DevExtreme Angular - Customize Item Appearance

For a minor customization of Lookup items, you can use the default item template. This template defines the appearance of an item depending on whether specific fields are present or absent from the item's data object. For example, the following code generates three items: the first is not customized, the second is disabled and the third is hidden.

jQuery
JavaScript
$(function() {
    $("#lookupContainer").dxLookup({
        valueExpr: 'text',
        displayExpr: 'text',
        dataSource: [
            { text: "HD Video Player" },
            { text: "SuperHD Video Player", disabled: true },
            { text: "SuperPlasma 50", visible: false }
        ]
    });
});
Angular
TypeScript
HTML
import { DxLookupModule } from "devextreme-angular";
// ...
export class AppComponent {
    lookupDataSource = [
        { text: "HD Video Player" },
        { text: "SuperHD Video Player", disabled: true },
        { text: "SuperPlasma 50", visible: false }
    ];
}
@NgModule({
    imports: [
        // ...
        DxLookupModule
    ],
    // ...
})
<dx-lookup
    [dataSource]="lookupDataSource"
    valueExpr="text"
    displayExpr="text">
</dx-lookup>

Using the default item template is the easiest way to customize an item, but it lacks flexibility. Instead, you can define a custom template for widget items. For Angular, AngularJS and Knockout apps, DevExtreme provides a markup component called dxTemplate. The following code shows how you can use dxTemplate to define a template for the Lookup items.

Angular
HTML
TypeScript
<dx-lookup
    [dataSource]="lookupDataSource"
    valueExpr="id"
    itemTemplate="lookupItem">
    <div *dxTemplate="let item of 'lookupItem'; let i = index">
        <img src="{{item.imgSrc}}"/>
        <div 
            style="display:inline-block" 
            [style.font-style]="i % 2 == 0 ? 'italic' : 'normal'">
            {{item.name}}
        </div>
    </div>
</dx-lookup>
import { DxLookupModule } from "devextreme-angular";
// ...
export class AppComponent {
    lookupDataSource = [{
        id: 1,
        name: "HD Video Player",
        imgSrc: "images/products/1-small.png"
    }, {
        id: 2,
        name: "UltraHD Player",
        imgSrc: "images/products/2-small.png"
    },
    // ...
    ];
}
@NgModule({
    imports: [
        // ...
        DxLookupModule
    ],
    // ...
})
AngularJS
HTML
JavaScript
<div ng-controller="DemoController">
    <div dx-lookup="{
        dataSource: lookupData,
        valueExpr: 'id',
        itemTemplate: 'item'
    }" dx-item-alias="product">
        <div data-options="dxTemplate: { name: 'item' }">
            <img ng-src="{{product.imgSrc}}"/>
            <div 
                style="display:inline-block; 
                font-style:{{$index % 2 == 0 ? 'italic' : 'normal'}}">
                {{product.name}}
            </div>
        </div>
    </div>
</div>
angular.module('DemoApp', ['dx'])
    .controller('DemoController', function ($scope) {
        $scope.lookupData = [{
            id: 1,
            name: "HD Video Player",
            imgSrc: "images/products/1-small.png"
        }, {
            id: 2,
            name: "UltraHD Player",
            imgSrc: "images/products/2-small.png"
        },
        // ...
        ];
    });
NOTE
The dx-item-alias directive specifies the variable that is used to access the item object.
Knockout
HTML
JavaScript
<div data-bind="dxLookup: {
    dataSource: lookupData,
    valueExpr: 'id',
    itemTemplate: 'item'
}">
    <div data-options="dxTemplate: { name: 'item' }">
        <img data-bind="attr: { src: imgSrc }"/>
        <div style="display:inline-block" data-bind="{
            style: { 'font-style': $index % 2 == 0 ? 'italic' : 'normal' },
            text: name
        }"></div>
    </div>
</div>
var viewModel = {
    lookupData: [{
        id: 1,
        name: "HD Video Player",
        imgSrc: "images/products/1-small.png"
    }, {
        id: 2,
        name: "UltraHD Player",
        imgSrc: "images/products/2-small.png"
    },
    // ...
    ]
};

ko.applyBindings(viewModel);

If you use jQuery alone, combine the HTML markup for items manually with jQuery DOM manipulation methods. To apply this markup, use the itemTemplate callback function as shown in the following code.

JavaScript
var lookupData = [{
    id: 1,
    name: "HD Video Player",
    imgSrc: "images/products/1-small.png"
}, {
    id: 2,
    name: "UltraHD Player",
    imgSrc: "images/products/2-small.png"
},
// ...
];

$(function() {
    $("#lookupContainer").dxLookup({
        dataSource: lookupData,
        valueExpr: 'id',
        displayExpr: 'name',
        itemTemplate: function (itemData, itemIndex, itemElement) {
            return $("<div />").append(
                        $("<img />").attr("src", itemData.imgSrc),
                        $("<p />").text(itemData.name)
                                .css("display", "inline-block")
                                .css("font-style", (itemIndex % 2 == 0) ? "italic" : "normal")
                    );
        }
    });
});

You can also customize an individual Lookup item. For this purpose, declare a template for this item as a script and pass its id to the template field.

HTML
JavaScript
<script id="individualTemplate" type="text/html">
    <!-- ... -->
</script>
var lookupData = [
    { text: "SuperHD Player"},
    { text: "HD Video Player", template: $("#individualTemplate") },
    // ...
];

Using similar techniques, you can customize the input field of the Lookup. The template for it should be assigned to the fieldTemplate option.

jQuery
JavaScript
$(function() {
    $("#lookupContainer").dxLookup({
        dataSource: lookupData,
        valueExpr: 'id',
        displayExpr: 'name',
        fieldTemplate: function(itemData, itemElement) {
            return $("<div />").append(
                $("<img />").attr("src", itemData.imgSrc)
            );
        }
    });
});
Angular
HTML
TypeScript
<dx-lookup
    [dataSource]="lookupDataSource"
    valueExpr="id"
    displayExpr="name"
    fieldTemplate="inputField">
    <div *dxTemplate="let item of 'inputField'">
        <img src="{{item.imgSrc}}" />
    </div>
</dx-lookup>
import { DxLookupModule } from "devextreme-angular";
// ...
export class AppComponent {
    lookupDataSource = [{
        id: 1,
        name: "HD Video Player",
        imgSrc: "images/products/1-small.png"
    }, {
        id: 2,
        name: "UltraHD Player",
        imgSrc: "images/products/2-small.png"
    },
    // ...
    ];
}
@NgModule({
    imports: [
        // ...
        DxLookupModule
    ],
    // ...
})
AngularJS
HTML
<div ng-controller="DemoController">
    <div dx-lookup="{
        dataSource: lookupData,
        valueExpr: 'id',
        displayExpr: 'name',
        fieldTemplate: 'inputField'
    }" dx-item-alias="product">
        <div data-options="dxTemplate: { name: 'inputField' }">
            <img ng-src="{{ product.imgSrc }}" />
        </div>
    </div>
</div>
Knockout
HTML
<div data-bind="dxLookup: {
    dataSource: lookupData,
    valueExpr: 'id',
    displayExpr: 'name',
    fieldTemplate: 'inputField'
}">
    <div data-options="dxTemplate: { name: 'inputField' }">
        <img data-bind="attr: { src: imgSrc }" />
    </div>
</div>

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