucumbers' },
            { id: '2_2', text: 'Tomatoes' }
        ]
    }];
}
@NgModule({
    imports: [
        // ...
        DxTreeViewModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxTreeView
        :items="hierarchicalData">
        <template #item="item">
            <i>{{ item.data.text }}</i>
        </template>           
    </DxTreeView>    
</template>
<script>
import 'devextreme/dist/css/dx.light.css';

import { DxTreeView } from 'devextreme-vue/tree-view';

const hierarchicalData = [{
    id: '1',
    text: 'Fruits',
    items: [
        { id: '1_1', text: 'Apples' },
        { id: '1_2', text: 'Oranges' }
    ]
}, {
    id: '2',
    text: 'Vegetables',
    items: [
        { id: '2_1', text: 'Cucumbers' },
        { id: '2_2', text: 'Tomatoes' }
    ]
}];

export default {
    components: {
        DxTreeView
    },
    data() {
        return {
            hierarchicalData
        };
    },
};
</script>
React
App.js
import React from 'react';

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

import TreeView from 'devextreme-react/tree-view';

const hierarchicalData = [{
    id: '1',
    text: 'Fruits',
    items: [
        { id: '1_1', text: 'Apples' },
        { id: '1_2', text: 'Oranges' }
    ]
}, {
    id: '2',
    text: 'Vegetables',
    items: [
        { id: '2_1', text: 'Cucumbers' },
        { id: '2_2', text: 'Tomatoes' }
    ]
}];

class App extends React.Component {
    render() {
        return (
            <TreeView
                itemRender={this.renderTreeViewItem}
                items={hierarchicalData} />
        );
    }

    renderTreeViewItem(item) {
        return (
            <i>{item.text}</i>
        );
    }
}

export default App;

If you use jQuery, use DOM manipulation methods to combine the HTML markup for nodes. To apply this markup, use the itemTemplate callback function as shown in the following code:

JavaScript
$(function() {
    $("#treeViewContainer").dxTreeView({
        dataSource: treeViewData,
        itemTemplate: function (itemData, itemIndex, itemElement) {
            itemElement.append("<i>" + itemData.text + "</i>");
        }
    });
});

You can also customize individual nodes. In Angular, Vue, and React, declare them using the dxItem component. When using jQuery, you can declare the nodes as scripts and reference them in the template property or assign a customization function straight to this property.

Angular
HTML
TypeScript
<dx-tree-view>
    <dxi-item>
        <i>Apples</i>
    </dxi-item>
    <dxi-item>
        <p>Oranges</p>
    </dxi-item>
</dx-tree-view>
import { DxTreeViewModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
}
@NgModule({
    imports: [
        // ...
        DxTreeViewModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxTreeView>
        <DxItem>
            <template #default>
                <i>Apples</i>
            </template>
        </DxItem>
        <DxItem>
            <template #default>
                <p>Oranges</p>
            </template>
        </DxItem>
    </DxTreeView>
</template>
<script>
import 'devextreme/dist/css/dx.light.css';

import { DxTreeView, DxItem } from 'devextreme-vue/tree-view';

export default {
    components: {
        DxTreeView,
        DxItem
    }
};
</script>
React
App.js
import React from 'react';

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

import TreeView, { Item } from 'devextreme-react/tree-view';

class App extends React.Component {
    render() {
        return (
            <TreeView>
                <Item>
                    <i>Apples</i>
                </Item>
                <Item>
                    <p>Oranges</p>
                </Item>
            </TreeView>
        );
    }
}

export default App;
jQuery
HTML
JavaScript
<div id="treeViewContainer"></div>
<script id="individualItemTemplate" type="text/html">
    <p>Oranges</p>
</script>
var treeViewData = [{
    id: '1',
    text: 'Fruits',
    items: [{
        template: function() {
            return "<i>Apples</i>";
        }
    }, {
        template: $("#individualItemTemplate")
    }
    ]
},
// ...
];

In addition, you can use a 3rd-party template engine to customize UI component appearance. For more information, see the 3rd-Party Template Engines article.

See Also