Angular DropDownBox Properties

An object defining configuration options for the DropDownBox widget.

acceptCustomValue

Specifies whether the widget allows a user to enter a custom value.

Type:

Boolean

Default Value: false

accessKey

Specifies the shortcut key that sets focus on the widget.

Type:

String

Default Value: null

The value of this option will be passed to the accesskey attribute of the HTML element that underlies the widget.

activeStateEnabled

Specifies whether or not the widget changes its state when interacting with a user.

Type:

Boolean

Default Value: true

This option is used when the widget is displayed on a platform whose guidelines include the active state change for widgets.

contentTemplate

Specifies a custom template for the drop-down content.

Type:

template

Template Data:
Name Type Description
component

DropDownBox

The widget's instance.

value any

The currently selected value.

Default Name: null

dataSource

A data source used to fetch data the widget should display.

Default Value: null

This option accepts one of the following:

  • Array
    A JavaScript array that contains string, numeric, Boolean values, or plain objects.

  • URL
    The URL of a JSON file or service that returns JSON data.

  • DataSource or its configuration object
    The DataSource is an object that provides an API for data processing. The DataSource's underlying data access logic is isolated in a store. Refer to the Data Layer and DataSource Examples guides for more information about the DataSource.

If the data source contains objects, specify the key in the store and/or a data field providing values in the widget.

NOTE
Data field names should not contain the following characters: ., ,, :, [, and ]. Their presence may cause issues in the widget's operation.

If the data source is specified using the dataSource option, use the items option only for reading. Updating data items using the items option may cause unexpected results.

See Also

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

disabled

Specifies whether the widget responds to user interaction.

Type:

Boolean

Default Value: false

displayExpr

Specifies the name of the data source item field whose value is displayed by the widget.

Type:

String

|

Function

Default Value: undefined

If the data source item is a simple object holding a value (string, numeric, Boolean, etc.), assign "this" to the displayExpr option. If the item is a plain object item, assign the required field name or path to the option.

dropDownButtonTemplate

Specifies a custom template for the drop-down button.

Type:

template

Template Data:
Name Type Description
text

String

The button's text.

icon

String

The button's icon.

Default Name: 'dropDownButton'

dropDownOptions

Configures the drop-down field which holds the content.

Default Value: {}

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

NOTE
The fields of a configuration object passed to this option do not support two-way binding in Angular, AngularJS, and Knockout and event bindings in Angular.

elementAttr

Specifies the attributes to be attached to the widget's root element.

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
    ],
    // ...
})
ASP.NET MVC Control
Razor C#
Razor VB
@(Html.DevExtreme().DropDownBox()
    .ElementAttr("class", "class-name")
    // ===== or =====
    .ElementAttr(new {
        @id = "elementId",
        @class = "class-name"
    })
    // ===== or =====
    .ElementAttr(new Dictionary<string, object>() {
        { "id", "elementId" },
        { "class", "class-name" }
    })

)
@(Html.DevExtreme().DropDownBox() _
    .ElementAttr("class", "class-name")
    ' ===== or =====
    .ElementAttr(New With {
        .id = "elementId",
        .class = "class-name"
    })
    ' ===== or =====
    .ElementAttr(New Dictionary(Of String, Object) From {
        { "id", "elementId" },
        { "class", "class-name" }
    })
)

fieldTemplate

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

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
JavaScript
CSS
$(function () {
    $("dropDownBoxContainer").dxDropDownBox({
        // ...
        fieldTemplate: function (value, fieldElement) {
            var result = $("<div class='custom-item'>");
            result
                .dxTextBox({
                    value: value,
                    readOnly: true 
                });
            fieldElement.append(result);
        }
    });
});
.custom-item {
    font-size: 16px;
}
Angular
HTML
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;
}
AngularJS
HTML
CSS
<div dx-drop-down-box="{
    ...
    fieldTemplate: 'field'
}" dx-item-alias="data">
    <div data-options="dxTemplate: { name: 'field' }">
        <div class="custom-item">
            <div dx-text-box="{ value: data, readOnly: true }"></div>
        </div>
    </div>
</div>
.custom-item {
    font-size: 16px;
}
Knockout
HTML
CSS
<div data-bind="dxDropDownBox: {
    ...
    fieldTemplate: 'field'
}">
    <div data-options="dxTemplate: { name: 'field' }">
        <div class="custom-item">
            <div data-bind="dxTextBox: { value: $data, readOnly: true }"></div>
        </div>
    </div>
</div>
.custom-item {
    font-size: 16px;
}
See Also

focusStateEnabled

Specifies whether the widget can be focused using keyboard navigation.

Type:

Boolean

Default Value: true

height

Specifies the widget's height.

Type:

Number

|

String

|

Function

Return Value:

Number

|

String

The widget's height.

Default Value: undefined

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

  • Number
    The height in pixels.

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

  • Function
    A function returning either of the above. For example:

    JavaScript
    height: function() {
        return window.innerHeight / 1.5;
    }

hint

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

Type:

String

Default Value: undefined

hoverStateEnabled

Specifies whether the widget 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:

Object

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
    ],
    // ...
})
ASP.NET MVC Control
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" }
    })
)

isValid

Specifies whether the editor's value is valid.

Type:

Boolean

Default Value: true

In Knockout apps, you may need to inform a user about an error that occurred during the validation of a view model field. For this purpose, set the editor's isValid option to the isValid value of the dxValidator that validates this field. To show an error message, set the editor's validationError option to the dxValidator's validationError value.

JavaScript
var editorValue = ko.observable("").extend({
    dxValidator: {
        validationRules: [{
            type: "required",
            message: "Specify this value"
        }]
    }
});
var viewModel = {
    editorOptions: {
        value: editorValue,
        isValid: editorValue.dxValidator.isValid,
        validationError: editorValue.dxValidator.validationError
    }
};

The editor's isValid and validationError options should also be specified when using a custom validation engine. In this instance, the validation result will be displayed for the editor by the means of the DevExtreme Validation UI.

See Also

items

An array of items displayed by the widget.

Type:

Array<any>

You can use the dataSource option instead. Unlike the items option, the dataSource option can take on the DataSource configuration object as well as a simple array.

NOTE
If you need to modify the data source specified using the items option at runtime, do it only with the help of the items option. Updating data items using the dataSource option may cause unexpected results.

name

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

Type:

String

Default Value: ''

Specify this option if the widget lies within an HTML form that will be submitted.

If you configure the widget as an ASP.NET MVC Control, use this option to bind the widget to a model property. If this model property contains Data Annotation validation attributes, you get the client-side validation enabled by default.

onChange

A function that is executed when the widget loses focus after the content has been changed.

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onClosed

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

Default Value: null

onCopy

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onCut

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onDisposing

A function that is executed before the widget is disposed of.

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if you use Knockout.

Default Value: null

onEnterKey

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onFocusIn

A function that is executed when the widget gets focus.

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

model

Object

The model data. Available only if Knockout is used.

element

HTMLElement | jQuery

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

component

DropDownBox

The widget's instance.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onFocusOut

A function that is executed when the widget loses focus.

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

model

Object

The model data. Available only if Knockout is used.

element

HTMLElement | jQuery

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

component

DropDownBox

The widget's instance.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onInitialized

A function that is executed only once, after the widget is initialized.

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

Default Value: null

You cannot access widget elements in this function because it is executed before they are ready.

onInput

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onKeyDown

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onKeyPress

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onKeyUp

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onOpened

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

Default Value: null

onOptionChanged

A function that is executed after a widget option is changed.

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
name

String

The option's short name.

model

Object

The model data. Available only if you use Knockout.

element

HTMLElement | jQuery

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

component

DropDownBox

The widget's instance.

fullName

String

The option's full name.

value any

The option's new value.

Default Value: null

onPaste

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

onValueChanged

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

Type:

Function

Function parameters:
e:

Object

Information about the event.

Object structure:
Name Type Description
component

DropDownBox

The widget's instance.

element

HTMLElement | jQuery

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

model

Object

The model data. Available only if Knockout is used.

value

Object

The widget's new value.

previousValue

Object

The widget's previous value.

jQueryEvent

jQuery.Event

Use 'event' instead.

The jQuery event that caused the handler execution. Deprecated in favor of the event field.

event

Event (jQuery or EventObject)

The event that caused the handler execution. It is a dxEvent or a jQuery.Event when you use jQuery.

Default Value: null

opened

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

Type:

Boolean

Default Value: false
Raised Events: onOpened onClosed

placeholder

The text displayed by the widget when the widget value is empty.

Type:

String

Default Value: ''

readOnly

A Boolean value specifying whether or not the widget is read-only.

Type:

Boolean

Default Value: false

rtlEnabled

Switches the widget to a right-to-left representation.

Type:

Boolean

Default Value: false

When this option is set to true, the widget 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
});
See Also

showClearButton

Specifies whether to display the Clear button in the widget.

Type:

Boolean

Default Value: false

The Clear button sets the widget value to null.

showDropDownButton

Specifies whether to show the drop-down button.

Type:

Boolean

Default Value: true

tabIndex

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

Type:

Number

Default Value: 0

The value of this option will be passed to the tabindex attribute of the HTML element that underlies the widget.

text

The read-only option that holds the text displayed by the widget input element.

Type:

String

Read-only

validationError

Specifies information on the validation error when using a custom validation engine. Should be changed at runtime along with the isValid option.

Type:

Object

Default Value: undefined

validationMessageMode

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

Type:

String

Default Value: 'auto'
Accepted Values: 'always' | 'auto'

The following option 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.

Use the ValidationMessageMode enum to specify this option when the widget is used as an ASP.NET MVC Control. This enum accepts the following values: Auto and Always.

value

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

Type: any
Default Value: null
Raised Events: onValueChanged

valueChangeEvent

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

Type:

String

Default Value: 'change'

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

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

valueExpr

Specifies which data field provides the widget's value. When this option is not set, the value is the entire data object.

Type:

String

|

Function

Default Value: 'this'

visible

Specifies whether the widget is visible.

Type:

Boolean

Default Value: true

width

Specifies the widget's width.

Type:

Number

|

String

|

Function

Return Value:

Number

|

String

The widget's width.

Default Value: undefined

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

  • Number
    The width in pixels.

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

  • Function
    A function returning either of the above. For example:

    JavaScript
    width: function() {
        return window.innerWidth / 1.5;
    }