Configuration

An object defining configuration options for the TagBox widget.

acceptCustomValue

Specifies whether the widget allows a user to enter a custom value. Requires the onCustomItemCreating handler implementation.

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.

applyValueMode

Specifies how the widget applies values.

Type:

String

Default Value: 'instantly'
Accepted Values: 'useButtons' | 'instantly'

The option accepts the following values.

  • instantly
    Applies values when they are selected.

  • useButtons
    Applies values when a user clicks the "OK" button.

When using the widget as an ASP.NET MVC Control, specify this option using the EditorApplyValueMode enum. This enum accepts the following values: Instantly and UseButtons.

attr

Deprecated

Use the inputAttr option instead.

dataSource

A data source used to fetch data to be displayed by the widget.

Default Value: null

This option accepts one of the following.

  • Array of objects
    A simple JavaScript array containing a collection of plain objects.

  • URL
    A URL to JSON data or to a service returning data in JSON format.

  • DataSource or its configuration object
    A DataSource is an object that provides a handy API for data processing. A DataSource is a stateful object, which means that it saves data processing settings and applies them each time data is loaded. All underlying data access logic of a DataSource is isolated in a Store. A Store provides an API for reading and modifying data. Unlike the DataSource, a Store is a stateless object.

NOTE
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.
Show Example:
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deferRendering

Specifies whether widget content is rendered when the widget is shown or when rendering the widget.

Type:

Boolean

Default Value: true

If this option is set to true, widget content is rendered when showing the widget. Otherwise, widget content is rendered when rendering the widget.

disabled

Specifies whether the widget responds to user interaction.

Type:

Boolean

Default Value: false

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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.

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dropDownButtonTemplate

Specifies a custom template for the drop-down button.

Type:

template

Function parameters:
buttonData:

Object

Information about the button.

Object structure:
text:

String

The button's text.

icon:

String

The button's icon.

contentElement:

Element (jQuery or HTML)

The button's container.

Return Value:

String

|

DOM Node

|

jQuery

A template name or container.

Default Value: 'dropDownButton'

elementAttr

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

Type:

Object

Default Value: {}

You can configure this option in an ASP.NET MVC Control as follows:

Razor C#
Razor VB
@(Html.DevExtreme().WidgetName()
    .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().WidgetName() _
    .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" }
    })
)

fieldEditEnabled

Deprecated

Use the acceptCustomValue option instead.

fieldTemplate

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

Type:

template

Function parameters:
selectedItem:

Object

The selected item's data.

fieldElement:

Element (jQuery or HTML)

The field's container.

Return Value:

String

|

DOM Node

|

jQuery

A template name or container.

Default Value: null

focusStateEnabled

Specifies whether the widget can be focused using keyboard navigation.

Type:

Boolean

Default Value: true

grouped

Specifies whether data items should be grouped.

Type:

Boolean

Default Value: false

When this option is true, make sure that all data source objects have the following structure:

JavaScript
var dataSource = [{
    key: "Group 1", // Group caption 
    items: [ // Items in the group
        { ... },
        { ... }
    ]
}, {
    // ...
}];

You can supply data to this structure using the DataSource object's group option.

NOTE
Only one-level grouping is supported.
See Also

groupTemplate

Specifies a custom template for group captions.

Type:

template

Function parameters:
itemData:

Object

The group's data.

itemIndex:

Number

The group's index.

itemElement:

Element (jQuery or HTML)

The group's container.

Return Value:

String

|

DOM Node

|

jQuery

A template name or container.

Default Value: 'group'

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;
    }

hideSelectedItems

A Boolean value specifying whether or not to hide selected items.

Type:

Boolean

Default Value: false

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: {}

You can configure this option in an ASP.NET MVC Control as follows:

Razor C#
Razor VB
@(Html.DevExtreme().WidgetName()
    .InputAttr("id", "inputId")
    // ===== or =====
    .InputAttr(new {
        @id = "inputId"
    })
    // ===== or =====
    .InputAttr(new Dictionary<string, object>() {
        { "id", "inputId" }
    })
)
@(Html.DevExtreme().WidgetName() _
    .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.

itemTemplate

Specifies a custom template for items.

Type:

template

Function parameters:
itemData:

Object

The current item's data.

itemIndex:

Number

The current item's index.

itemElement:

Element (jQuery or HTML)

The current item's container.

Return Value:

String

|

DOM Node

|

jQuery

A template name or container.

Default Value: 'item'
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maxDisplayedTags

Specifies the limit on displayed tags. On exceeding it, the widget replaces all tags with a single multi-tag that displays the number of selected items.

Type:

Number

Default Value: undefined

minSearchLength

The minimum number of characters that must be entered into the text box to begin a search. Applies only if searchEnabled is true.

Type:

Number

Default Value: 0

multiline

A Boolean value specifying whether or not the widget is multiline.

Type:

Boolean

Default Value: true

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.

noDataText

The text or HTML markup displayed by the widget if the item collection is empty.

Type:

String

Default Value: 'No data to display'

onChange

A handler for the change event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action when a change within the widget's input element is committed by an end user.

onClosed

A handler for the closed event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

Default Value: null

Assign a function to perform a custom action after a drop-down editor has been hidden.

onContentReady

A handler for the contentReady event. Executed when the widget's content is ready. This handler may be executed multiple times during the widget's lifetime depending on the number of times its content changes.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only when using Knockout.

Default Value: null

If data displayed by the widget is specified using a DataSource instance, the contentReady event fires each time the load() method of the DataSource instance is called as well as when widget content is ready. In this case, when you create the widget, the contentReady event is raised twice: when the widget's content is ready (at this moment, the widget does not display items) and when the DataSource is loaded (the widget displays the loaded items).

onCustomItemCreating

A handler for the customItemCreating event. Executed when a user adds a custom item. Requires acceptCustomValue to be set to true.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if you use Knockout.

text:

String

The input field's text.

customItem:

String

|

Object

|

Promise<any> (jQuery or native)

The field where to place a custom item.

Return Value:

String

|

Object

|

Promise<any> (jQuery or native)

A custom item or a Promise that is resolved after the item is created. It is a native Promise or a jQuery.Promise when you use jQuery.

Default Value: function(e) { e.customItem = e.text; }

onDisposing

A handler for the disposing event. Executed when the widget is removed from the DOM using the remove(), empty(), or html() jQuery methods only.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if you use Knockout.

Default Value: null

onEnterKey

A handler for the enterKey event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action after the 'Enter' key is pressed within the widget's input element.

onFocusIn

A handler for the focusIn event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action after the widget's input is focused.

onFocusOut

A handler for the focusOut event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action after the widget's input element loses focus.

onInitialized

A handler for the initialized event. Executed only once, after the widget is initialized.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

Default Value: null

You cannot access widget elements in this handler because it is executed before they are ready. Use the onContentReady handler instead.

onInput

A handler for the input event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action when a value within the widget's input element is changed by an end user.

onItemClick

A handler for the itemClick event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

itemData:

Object

The clicked item's data.

itemElement:

Object

The item's container.

itemIndex:

Number

|

Object

The clicked item's index. If the widget items are grouped, the index represents an object defining the group and item indexes: { group: 0, item: 0 }.

Default Value: null

Assign a function to perform a custom action when a widget item is clicked.

To navigate to a specific URL when the itemClick event fires, assign that URL directly to this option.

onKeyDown

A handler for the keyDown event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action when a key is pressed down within the widget's input element.

onKeyPress

A handler for the keyPress event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action when the keypress DOM event is raised for the current input element.

onKeyUp

A handler for the keyUp event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

jQueryEvent:

jQuery.Event

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action when a key is released within the widget's input element.

onMultiTagPreparing

A handler for the multiTagPreparing event. Executed before the multi-tag is rendered.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only when using Knockout.

multiTagElement:

Element (jQuery or HTML)

The multi-tag's container.

selectedItems:

Array<String | Number | Object>

The currently selected items.

text:

String

Allows you to change the multi-tag's text.

cancel:

Boolean

Allows you to cancel replacing ordinary tags with the multi-tag.

Default Value: null

onOpened

A handler for the opened event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

Default Value: null

Assign a function to perform a custom action when the drop-down editor is shown.

onOptionChanged

A handler for the optionChanged event. Executed after an option of the widget is changed.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

name:

String

The option's short name.

fullName:

String

The option's full name.

value: any

The option's new value.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if you use Knockout.

Default Value: null

onSelectAllValueChanged

A handler for the selectAllValueChanged event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

value:

Boolean

The "Select All" check box's state.

Default Value: null

Assign a function to perform a custom action when the select all check box value is changed.

Note that this event fires only if the showSelectionControls option is set to true.

onSelectionChanged

A handler for the selectionChanged event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

model:

Object

The model data. Available only if Knockout is used.

addedItems:

Array<String | Number | Object>

The data of the items that have been selected.

removedItems:

Array<String | Number | Object>

The data of the items whose selection has been canceled.

Default Value: null

Assign a function to perform a custom action when the selection changes.

onValueChanged

A handler for the valueChanged event.

Type:

function

Function parameters:
e:

Object

Information about the event.

Object structure:
component:

Object

The widget's instance.

element:

Element (jQuery or HTML)

The widget's container.

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

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

event:

Event (jQuery or dxEvent)

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

Default Value: null

Assign a function to perform a custom action when the editor value changes.

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opened

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

Type:

Boolean

Default Value: false

pagingEnabled

Deprecated

Use the paginate option instead.

Specifies whether or not the widget displays items by pages.

Type:

Boolean

Default Value: undefined

placeholder

The text that is provided as a hint in the select box editor.

Type:

String

Default Value: 'Select'

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
});

searchEnabled

Specifies whether to allow searching.

Type:

Boolean

Default Value: false

searchExpr

Specifies the name of a data source item field or an expression whose value is compared to the search criterion.

Type:

getter

|

Array<getter>

Default Value: null

In most cases, you should pass the name of a field by whose value data items are searched. If you need to search elements by several field values, assign an array of field names to this option.

JavaScript
searchExpr: ["firstName", "lastName"]

For more information on searching, refer to the Search Api section of the Data Layer article. For information on getters, refer to the Getters and Setters section of the Data Layer article.

searchMode

Specifies the binary operation used to filter data.

Type:

String

Default Value: 'contains'
Accepted Values: 'contains' | 'startswith'

When using the widget as an ASP.NET MVC Control, specify this option using the DropDownSearchMode enum. This enum accepts the following values: Contains and StartsWith.

searchTimeout

Specifies the time delay, in milliseconds, after the last character has been typed in, before a search is executed.

Type:

Number

Default Value: 500

selectAllMode

Specifies the mode in which all items are selected.

Type:

String

Default Value: 'page'
Accepted Values: 'page' | 'allPages'

The selectAllMode specifies how records should be selected on clicking the "Select All" check box. The following modes are available.

  • 'page'
    Selects items on the currently rendered pages.

  • 'allPages'
    Selects items on all pages.

selectedItems

Gets the currently selected items.

Type:

Array<String | Number | Object>

Read-only
NOTE
This option is read-only.

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.

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showDataBeforeSearch

Specifies whether or not the widget displays unfiltered values until a user types a number of characters exceeding the minSearchLength option value.

Type:

Boolean

Default Value: false

If this option is disabled, the widget does not display values until the number of typed characters exceeds the minSearchLength value, otherwise it displays all values regardless of the specified filtering condition.

showMultiTagOnly

Specifies whether the multi-tag is shown without ordinary tags.

Type:

Boolean

Default Value: true

showSelectionControls

Specifies whether or not to display selection controls.

Type:

Boolean

Default Value: false

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.

tagTemplate

Specifies a custom template for tags.

Type:

template

Function parameters:
itemData:

Object

The current tag's data.

itemElement:

Element (jQuery or HTML)

The tag's container.

Return Value:

String

|

DOM Node

|

jQuery

A template name or container.

Default Value: 'tag'
Show Example:
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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: 'auto' | 'always'

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.

When using the widget as an ASP.NET MVC Control, specify this option using the ValidationMessageMode enum. This enum accepts the following values: Auto and Always.

value

Specifies the selected items.

Type:

Array<String | Number | Object>

Pass an array of items to this option to select them.

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'

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values

Deprecated

Use the value option instead.

Show Example:
AngularJS
Knockout
jQuery

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;
    }