A widget that provides an input field that is readonly, accompanied by a dropdown list of selectable options.
For Use In
Lightning Experience, Experience Builder Sites, Salesforce Mobile App, Lightning Out (Beta), Standalone Lightning App, Mobile Offline
lightning-combobox is an input element that enables single selection from a
list of options. The result of the selection corresponds to the value of the
input. Multiple selection is not supported. To support multiple selection, use lightning-dual-listbox instead.
This example creates a list of options with a default selection that’s specified with the value attribute.
The options attribute specifies the name of an array of items for the dropdown list.
lightning-combobox implements the combobox blueprint in the Salesforce Lightning Design System (SLDS). The combobox adapts to SLDS 1 or SLDS 2 styling based on the org’s theme or the container app that you use.
In your JavaScript, define an array of options. Each option corresponds to a list item on the
dropdown list. Define the content of each option by specifying a value property and
a label property. The dropdown list shows the label that you provide by using the label value.
Select an item updates its corresponding value property.
Define an optional description property to add a line of descriptive text for each option. The
descriptive text appears below the label of the list item.
When adding descriptions, specify a description for each item in a list.
If some items are missing descriptions, the alignment of the items can appear incorrect.
1import{LightningElement}from "lwc";2export default class ComboboxExample extends LightningElement{3 statusOptions = [4{value: "new", label: "New", description: "A new item"},5{6 value: "in-progress",7 label: "In Progress",8 description: "Currently working on this item",9},10{11 value: "finished",12 label: "Finished",13 description: "Done working on this item",14},15];1617 value = "new";1819 handleChange(event){20 // Get the string of the "value" attribute on the selected option21 this.value = event.detail.value;22}23}
Selecting an option triggers the change event, which calls the
handleChange function. To check which option is clicked,
use event.detail.value.
Append an SLDS Icon
By default, the combobox options don’t include an icon. To include an SLDS icon on the options, use the button variant. This variant supports options with and without icons. Consider these icon behaviors:
To create a combobox that appears pill-like without an icon, use the button variant without specifying iconName on the options.
Input Validation
Client-side input validation is available for this component. You can require
the selection by adding the required attribute. An error message is
automatically shown when an item isn’t selected on a required element.
To check the validity states of an input, use the validity attribute, which
is based on the ValidityState object. You can access the validity states in
your JavaScript. This validity attribute returns an object with
boolean attributes. See lightning-input for more information.
You can override the default message by providing your own value for
message-when-value-missing.
Component Styling
Use a combination of variants and utility classes to customize your combobox styles.
Variants
Use the variant attribute with one of these values to apply styling.
label-hidden hides the label but make it available to assistive technology
label-inline horizontally aligns the label and combobox
label-stacked to place the label above the combobox
button presents a pill-shaped combobox with icon support. See Append an SLDS Icon.
Utility Classes
To apply additional styling, use the SLDS utility classes with the class attribute,
Usage Considerations
Special characters like " must be escaped. For example, you want to display
"New".
When you use single quotes in the value, escape the quote with a double slash
instead of a single slash.
lightning-combobox doesn’t currently support autocomplete or typeahead. The autocomplete attribute is reserved for internal use.
In Lightning Experience, a lightning-combobox dropdown list that’s opened overlays the record edit page or modal, the global header, and record form footer when scrolling.
On mobile devices, lightning-combobox has these limitations.
The dropdown menu doesn’t scroll correctly when there’s limited space to show the complete list of options.
The mobile viewport doesn’t display the dropdown menu correctly, especially if you place the component near the bottom of the page.
We recommend that you use the HTML <select> element on mobile instead.
Provide a text label for accessibility to make the information
available to assistive technology. The label attribute creates an HTML label
element for your component. To hide a label from view and make it
available to assistive technology, use the label-hidden variant.
When an option label is too long to fit in a single line, the label wraps and continues in a new line.
If a long word in an option label isn’t fully visible, scroll horizontally on the dropdown list to reveal the whole word.
Custom Events
change
The event fired when an item is selected in the combobox.
The change event returns this parameter.
Parameter
Type
Description
selectedValue
string
The value of the selected option.
The event properties are as follows.
Property
Value
Description
bubbles
true
This event bubbles up through the DOM.
cancelable
false
This event has no default behavior that can be canceled. You can’t call preventDefault() on this event.
composed
true
This event propagates outside of the component in which it was dispatched.
open
The event fired when the dropdown is opened.
The open event doesn’t return any parameters.
Property
Value
Description
bubbles
false
This event does not bubble.
cancelable
false
This event has no default behavior that can be canceled. You can’t call preventDefault() on this event.
composed
false
This event does not propagate outside of the component in which it was dispatched.
Attributes
Name
Description
Type
Default
Required
aria-described-by
Reserved for internal use. Use the standard aria-describedby instead. A space-separated list of element IDs that provide descriptive labels for the combobox.
string
aria-invalid
A Boolean value for aria-invalid.
boolean
aria-labelled-by
Reserved for internal use. Use the standard aria-labelledby instead. A space-separated list of element IDs that provide labels for the combobox.
string
autocomplete
Reserved for internal use. Controls auto-filling of the field.
string
disabled
If present, the combobox is disabled and users cannot interact with it.
boolean
false
dropdown-alignment
Specifies where the drop-down list is aligned with or anchored to the selection field. By default the list is aligned with the selection field at the top left so the list opens down. Use bottom-left to make the selection field display at the bottom so the list opens above it. Use auto to let the component determine where to open the list based on space available.
string
left
field-level-help
Help text detailing the purpose and function of the combobox.
string
icon-name
The name of the icon displayed in the combobox button. Applies only when variant is 'button'.
string
label
Text label for the combobox.
message-when-value-missing
Error message to be displayed when the value is missing and input is required.
string
name
Specifies the name of the combobox.
string
options
A list of options that are available for selection. Each option has the following attributes: label and value.
object[]
placeholder
Text that is displayed before an option is selected, to prompt the user to select an option. The default is "Select an Option".
string
Select
read-only
If present, the combobox is read-only. A read-only combobox is also disabled.
boolean
false
required
If present, a value must be selected before the form can be submitted.
boolean
false
spinner-active
If present, a spinner is displayed below the menu items to indicate loading activity.
boolean
false
validity
Represents the validity states that an element can be in, with respect to constraint validation.
object
value
Specifies the value of an input element.
string
variant
The variant changes the appearance of the combobox. Accepted variants include standard, label-hidden, label-inline, label-stacked, and button. This value defaults to standard. Use label-hidden to hide the label but make it available to assistive technology. Use label-inline to horizontally align the label and combobox. Use label-stacked to place the label above the combobox. Use button for a pill-shaped button-like combobox trigger.
string
standard
Methods
Name
Description
Argument Name
Argument Type
Argument Description
blur
Removes focus from the combobox.
checkValidity
Returns the valid attribute value (Boolean) on the ValidityState object.
focus
Sets focus on the combobox.
reportValidity
Displays the error messages and returns false if the input is invalid. If the input is valid, reportValidity() clears displayed error messages and returns true.
setCustomValidity
Sets a custom error message to be displayed when the combobox value is submitted.
message
string
The string that describes the error. If message is an empty string, the error message is reset.
showHelpMessageIfInvalid
Shows the help message if the combobox is in an invalid state.