The autocomplete component is an input field that provides selectable options as a user types into it. It allows users to quickly search through and select from large collections of options.
How to use Autocomplete
The Autocomplete requires 3 props to work:
items
: Itβs an array containing the items that will be shown as selectable options when the user types something in theTextInput
.onInputValueChange
: This function will be called every time the user types something in the input. The component will pass theitem
, which the filter method is currently iterating over, and theinputValue
prop of theTextInput
component.onSelectItem
: This function is called when the user selects one of the options of the list. The component will pass the selected item as an argument to the function.
An Autocomplete
with a list of fruits will look like this:
Best practices
- Autocomplete should have a clear label so user understands what type of action is possible
- Consider using autocomplete over selects if a user will be choosing from a very long list, for example a country list.
Code examples
items
Using objects as On the example in the "How to use Autocomplete" section, we showed how to create an Autocomplete with an array of string
but itβs also possible to use other types of data as items
. A very common way of using the Autocomplete is with objects and for that, with a few changes
to the Fruitβs example this can be done:
Both itemToString
and renderItem
are necessary when passing objects as items and they both will receive an "item" as an argument.
If you are using Typescript, you can tell the Autocomplete what is the type of your items to make these functions strongly typed.
You can do that by writing the component like this <Autocomplete<ItemType> {...props}/>
getStringMatch
Highlighting an item with A common use case for Autocomplete components is to highlight in each suggestion what is typed in the input.
Using the previous example, if a user types "ana" we want to show a list of suggestions where only "ana" is bold.
This is possible by using the renderItem
prop and the getStringMatch
utility function:
// We need to import the function from the `f36-utils` packageimport { getStringMatch } from '@contentful/f36-utils';import { Autocomplete } from '@contentful/f36-autocomplete';// Everything stays the same, besides the `renderItem` prop<Autocompleteitems={filteredItems}onInputValueChange={handleInputValueChange}onSelectItem={handleSelectItem}itemToString={(item) => item.name}// Two arguments are provided to the `renderItem` prop: the item and the inputValuerenderItem={(item, inputValue) => {// we pass `item.name` and the inputValue to getStringMatch and the util will return an object// for our example, for the "Banana" item this will return { before: 'B' , match: 'ana', after: 'na' }const { before, match, after } = getStringMatch(item.name, inputValue);// Finally, we return a ReactNode// this will return `<>B<b>ana</b>na π</>` (the "ana" will be bold)return (<>{before}<b>{match}</b>{after} {item.emoji}</>);}}/>;
Filling in a list of items
items
Using grouped objects as As an extension of "Use objects as items" section, you are also able to use a nested object to group your entries.
The most important part of making this work is the shape of the grouped object. The options themselves work exactly as in the object example and require the itemToString
and renderItem
functions.
Besides the correct shape of the object the Autocomplete component needs to receive the prop isGrouped
Error validation with FormControl
Fetching async data
Content guidelines
- Autocomplete label should be short, contain 1 to 3 words
- Label should be written in a sentence case (the first word capitalized, the rest lowercase)
Accessibility
- dismisses the dropdown when selecting with the enter key
Props
- Name
items(required)
DescriptionItβs an array of data to be used as "options" by the autocomplete component. This can either be a plain list of items or a list of groups of items.
T[]GenericGroupType<T>[] - Name
onSelectItem(required)
DescriptionThis is the function that will be called when the user selects one of the "options" in the list. It receives the selected item as an argument and it needs to return a string that will be set as the value of `TextInput`.
(item: T) => void - Name
className
DescriptionCSS class to be appended to the root element
string - Name
clearAfterSelect
DescriptionIf this is set to `true` the text input will be cleared after an item is selected
falsetrue - Name
defaultValue
DescriptionSet's default value for text input
string - Name
id
DescriptionSets the id of the input
string - Name
inputRef
DescriptionUse this prop to get a ref to the input element of the component
(instance: HTMLInputElement) => voidRefObject<HTMLInputElement> - Name
isDisabled
DescriptionApplies disabled styles
falsetrue - Name
isGrouped
DescriptionTells if the item is a object with groups
falsetrue - Name
isInvalid
DescriptionApplies invalid styles
falsetrue - Name
isLoading
DescriptionSets the list to show its loading state
falsetrue - Name
isReadOnly
DescriptionApplies read-only styles
falsetrue - Name
isRequired
DescriptionValidate the input
falsetrue - Name
itemToString
DescriptionWhen using objects as `items`, we recommend passing a function that tells Downshift how to extract a string from those objetcs to be used as inputValue
(item: T) => string - Name
listMaxHeight
DescriptionIt sets the max-height, in pixels, of the list The default value is the height of 5 single line items
number - Name
listRef
DescriptionUse this prop to get a ref to the list of items of the component
(instance: HTMLUListElement) => voidRefObject<HTMLUListElement> - Name
listWidth
DescriptionIt sets the width of the list
"auto""full" - Name
noMatchesMessage
DescriptionA message that will be shown when it is not possible to find any option that matches the input value
string - Name
onInputValueChange
DescriptionFunction called whenever the input value changes
(value: string) => void - Name
placeholder
DescriptionThis is the value will be passed to the `placeholder` prop of the input.
string - Name
renderItem
DescriptionThis is the function that will be called for each "item" passed in the `items` prop. It receives the "item" and "inputValue" as arguments and returns a ReactNode. The inputValue is passed in case you want to highlight the match on the render.
(item: T, inputValue: string) => ReactNode - Name
testId
DescriptionA [data-test-id] attribute used for testing purposes
string - Name
toggleRef
DescriptionUse this prop to get a ref to the toggle button of the component
(instance: HTMLButtonElement) => voidRefObject<HTMLButtonElement> - Name
usePortal
DescriptionBoolean to control whether or not to render the suggestions box in a React Portal. Rendering content inside a Portal allows the suggestions box to escape the bounds of its parent while still being positioned correctly. Defaults to `false`
falsetrue