Picker

Example#

<Picker label="Choose frequency" onSelectionChange={selected => console.log(selected)}>
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>

Content#

Picker follows the Collection Components API, accepting both static and dynamic forms of children. Similar to the Menu, Picker accepts an <Item> component, each with a uniqueKey prop. Basic usage of the Picker, seen in the example above, shows multiple options populated with a string. This implementation would be used when the list of options is finite and known.

The dynamic method (shown below) would be better suited to use if the options came from a data object such as values returned from an API call. Providing the data in this way allows for Picker to automatically cache the rendering of each item, which dramatically improves performance.

As seen below, an iterable list of options is passed to the Picker using the items prop. Each item accepts a uniqueKey prop, which is passed to the onSelectionChange handler to identify the selected item. Alternatively, if the item objects contain an id property, as shown in the example below, then this is used automatically and a uniqueKey prop is not required. See the events section for more detail on selection.

function Example() {
  let options = [
    {id: 1, name: 'Aardvark'},
    {id: 2, name: 'Cat'},
    {id: 3, name: 'Dog'},
    {id: 4, name: 'Kangaroo'},
    {id: 5, name: 'Koala'},
    {id: 6, name: 'Penguin'},
    {id: 7, name: 'Snake'},
    {id: 8, name: 'Turtle'},
    {id: 9, name: 'Wombat'}
  ];

  return (
    // Dynamic Items
    <Picker label="Pick an animal" items={options} onSelectionChange={selected => console.log(selected)}>
      {item => <Item>{item.name}</Item>}
    </Picker>
  );
}

Internationalization#

To internationalize a Picker, a localized string should be passed to the children of each Item. For languages that are read right to left (e.g. Hebrew and Arabic), the layout of the Picker is flipped.

Labeling#

Picker can be labeled using the label prop. If no label is provided, an alternative text label must be provided to identify the control for accessibility. This should be added using the aria-label prop. If the Picker is a required field, the isRequired and necessityIndicator props can be used to show a required state.

<Picker label="Choose frequency" isRequired necessityIndicator="icon" marginEnd="10px">
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>
<Picker label="Choose frequency" isRequired necessityIndicator="label" marginEnd="10px">
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>
<Picker label="Choose frequency" necessityIndicator="label">
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>

Selection#

Setting a selected option can be done by using the defaultSelectedKey or selectedKey prop. The selected key corresponds to the uniqueKey of an item. See Events for more details on selection events.

function Example() {
  let options = [
    {name: 'Koala'},
    {name: 'Kangaroo'},
    {name: 'Platypus'},
    {name: 'Bald Eagle'},
    {name: 'Bison'},
    {name: 'Skunk'}
  ];
  let [animal, setAnimal] = React.useState("Bison");

  return (
    <>
      <Picker
        label="Pick an animal (uncontrolled)"
        items={options}
        defaultSelectedKey="Bison"
        marginEnd="20px">
        {item => <Item uniqueKey={item.name}>{item.name}</Item>}
      </Picker>

      <Picker
        label="Pick an animal (controlled)"
        items={options}
        selectedKey={animal}
        onSelectionChange={selected => setAnimal(selected)}>
        {item => <Item uniqueKey={item.name}>{item.name}</Item>}
      </Picker>
    </>
  );
}

Sections#

Picker supports sections in order to group options. Sections can be used by wrapping groups of Items in a Section component. Each Section takes a title and uniqueKey prop.

Static items#

<Picker label="Pick your favorite">
  <Section title="Animals">
    <Item uniqueKey="Aardvark">Aardvark</Item>
    <Item uniqueKey="Kangaroo">Kangaroo</Item>
    <Item uniqueKey="Snake">Snake</Item>
  </Section>
  <Section title="People">
    <Item uniqueKey="Danni">Danni</Item>
    <Item uniqueKey="Devon">Devon</Item>
    <Item uniqueKey="Ross">Ross</Item>
  </Section>
</Picker>

Dynamic items#

Sections used with dynamic items are populated from a hierarchical data structure. Similarly to the props on Picker, Section takes an array of data using the items prop.

function Example() {
  let options = [
    {name: 'Australian', children: [
      {id: 2, name: 'Koala'},
      {id: 3, name: 'Kangaroo'},
      {id: 4, name: 'Platypus'}
    ]},
    {name: 'American', children: [
      {id: 6, name: 'Bald Eagle'},
      {id: 7, name: 'Bison'},
      {id: 8, name: 'Skunk'}
    ]}
  ];

  return (
    <>
      <Picker label="Pick an animal" items={options} onSelectionChange={selected => alert(selected)}>
        {item => (
          <Section uniqueKey={item.name} items={item.children} title={item.name}>
            {item => <Item>{item.name}</Item>}
          </Section>
        )}
      </Picker>
    </>
  );
}

Events#

Picker supports selection via mouse, keyboard, and touch. You can handle all of these via the onSelectionChange prop. Picker will pass the selected uniqueKey to the onSelectionChange handler.

The following example uses an onSelectionChange handler to update the selection stored in React state.

function StaticExample() {
  let [frequency, setFrequency] = React.useState();

  return (
    <>
      <Picker label="Choose frequency" onSelectionChange={selected => setFrequency(selected)}>
        <Item uniqueKey="Rarely">Rarely</Item>
        <Item uniqueKey="Sometimes">Sometimes</Item>
        <Item uniqueKey="Always">Always</Item>
      </Picker>
      <p>You selected {frequency}</p>
    </>
  );
}

When using Picker with dynamic items, selection works much the same way using uniqueKey. However, if your data already has an id property (as is common with many data sets), Picker can use that id without needing to specify a uniqueKey prop. The below example shows Picker using the id of each item from the items array as the selected value without the need for uniqueKey. Note that uniqueKey will always take precedence if set.

function DynamicExample() {
  let [animalId, setAnimalId] = React.useState();
  let options = [
    {id: 1, name: 'Aardvark'},
    {id: 2, name: 'Cat'},
    {id: 3, name: 'Dog'},
    {id: 4, name: 'Kangaroo'},
    {id: 5, name: 'Koala'},
    {id: 6, name: 'Penguin'},
    {id: 7, name: 'Snake'},
    {id: 8, name: 'Turtle'},
    {id: 9, name: 'Wombat'}
  ];

  return (
    <>
      <Picker label="Pick an animal" items={options} onSelectionChange={selected => setAnimalId(selected)}>
        {item => <Item>{item.name}</Item>}
      </Picker>
      <p>Your favorite animal has id: {animalId}</p>
    </>
  );
}

Complex items#

Items within Picker also allow for additional content used to better communicate options. Icons and descriptions can be added to the children of Item as shown in the example below. If a description is added, the prop slot="description" must be used to distinguish the different <Text> elements.

<Picker label="Options">
  <Section title="Permission">
    <Item textValue="Read">
      <Book size="S" />
      <Text>Read</Text>
      <Text slot="description">Read Only</Text>
    </Item>
    <Item textValue="Write">
      <Draw size="S" />
      <Text>Write</Text>
      <Text slot="description">Read and Write Only</Text>
    </Item>
    <Item textValue="Admin">
      <BulkEditUsers size="S" />
      <Text>Admin</Text>
      <Text slot="description">Full access</Text>
    </Item>
  </Section>
</Picker>

Asynchronous loading#

Picker supports loading data asynchronously, and will display a progress circle when the isLoading prop is set. It also supports infinite scrolling to load more data on demand as the user scrolls, via the onLoadMore prop.

This example uses the useAsyncList hook to handle loading the data. See the docs for more information.

import {useAsyncList} from '@react-stately/data';

function AsyncLoadingExample() {
  let list = useAsyncList({
    async load({signal, cursor}) {
      // If no cursor is available, then we're loading the first page.
      // Otherwise, the cursor is the next URL to load, as returned from the previous page.
      let res = await fetch(cursor || 'https://pokeapi.co/api/v2/pokemon', {signal});
      let json = await res.json();
      return {
        items: json.results,
        cursor: json.next
      };
    }
  });

  return (
    <Picker
      label="Pick a Pokemon"
      items={list.items}
      isLoading={list.isLoading}
      onLoadMore={list.loadMore}>
      {item => <Item uniqueKey={item.name}>{item.name}</Item>}
    </Picker>
  );
}

Props#

Visual options#

Label alignment#

<Picker label="Choose frequency" labelAlign="end">
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>

Label position#

<Picker label="Choose frequency" labelPosition="side">
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>

Quiet#

<Picker label="Choose frequency" isQuiet labelPosition="side">
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>

Disabled#

<Picker label="Choose frequency" isDisabled>
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>

Custom widths#

<Flex flexDirection="column">
  <Picker label="Choose frequency" width="size-6000">
    <Item uniqueKey="rarely">Rarely</Item>
    <Item uniqueKey="sometimes">Sometimes</Item>
    <Item uniqueKey="always">Always</Item>
  </Picker>

  <Picker label="Choose animal" menuWidth="size-6000">
    <Item uniqueKey="Emu">Emu</Item>
    <Item uniqueKey="Kangaroo">Kangaroo</Item>
    <Item uniqueKey="Platypus">Platypus</Item>
  </Picker>
</Flex>

Align and direction#

<Flex flexDirection="column">
  <Picker label="Choose frequency" align="end" menuWidth="size-3000">
    <Item uniqueKey="rarely">Rarely</Item>
    <Item uniqueKey="sometimes">Sometimes</Item>
    <Item uniqueKey="always">Always</Item>
  </Picker>

  <Picker label="Choose animal" direction="top">
    <Item uniqueKey="Emu">Emu</Item>
    <Item uniqueKey="Kangaroo">Kangaroo</Item>
    <Item uniqueKey="Platypus">Platypus</Item>
  </Picker>
</Flex>

Menu state#

The open state of the menu can be controlled via the defaultOpen and isOpen props

<Picker label="Choose frequency" isOpen>
  <Item uniqueKey="rarely">Rarely</Item>
  <Item uniqueKey="sometimes">Sometimes</Item>
  <Item uniqueKey="always">Always</Item>
</Picker>