Angular DropDownBox Properties

An object defining configuration properties for the DropDownBox UI component.

acceptCustomValue

Specifies whether the UI component allows a user to enter a custom value.

Type:

Boolean

Default Value: false

accessKey

Specifies the shortcut key that sets focus on the UI component.

Type:

String

Default Value: undefined

The value of this property will be passed to the accesskey attribute of the HTML element that underlies the UI component.

activeStateEnabled

Specifies whether the UI component changes its visual state as a result of user interaction.

Type:

Boolean

Default Value: true

The UI component switches to the active state when users press down the primary mouse button. When this property is set to true, the CSS rules for the active state apply. You can change these rules to customize the component.

Use this property when you display the component on a platform whose guidelines include the active state change for UI components.

buttons[]

Allows you to add custom buttons to the input text field.

Selector: dxi-button
Type:

Array<DropDownPredefinedButton | TextEditorButton>

Default Value: undefined

Built-in buttons should also be declared in this array. You can find an example in the following demo:

View Demo

contentTemplate

Specifies a custom template for the drop-down content.

Type:

template

Template Data:
Name Type Description
component

DropDownBox

The UI component's instance.

value any

The currently selected value.

Default Name: 'content'

dataSource

Binds the UI component to data.

Default Value: null

The DropDownBox works with collections of objects or string, number, or boolean values. The component does not support hierarchical data sources.

Depending on your data source, bind the DropDownBox to data as follows. In each case, also specify the valueExpr and displayExpr properties if the data source provides objects.

  • Data Array
    Assign the array to the dataSource option.

  • Read-Only Data in JSON Format
    Set the dataSource property to the URL of a JSON file or service that returns JSON data.

  • OData
    Implement an ODataStore.

  • Web API, PHP, MongoDB
    Use one of the following extensions to enable the server to process data according to the protocol DevExtreme UI components use:

    Then, use the createStore method to configure access to the server on the client as shown below. This method is part of DevExtreme.AspNet.Data.

    jQuery
    JavaScript
    $(function() {
        let serviceUrl = "https://url/to/my/service";
        $("#dropDownBoxContainer").dxDropDownBox({
            // ...
            dataSource: DevExpress.data.AspNet.createStore({
                key: "ID",
                loadUrl: serviceUrl + "/GetAction",
                insertUrl: serviceUrl + "/InsertAction",
                updateUrl: serviceUrl + "/UpdateAction",
                deleteUrl: serviceUrl + "/DeleteAction"
            })
        })
    });
    Angular
    app.component.ts
    app.component.html
    app.module.ts
    import { Component } from '@angular/core';
    import CustomStore from 'devextreme/data/custom_store';
    import { createStore } from 'devextreme-aspnet-data-nojquery';
    
    @Component({
        selector: 'app-root',
        templateUrl: './app.component.html',
        styleUrls: ['./app.component.css']
    })
    export class AppComponent {
        store: CustomStore;
        constructor() {
            let serviceUrl = "https://url/to/my/service";
            this.store = createStore({
                key: "ID",
                loadUrl: serviceUrl + "/GetAction",
                insertUrl: serviceUrl + "/InsertAction",
                updateUrl: serviceUrl + "/UpdateAction",
                deleteUrl: serviceUrl + "/DeleteAction"
            })
        }
    }
    <dx-drop-down-box ...
        [dataSource]="store">
    </dx-drop-down-box>
    import { BrowserModule } from '@angular/platform-browser';
    import { NgModule } from '@angular/core';
    import { AppComponent } from './app.component';
    
    import { DxDropDownBoxModule } from 'devextreme-angular';
    
    @NgModule({
        declarations: [
            AppComponent
        ],
        imports: [
            BrowserModule,
            DxDropDownBoxModule
        ],
        providers: [],
        bootstrap: [AppComponent]
    })
    export class AppModule { }
    Vue
    App.vue
    <template> 
        <DxDropDownBox ...
            :data-source="store" />
    </template>
    
    <script>
    import 'devextreme/dist/css/dx.light.css';
    
    import CustomStore from 'devextreme/data/custom_store';
    import { createStore } from 'devextreme-aspnet-data-nojquery';
    import { DxDropDownBox } from 'devextreme-vue/drop-down-box';
    
    export default {
        components: {
            DxDropDownBox
        },
        data() {
            const serviceUrl = "https://url/to/my/service";
            const store = createStore({
                key: "ID",
                loadUrl: serviceUrl + "/GetAction",
                insertUrl: serviceUrl + "/InsertAction",
                updateUrl: serviceUrl + "/UpdateAction",
                deleteUrl: serviceUrl + "/DeleteAction"
            });
            return {
                store
            }
        }
    }
    </script>
    React
    App.js
    import React from 'react';
    import 'devextreme/dist/css/dx.light.css';
    
    import CustomStore from 'devextreme/data/custom_store';
    import { createStore } from 'devextreme-aspnet-data-nojquery';
    import DropDownBox from 'devextreme-react/drop-down-box';
    
    const serviceUrl = "https://url/to/my/service";
    const store = createStore({
        key: "ID",
        loadUrl: serviceUrl + "/GetAction",
        insertUrl: serviceUrl + "/InsertAction",
        updateUrl: serviceUrl + "/UpdateAction",
        deleteUrl: serviceUrl + "/DeleteAction"
    });
    
    class App extends React.Component {
        render() {
            return (
                <DropDownBox ...
                    dataSource={store} />
            );
        }
    }
    export default App;
  • Any other data source
    Implement a CustomStore.

Regardless of the data source on the input, the DropDownBox always wraps it in the DataSource object. This object allows you to sort, filter, group, and perform other data shaping operations. To get its instance, call the getDataSource() method.

If the element embedded in the DropDownBox UI component is another DevExtreme UI component, their data sources should be interrelated. Refer to the Synchronize with the Embedded Element article for more information.

NOTE

Review the following notes about data binding:

  • Do not specify the items property if you specified the dataSource, and vice versa.

  • Data field names cannot be equal to this and should not contain the following characters: ., :, [, and ].

jQuery
  • The stores are immutable. You cannot change their configurations at runtime. Instead, create a new store or DataSource and assign it to the dataSource property as shown in the following help topic: Get and Set Properties.
Angular
  • The stores are immutable. You cannot change their configurations at runtime. Instead, create a new store or DataSource and assign it to the dataSource property as shown in the following help topic: Two-Way Property Binding.
Vue
  • The stores are immutable. You cannot change their configurations at runtime. Instead, create a new store or DataSource and assign it to the dataSource property as shown in the following help topic: Two-Way Property Binding.
React
  • The stores are immutable. You cannot change their configurations at runtime. Instead, create a new store or DataSource and assign it to the dataSource property as shown in the following help topic: Controlled Mode.

deferRendering

Specifies whether to render the drop-down field's content when it is displayed. If false, the content is rendered immediately.

Type:

Boolean

Default Value: true

Angular

If you set the deferRendering property to true, wrap the content in the Angular named template.

Vue

If you set the deferRendering property to true, wrap the content in the Vue named template.

disabled

Specifies whether the UI component responds to user interaction.

Type:

Boolean

Default Value: false

displayExpr

Specifies the data field whose values should be displayed.

Type:

String

|

Function

Function parameters:
item:

Object

The current item's data object.

Return Value:

String

The displayed value.

Default Value: undefined

Set this property to the name of a data field that provides displayed values...

displayExpr: "name"

... or to a function that returns the displayed value:

displayExpr: function(item) {
    // "item" can be null
    return item && 'ID: ' + item.id + ', Name: ' + item.name;
}

Leave this property unspecified or set it to this if the data source contains primitives.

See Also

displayValueFormatter

Customizes text before it is displayed in the input field.

Type:

Function

Function parameters:
value:

String

|

Array<any>

One or more values from the displayExpr that correspond(s) to the selected UI component values.

Return Value:

String

Text for the input field.

This function receives values from the data field set in the displayExpr property and should return a string that contains text for the input field. If the displayExpr is not set, the function receives full data objects.

The following code demonstrates how to change separators from commas to semicolons by using the displayValueFormatter function. You can try it if you copy this code to the Multiple Selection demo:

jQuery
index.js
$(function() {
    $("#dropDownBoxContainer").dxDropDownBox({
        displayValueFormatter: function(value) {
            return Array.isArray(value) ? value.join("; ") : value;
        },
        // ...
    });
});
Angular
app.component.html
app.component.ts
app.module.ts
<dx-drop-down-box ...
    [displayValueFormatter]="displayValueFormatter"
>
    <!-- ... -->
</dx-drop-down-box>
import { Component } from '@angular/core';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.css']
})
export class AppComponent {
    // ...
    displayValueFormatter(value) {
        return Array.isArray(value) ? value.join("; ") : value;
    }
}
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppComponent } from './app.component';

import { DxDropDownBoxModule } from 'devextreme-angular';

@NgModule({
declarations: [
    AppComponent
],
imports: [
    BrowserModule,
    DxDropDownBoxModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }
Vue
App.vue
<template>
    <DxDropDownBox ...
        :display-value-formatter="displayValueFormatter"
    >
        <!-- ... -->
    </DxDropDownBox>
</template>

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

import { DxDropDownBox } from 'devextreme-vue/drop-down-box';

export default {
    components: {
        DxDropDownBox
    },
    // ...
    methods: {
        displayValueFormatter: function(value) {
            return Array.isArray(value) ? value.join("; ") : value;
        }
    }    
};
</script>
React
App.js
import React from 'react';

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

import { DropDownBox } from 'devextreme-react/drop-down-box';

class App extends React.Component {
    render() {
        return (
            <DropDownBox ...
                displayValueFormatter={this.displayValueFormatter}
            />
        );
    }

    displayValueFormatter(value) {
        return Array.isArray(value) ? value.join("; ") : value;
    }
}

export default App;

dropDownButtonTemplate

Specifies a custom template for the drop-down button.

Type:

template

Template Data:
Name Type Description
icon

String

The button's icon.

text

String

The button's text.

Default Name: 'dropDownButton'

dropDownOptions

Configures the drop-down field which holds the content.

Default Value: {}

See Popup Configuration for properties that you can specify in this object.

Angular
NOTE
The nested component that configures the dropDownOptions property does not support event bindings and two-way property bindings.
Vue
NOTE
The nested component that configures the dropDownOptions property does not support event bindings and two-way property bindings.

elementAttr

Specifies the global attributes to be attached to the UI component's container element.

Selector: dxo-element-attr
Type:

Object

Default Value: {}

jQuery
$(function(){
    $("#dropDownBoxContainer").dxDropDownBox({
        // ...
        elementAttr: {
            id: "elementId",
            class: "class-name"
        }
    });
});
Angular
HTML
TypeScript
<dx-drop-down-box ...
    [elementAttr]="{ id: 'elementId', class: 'class-name' }">
</dx-drop-down-box>
import { DxDropDownBoxModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
}
@NgModule({
    imports: [
        // ...
        DxDropDownBoxModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxDropDownBox ...
        :element-attr="dropDownBoxAttributes">
    </DxDropDownBox>
</template>

<script>
import DxDropDownBox from 'devextreme-vue/drop-down-box';

export default {
    components: {
        DxDropDownBox
    },
    data() {
        return {
            dropDownBoxAttributes: {
                id: 'elementId',
                class: 'class-name'
            }
        }
    }
}
</script>
React
App.js
import React from 'react';

import DropDownBox from 'devextreme-react/drop-down-box';

class App extends React.Component {
    dropDownBoxAttributes = {
        id: 'elementId',
        class: 'class-name'
    }

    render() {
        return (
            <DropDownBox ...
                elementAttr={this.dropDownBoxAttributes}>
            </DropDownBox>
        );
    }
}
export default App;

fieldTemplate

Specifies a custom template for the text field. Must contain the TextBox UI component.

Type:

template

Template Data:

Object

Selected values.

Default Name: null

In the following code, the fieldTemplate is used to stylize the text field with a custom CSS class:

jQuery
index.js
style.css
$(function () {
    $("#dropDownBoxContainer").dxDropDownBox({
        // ...
        fieldTemplate: function (value, fieldElement) {
            const result = $("<div class='custom-item'>");
            result
                .dxTextBox({
                    value: value,
                    readOnly: true
                });
            fieldElement.append(result);
        }
    });
});
.custom-item {
    font-size: 16px;
}
Angular
app.component.html
app.component.css
<dx-drop-down-box ...
    fieldTemplate="field">
    <div *dxTemplate="let data of 'field'">
        <div class="custom-item">
            <dx-text-box
                [value]="data"
                [readOnly]="true"
            ></dx-text-box>
        </div>
    </div>
</dx-drop-down-box>
.custom-item {
    font-size: 16px;
}
Vue
App.vue
style.css
<template>
    <DxDropDownBox ...
        field-template="field">
        <template #field="{ value }">
            <div class="custom-item">
                <DxTextBox
                    :value="value"
                    :read-only="true"
                />
            </div>
        </template>
    </DxDropDownBox>
</template>

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

import DxDropDownBox from 'devextreme-vue/drop-down-box';
import DxTextBox from 'devextreme-vue/text-box';

export default {
    components: {
        DxDropDownBox,
        DxTextBox,
    },
    data() {
        // ...
    },
    methods: {
        // ...
    }
};
</script>
.custom-item {
    font-size: 16px;
}
React
App.js
style.css
import React from 'react';
import 'devextreme/dist/css/dx.light.css';

import { DropDownBox } from 'devextreme-react/drop-down-box';
import { TextBox } from 'devextreme-react/text-box';

const fieldRender = value => {
    return (
        <div class="custom-item">
            <TextBox
                defaultValue={value}
                readOnly={true}
            />
        </div>
    );
}

const App = () => <DropDownBox fieldRender={fieldRender}/>;

export default App;
.custom-item {
    font-size: 16px;
}
See Also

focusStateEnabled

Specifies whether the UI component can be focused using keyboard navigation.

Type:

Boolean

Default Value: true

height

Specifies the UI component's height.

Type:

Number

|

String

|

Function

Return Value:

Number

|

String

The UI component's height.

Default Value: undefined

This property accepts a value of one of the following types:

  • Number
    The height in pixels.

  • String
    A CSS-accepted measurement of height. For example, "55px", "20vh", "80%", "inherit".

  • Function (deprecated since v21.2)
    Refer to the W0017 warning description for information on how you can migrate to viewport units.

hint

Specifies text for a hint that appears when a user pauses on the UI component.

Type:

String

Default Value: undefined

hoverStateEnabled

Specifies whether the UI component changes its state when a user pauses on it.

Type:

Boolean

Default Value: true

inputAttr

Specifies the attributes to be passed on to the underlying HTML element.

Type: any
Default Value: {}

jQuery
$(function(){
    $("#dropDownBoxContainer").dxDropDownBox({
        // ...
        inputAttr: {
            id: "inputId"
        }
    });
});
Angular
HTML
TypeScript
<dx-drop-down-box ...
    [inputAttr]="{ id: 'inputId' }">
</dx-drop-down-box>
import { DxDropDownBoxModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
}
@NgModule({
    imports: [
        // ...
        DxDropDownBoxModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxDropDownBox
        :input-attr="inputAttr"
    />
</template>

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

import DxDropDownBox from 'devextreme-vue/drop-down-box';

export default {
    components: {
        DxDropDownBox
    },
    data() {
        return {
            inputAttr: { id: 'inputId' }
        }
    }
}
</script>
React
App.js
import 'devextreme/dist/css/dx.light.css';

import DropDownBox from 'devextreme-react/drop-down-box';

const inputAttr = { id: 'inputId' };

export default function App() {
    return (
        <DropDownBox
            inputAttr={inputAttr}
        />
    );
}
ASP.NET MVC Controls
Razor C#
Razor VB
@(Html.DevExtreme().DropDownBox()
    .InputAttr("id", "inputId")
    // ===== or =====
    .InputAttr(new {
        @id = "inputId"
    })
    // ===== or =====
    .InputAttr(new Dictionary<string, object>() {
        { "id", "inputId" }
    })
)
@(Html.DevExtreme().DropDownBox() _
    .InputAttr("id", "inputId")
    ' ===== or =====
    .InputAttr(New With {
        .id = "inputId"
    })
    ' ===== or =====
    .InputAttr(New Dictionary(Of String, Object) From {
        { "id", "inputId" }
    })
)

To improve accessibility, use this property to specify aria-label for the component.

jQuery
index.js
$(function(){
    $("#dropDownBoxContainer").dxDropDownBox({
        // ...
        inputAttr: {
            'aria-label': 'your-label',
        },
    });
});
Angular
app.component.html
<dx-drop-down-box ...
    [inputAttr]="{ 'aria-label': 'your-label' }">
</dx-drop-down-box>
Vue
App.vue
<template>
    <DxDropDownBox
        :input-attr="inputAttr"
    />
</template>

<script>
import DxDropDownBox from 'devextreme-vue/drop-down-box';

export default {
    components: {
        DxDropDownBox
    },
    data() {
        return {
            inputAttr: { 'aria-label': 'your-label' }
        }
    }
}
</script>
React
App.js
import DropDownBox from 'devextreme-react/drop-down-box';

const inputAttr = { 'aria-label': 'your-label' };

export default function App() {
    return (
        <DropDownBox
            inputAttr={inputAttr}
        />
    );
}

You do not need to specify aria-label if you use label.

isDirty

Specifies whether the component's current value differs from the initial value.

Type:

Boolean

Default Value: false

This property is a read-only flag. You can use it to check if the editor value changed.

jQuery
index.js
$(() => {
    const dropDownBox = $('#dropDownBox').dxDropDownBox({
        // ...
    }).dxDropDownBox('instance');

    $('#button').dxButton({
        // ...
        onClick () {
            if (dropDownBox.option('isDirty')) {
                DevExpress.ui.notify("Do not forget to save changes", "warning", 500);
            }
        }
    });
});
Angular
app.component.ts
app.component.html
import { Component, ViewChild } from '@angular/core';
import { DxDropDownBoxComponent, DxButtonModule } from 'devextreme-angular';
import notify from 'devextreme/ui/notify';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.css']
})
export class AppComponent {
    @ViewChild('dropDownBoxRef', { static: false }) dropDownBox: DxDropDownBoxComponent;

    onClick () {
        if (this.dropDownBox.instance.option('isDirty')) {
            notify("Do not forget to save changes", "warning", 500);
        }
    }
}
<dx-drop-down-box ... 
    #dropDownBoxRef
>
</dx-drop-down-box>
<dx-button ...
    (onClick)="onClick($event)"
>
</dx-button>
Vue
App.vue
<template>
    <DxDropDownBox ...
        :ref="dropDownBoxRef"
    >
    </DxDropDownBox>
    <DxButton ...
        @click="onClick"
    />
</template>

<script>
import 'devextreme/dist/css/dx.light.css';
import DxDropDownBox from 'devextreme-vue/drop-down-box';
import DxButton from 'devextreme-vue/button';
import notify from 'devextreme/ui/notify';

export default {
    components: {
        DxDropDownBox,
        DxButton
    },

    data() {
        return {
            dropDownBoxRef
        }
    },

    methods: {
        onClick () {
            if (this.dropDownBox.option('isDirty')) {
                notify("Do not forget to save changes", "warning", 500);
            }
        }
    },

    computed: {
        dropDownBox: function() {
            return this.$refs[dropDownBoxRef].instance;
        }
    }
}
</script>
React
App.js
import React, { useRef } from 'react';
import DropDownBox from 'devextreme-react/drop-down-box';
import Button from 'devextreme-react/button';
import 'devextreme/dist/css/dx.light.css';

const App = () => {
    const dropDownBoxRef = useRef(null);

    const onClick = () => {
        if (this.dropDownBoxRef.current.instance.option('isDirty')) {
            notify("Do not forget to save changes", "warning", 500);
        }
    };

    return (
        <DropDownBox ...
            ref={dropDownBoxRef}
        >
        </DropDownBox>
        <Button ...
            onClick={onClick}
        />
    );
};

export default App;
See Also

isValid

Specifies or indicates whether the editor's value is valid.

Type:

Boolean

Default Value: true

NOTE
When you use async rules, isValid is true if the status is "pending" or "valid".
See Also

items[]

An array of items used to synchronize the DropDownBox with an embedded UI component.

Type:

Array<any>

The DropDownBox uses other UI components to render items. Use the contentTemplate to embed a UI component such as the List or the TreeView. In this case, items are displayed in accordance with the configuration and functionality of the embedded UI component.

If you need to update UI component items, reassign the items array as shown in the following example:

JavaScript
dropDownBoxInstance.option('items', newItems);

You can use the dataSource property instead of items. It accepts the DataSource object whose underlying stores include API that allows you to update individual items without reassigning the entire item collection.

NOTE
Do not use the items property if you use dataSource (and vice versa).

label

Specifies a text string used to annotate the editor's value.

Type:

String

Default Value: ''

labelMode

Specifies the label's display mode.

Type:

LabelMode

Default Value: 'static', 'floating' (Material), 'outside' (Fluent)

This property can have one of the following values:

labelMode Description Illustration
"static" The label is displayed above the input field.
"floating" The label is used as a placeholder, but when the editor gets focus,
the label moves to the position above the input field.
"hidden" The label is hidden.
"outside" The label is outside.
NOTE

If autofill is enabled in the browser, we do not recommend that you use "floating" mode. The autofill values will overlap the label when it is displayed as a placeholder. Use "static" mode instead.

maxLength

Specifies the maximum number of characters you can enter into the textbox.

Type:

String

|

Number

Default Value: null

If the number of entered characters reaches the value assigned to this property, the UI component does not allow you to enter any more characters.

name

The value to be assigned to the name attribute of the underlying HTML element.

Type:

String

Default Value: ''

Specify this property if the UI component lies within an HTML form that will be submitted.

onChange

A function that is executed when the UI component loses focus after the text field's content was changed using the keyboard.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onClosed

A function that is executed once the drop-down editor is closed.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onCopy

A function that is executed when the UI component's input has been copied.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onCut

A function that is executed when the UI component's input has been cut.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onDisposing

A function that is executed before the UI component is disposed of.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onEnterKey

A function that is executed when the Enter key has been pressed while the UI component is focused.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

NOTE
This function is executed after the onKeyUp and onKeyDown functions.

onFocusIn

A function that is executed when the UI component gets focus.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onFocusOut

A function that is executed when the UI component loses focus.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onInitialized

A function used in JavaScript frameworks to save the UI component instance.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

Angular
app.component.html
app.component.ts
<dx-drop-down-box ...
    (onInitialized)="saveInstance($event)">
</dx-drop-down-box>
import { Component } from "@angular/core";
import DropDownBox from "devextreme/ui/data_grid";
// ...
export class AppComponent {
    dropDownBoxInstance: DropDownBox;
    saveInstance (e) {
        this.dropDownBoxInstance = e.component;
    }
}
Vue
App.vue (Options API)
App.vue (Composition API)
<template>
    <div>
        <DxDropDownBox ...
            @initialized="saveInstance">
        </DxDropDownBox>
    </div>
</template>

<script>
import DxDropDownBox from 'devextreme-vue/drop-down-box';

export default {
    components: {
        DxDropDownBox
    },
    data: function() {
        return {
            dropDownBoxInstance: null
        };
    },
    methods: {
        saveInstance: function(e) {
            this.dropDownBoxInstance = e.component;
        }
    }
};
</script>
<template>
    <div>
        <DxDropDownBox ...
            @initialized="saveInstance">
        </DxDropDownBox>
    </div>
</template>

<script setup>
import DxDropDownBox from 'devextreme-vue/drop-down-box';

let dropDownBoxInstance = null;

const saveInstance = (e) => {
    dropDownBoxInstance = e.component;
}
</script>
React
App.js
import DropDownBox from 'devextreme-react/drop-down-box';

class App extends React.Component {
    constructor(props) {
        super(props);

        this.saveInstance = this.saveInstance.bind(this);
    }

    saveInstance(e) {
        this.dropDownBoxInstance = e.component;
    }

    render() {
        return (
            <div>
                <DropDownBox onInitialized={this.saveInstance} />
            </div>
        );
    }
}
See Also
jQuery
  • Get a UI component Instance in jQuery
Angular
  • Get a UI component Instance in Angular
Vue
  • Get a UI component Instance in Vue
React
  • Get a UI component Instance in React

onInput

A function that is executed each time the UI component's input is changed while the UI component is focused.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onKeyDown

A function that is executed when a user is pressing a key on the keyboard.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onKeyUp

A function that is executed when a user releases a key on the keyboard.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onOpened

A function that is executed once the drop-down editor is opened.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onOptionChanged

A function that is executed after a UI component property is changed.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
value any

The modified property's new value.

previousValue any

The UI component's previous value.

name

String

The modified property if it belongs to the first level. Otherwise, the first-level property it is nested into.

fullName

String

The path to the modified property that includes all parent properties.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

The following example shows how to subscribe to component property changes:

jQuery
index.js
$(function() {
    $("#dropDownBoxContainer").dxDropDownBox({
        // ...
        onOptionChanged: function(e) {
            if(e.name === "changedProperty") {
                // handle the property change here
            }
        }
    });
});
Angular
app.component.html
app.component.ts
app.module.ts
<dx-drop-down-box ...
    (onOptionChanged)="handlePropertyChange($event)"> 
</dx-drop-down-box>
import { Component } from '@angular/core'; 

@Component({ 
    selector: 'app-root', 
    templateUrl: './app.component.html', 
    styleUrls: ['./app.component.css'] 
}) 

export class AppComponent { 
    // ...
    handlePropertyChange(e) {
        if(e.name === "changedProperty") { 
            // handle the property change here
        }
    }
}
import { BrowserModule } from '@angular/platform-browser'; 
import { NgModule } from '@angular/core'; 
import { AppComponent } from './app.component'; 
import { DxDropDownBoxModule } from 'devextreme-angular'; 

@NgModule({ 
    declarations: [ 
        AppComponent 
    ], 
    imports: [ 
        BrowserModule, 
        DxDropDownBoxModule 
    ], 
    providers: [ ], 
    bootstrap: [AppComponent] 
}) 

export class AppModule { }  
Vue
App.vue
<template> 
    <DxDropDownBox ...
        @option-changed="handlePropertyChange"
    />            
</template> 

<script>  
import 'devextreme/dist/css/dx.light.css'; 
import DxDropDownBox from 'devextreme-vue/drop-down-box'; 

export default { 
    components: { 
        DxDropDownBox
    }, 
    // ...
    methods: { 
        handlePropertyChange: function(e) {
            if(e.name === "changedProperty") {
                // handle the property change here
            }
        }
    } 
} 
</script> 
React
App.js
import React from 'react';  
import 'devextreme/dist/css/dx.light.css'; 

import DropDownBox from 'devextreme-react/drop-down-box'; 

const handlePropertyChange = (e) => {
    if(e.name === "changedProperty") {
        // handle the property change here
    }
}

export default function App() { 
    return ( 
        <DropDownBox ...
            onOptionChanged={handlePropertyChange}
        />        
    ); 
} 

onPaste

A function that is executed when the UI component's input has been pasted.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

onValueChanged

A function that is executed after the UI component's value is changed.

Type:

Function

Function parameters:

Information about the event.

Object structure:
Name Type Description
value

Object

The UI component's new value.

previousValue

Object

The UI component's previous value.

event

Event (jQuery or EventObject)

The event that caused the function to execute. It is an EventObject or a jQuery.Event when you use jQuery. This field is undefined if the value is changed programmatically.

element

HTMLElement | jQuery

The UI component's container. It is an HTML Element or a jQuery Element when you use jQuery.

component

DropDownBox

The UI component's instance.

Default Value: null

opened

Specifies whether or not the drop-down editor is displayed.

Type:

Boolean

Default Value: false
Raised Events: onClosed onOpened

openOnFieldClick

Specifies whether a user can open the drop-down list by clicking a text field.

Type:

Boolean

Default Value: true

placeholder

Specifies a text string displayed when the editor's value is empty.

Type:

String

Default Value: ''

See Also

readOnly

Specifies whether the editor is read-only.

Type:

Boolean

Default Value: false

When this property is set to true, the following applies:

  • The editor's value cannot be changed using the UI.
  • Built-in action buttons are invisible.
  • Custom action buttons are visible but disabled. If a button should not be disabled, set its disabled property to false:

    jQuery
    index.js
    $(function() {
        $("#dropDownBoxContainer").dxDropDownBox({
            // ...
            buttons: [{
                name: "myCustomButton",
                location: "after",
                options: {
                    onClick: function(e) {
                        // ...
                    },
                    disabled: false
                }
            }]
        });
    });
    Angular
    app.component.html
    app.component.ts
    app.module.ts
    <dx-drop-down-box ... >
        <dxi-button
            name="myCustomButton"
            location="after"
            [options]="myCustomButtonConfig">
        </dxi-button>
    </dx-drop-down-box>
    import { Component } from '@angular/core';
    
    @Component({
        selector: 'app-root',
        templateUrl: './app.component.html',
        styleUrls: ['./app.component.css']
    })
    export class AppComponent {
        myCustomButtonConfig = {
            onClick: (e) => {
                // ...
            },
            disabled: false
        };
    }
    import { BrowserModule } from '@angular/platform-browser';
    import { NgModule } from '@angular/core';
    import { AppComponent } from './app.component';
    
    import { DxDropDownBoxModule } from 'devextreme-angular';
    
    @NgModule({
        declarations: [
            AppComponent
        ],
        imports: [
            BrowserModule,
            DxDropDownBoxModule
        ],
        providers: [ ],
        bootstrap: [AppComponent]
    })
    export class AppModule { }
    Vue
    App.vue
    <template>
        <DxDropDownBox ... >
            <DxDropDownBoxButton
                name="myCustomButton"
                location="after"
                :options="myCustomButtonConfig"
            />
        </DxDropDownBox>
    </template>
    
    <script>
    import 'devextreme/dist/css/dx.light.css';
    
    import DxDropDownBox, {
        DxButton as DxDropDownBoxButton
    } from 'devextreme-vue/drop-down-box';
    
    export default {
        components: {
            DxDropDownBox,
            DxDropDownBoxButton
        },
        data() {
            return {
                myCustomButtonConfig: {
                    onClick: (e) => {
                        // ...
                    },
                    disabled: false
                }
            }
        }
    }
    </script>
    React
    App.js
    import React from 'react';
    
    import 'devextreme/dist/css/dx.light.css';
    
    import DropDownBox, {
        Button as DropDownBoxButton
    } from 'devextreme-react/drop-down-box';
    
    class App extends React.Component {
        myCustomButtonConfig = {
            onClick: (e) => {
                // ...
            },
            disabled: false
        };
        render() {
            return (
                <DropDownBox>
                    <DropDownBoxButton
                        name="myCustomButton"
                        location="after"
                        options={this.myCustomButtonConfig}
                    />
                </DropDownBox>
            );
        }
    }
    export default App;

    You can also hide a custom action button when the UI component becomes read-only. Set the button's visible property to false in the onOptionChanged function. To get the button, use the getButton(name) method:

    jQuery
    index.js
    $(function() {
        $("#dropDownBoxContainer").dxDropDownBox({
            // ...
            buttons: [{
                name: "myCustomButton",
                // ...
            }],
            onOptionChanged: function(e) {
                if(e.name == "readOnly") {
                    const myButton = e.component.getButton("myCustomButton");
                    myButton.option("visible", !e.value); // Hide the button when readOnly: true
                }
            }
        });
    });
    Angular
    app.component.html
    app.component.ts
    app.module.ts
    <dx-drop-down-box ...
        (onOptionChanged)="changeButtonState">
        <dxi-button
            name="myCustomButton"
            ...
        ></dxi-button>
    </dx-drop-down-box>
    import { Component } from '@angular/core';
    
    @Component({
        selector: 'app-root',
        templateUrl: './app.component.html',
        styleUrls: ['./app.component.css']
    })
    export class AppComponent {
        changeButtonState(e) {
            if(e.name == 'readOnly') {
                let myButton = e.component.getButton('myCustomButton');
                myButton.option('visible', !e.value); // Hide the button when readOnly: true
            }
        }
    }
    import { BrowserModule } from '@angular/platform-browser';
    import { NgModule } from '@angular/core';
    import { AppComponent } from './app.component';
    
    import { DxDropDownBoxModule } from 'devextreme-angular';
    
    @NgModule({
        declarations: [
            AppComponent
        ],
        imports: [
            BrowserModule,
            DxDropDownBoxModule
        ],
        providers: [ ],
        bootstrap: [AppComponent]
    })
    export class AppModule { }
    Vue
    App.vue
    <template>
        <DxDropDownBox ...
            @option-changed="changeButtonState">
            <DxDropDownBoxButton
                name="myCustomButton"
                ...
            />
        </DxDropDownBox>
    </template>
    
    <script>
    import 'devextreme/dist/css/dx.light.css';
    
    import DxDropDownBox, {
        DxButton as DxDropDownBoxButton
    } from 'devextreme-vue/drop-down-box';
    
    export default {
        components: {
            DxDropDownBox,
            DxDropDownBoxButton
        },
        data() {
            return {
                // ...
            }
        },
        methods: {
            changeButtonState(e) {
                if(e.name == 'readOnly') {
                    let myButton = e.component.getButton('myCustomButton');
                    myButton.option('visible', !e.value); // Hide the button when readOnly: true
                }
            }
        }
    }
    </script>
    React
    App.js
    import React from 'react';
    
    import 'devextreme/dist/css/dx.light.css';
    
    import DropDownBox, {
        Button as DropDownBoxButton
    } from 'devextreme-react/drop-down-box';
    
    class App extends React.Component {
        changeButtonState(e) {
            if(e.name == 'readOnly') {
                let myButton = e.component.getButton('myCustomButton');
                myButton.option('visible', !e.value); // Hide the button when readOnly: true
            }
        }
        render() {
            return (
                <DropDownBox ...
                    onOptionChanged={this.changeButtonState}>
                    <DropDownBoxButton
                        name="myCustomButton"
                        ...
                    />
                </DropDownBox>
            );
        }
    }
    export default App;

rtlEnabled

Switches the UI component to a right-to-left representation.

Type:

Boolean

Default Value: false

When this property is set to true, the UI component text flows from right to left, and the layout of elements is reversed. To switch the entire application/site to the right-to-left representation, assign true to the rtlEnabled field of the object passed to the DevExpress.config(config) method.

JavaScript
DevExpress.config({
    rtlEnabled: true
});

DataGrid Demo Navigation UI Demo Editors Demo

showClearButton

Specifies whether to display the Clear button in the UI component.

Type:

Boolean

Default Value: false

The Clear button calls the reset method.

showDropDownButton

Specifies whether the drop-down button is visible.

Type:

Boolean

Default Value: true

stylingMode

Specifies how the UI component's text field is styled.

Type:

EditorStyle

Default Value: 'outlined', 'filled' (Material)

The following styles are available:

Text Editor Styling Modes

You can also use the global editorStylingMode setting to specify how the text fields of all editors in your application are styled.

tabIndex

Specifies the number of the element when the Tab key is used for navigating.

Type:

Number

Default Value: 0

The value of this property will be passed to the tabindex attribute of the HTML element that underlies the UI component.

text

The read-only property that holds the text displayed by the UI component input element.

Type:

String

Read-only

validationError

Information on the broken validation rule. Contains the first item from the validationErrors array.

Type: any
Default Value: null

See Also

validationErrors

An array of the validation rules that failed.

Type:

Array<any>

Default Value: null

validationMessageMode

Specifies how the message about the validation rules that are not satisfied by this editor's value is displayed.

Default Value: 'auto'

The following property values are possible:

  • auto
    The tooltip with the message is displayed when the editor is in focus.
  • always
    The tooltip with the message is not hidden when the editor loses focus.

validationMessagePosition

Specifies the position of a validation message relative to the component. The validation message describes the validation rules that this component's value does not satisfy.

Type:

Position

|

Mode

Default Value: 'auto'

If you set this property to auto, the component specifies the validation message position automatically.

The following example positions a validation message at the component's right:

jQuery
index.js
$(function() {
    $("#dropDownBoxContainer").dxDropDownBox({
        // ...
        validationMessagePosition: 'right'
    }).dxValidator({
        validationRules: [{
            type: 'required',
            message: 'Required',
        }],
    });
});
Angular
app.component.html
<dx-drop-down-box ...
    validationMessagePosition="right">
    <dx-validator>
        <dxi-validation-rule
            type="required"
            message="Required"
        >
        </dxi-validation-rule>
    </dx-validator>
</dx-drop-down-box>
Vue
App.vue
<template>
    <DxDropDownBox ...
        validation-message-position="right"
    >
        <DxValidator>
            <DxRequiredRule message="Required" />
        </DxValidator>
    </DxDropDownBox>
</template>

<script>
    // ...
</script>
React
App.js
import React from 'react';
// ...

function App() {
    return (
        <DropDownBox ...
            validationMessagePosition="right"
        >
            <Validator>
                <RequiredRule message="Required" />
            </Validator>
        </DropDownBox>
    ); 

};
export default App;

validationStatus

Indicates or specifies the current validation status.

Default Value: 'valid'

The following table illustrates the validation status indicators:

validationStatus Indicator
"pending" DevExtreme editor validation status: pending
"valid" DevExtreme editor validation status: valid
"invalid" DevExtreme editor validation status: invalid

When you assign "invalid" to validationStatus, you can also use the validationErrors array to set an error message as shown below:

jQuery
index.js
$(function() {
    const dropDownBox = $("#dropDownBoxContainer").dxDropDownBox({
        // ...
    }).dxDropDownBox("instance");

    function setInvalidStatus(message) {
        dropDownBox.option({
            validationStatus: "invalid",
            validationErrors: [{ message: message }]
        });
    }
});
Angular
app.component.html
app.component.ts
<dx-drop-down-box
    [validationStatus]="validationStatus"
    [validationErrors]="validationErrors">
</dx-drop-down-box>
// ...
export class AppComponent {
    validationStatus: string = "valid";
    validationErrors: any;
    // ...
    setInvalidStatus(message) {
        this.validationStatus = "invalid";
        this.validationErrors = [{ message: message }];
    }
}
Vue
App.vue
<template>
    <DxDropDownBox ...
        :validation-status="validationStatus"
        :validation-errors="validationErrors"
    />
</template>

<script>
    // ...
    export default {
        // ...
        data() {
            return {
                validationStatus: "valid",
                validationErrors: []
            }
        },
        methods: {
            setInvalidStatus(message) {
                this.validationStatus = "invalid";
                this.validationErrors = [{ message: message }];
            }
        }
    }
</script>
React
App.js
import React, { useState } from 'react';
// ...

function App() {
    const [validationStatus, setValidationStatus] = useState("valid");
    const [validationErrors, setValidationErrors] = useState([]);

    const setInvalidStatus = message => {
        setValidationStatus("invalid");
        setValidationErrors([{ message: message }]);
    }

    return (
        <DropDownBox
            validationStatus={validationStatus}
            validationErrors={validationErrors}
        />
    ); 

};
export default App;

value

Specifies the currently selected value. May be an object if dataSource contains objects, the store key is specified, and valueExpr is not set.

Type: any
Default Value: null
Raised Events: onValueChanged

When dataSource contains objects, you should define valueExpr to correctly identify data items. Otherwise, the component uses referential equality to compare objects. For example, when valueExpr is not specified and you assign an object with the same field and values as dataSource to the value property, these two objects are not equal, and the component displays nothing.

valueChangeEvent

Specifies the DOM events after which the UI component's value should be updated.

Type:

String

Default Value: 'change'

This property accepts a single event name or several names separated by spaces.

The recommended events are "keyup", "blur", "change", "input", and "focusout", but you can use other events as well.

See Also

valueExpr

Specifies which data field provides unique values to the UI component's value.

Type:

String

|

Function

Function parameters:
item:

Object

The current item's data object.

Return Value:

String

|

Number

|

Boolean

A unique item identifier.

Default Value: 'this'

When dataSource contains objects, you should define valueExpr to correctly identify data items. Otherwise, the component uses referential equality to compare objects, which may result in unexpected behavior.

If you use a store, the valueExpr property should have the same value as the key in the store. Alternatively, you can use this as a valueExpr but the key should be specified. Refer to the following article for more information: Troubleshooting - A Drop-Down Editor Does Not Show Data.

Do not use template as a valueExpr value.

NOTE
You cannot specify valueExpr as a function when the UI component is bound to a remote data source. This is because valueExpr is used in a filter the UI component sends to the server when querying data. Functions with custom logic cannot be serialized for this filter.
See Also

visible

Specifies whether the UI component is visible.

Type:

Boolean

Default Value: true

width

Specifies the UI component's width.

Type:

Number

|

String

|

Function

Return Value:

Number

|

String

The UI component's width.

Default Value: undefined

This property accepts a value of one of the following types:

  • Number
    The width in pixels.

  • String
    A CSS-accepted measurement of width. For example, "55px", "20vw", "80%", "auto", "inherit".

  • Function (deprecated since v21.2)
    Refer to the W0017 warning description for information on how you can migrate to viewport units.