react-native/docs/slider.md
Héctor Ramos 64d80b13db Migrate to new documentation format
Summary:
Now that the Component and API docs are no longer auto-generated, we need to consolidate on a new format for our jsdoc comments. Any help from the community will be appreciated.

In this initial pull request, we'll be tackling the following docs:

- `AccessibilityInfo`, an API doc.
- `ActivityIndicator`, a Component doc.
- `View`, a Component doc.

This top comment will serve as a style guide, and when in doubt, please refer to the individual commits in this PR.

Each commit should update a single component or API, along with any relevant markdown files.

- Documentation in the JavaScript source files should be succinct. Any verbosity should be moved over to the markdown docs in the website...
- ...by adding a link to the relevant method/prop on the website to every comment block.
- Avoid markdown style links in JavaScript source files, opt for plain old URIs.

Let code document itself:

- If a method is Flow typed, the comment block does not need to repeat this information.
- If a param can be one of several values, and the type definition is easily determined from the code, the values should not be repeated in the comment block. Again, move this to the markdown doc if not present already.
Closes https://github.com/facebook/react-native/pull/16790

Differential Revision: D6353840

Pulled By: hramos

fbshipit-source-id: 9712c459acc33092aae9909f3dd0b58a00b26afc
2017-11-16 17:04:45 -08:00

5.4 KiB

id title layout category permalink next previous
slider Slider docs components docs/slider.html snapshotviewios segmentedcontrolios

A component used to select a single value from a range of values.

Usage

The example below shows how to use Slider to change a value used by Text. The value is stored using the state of the root component (App). The same component subscribes to the onValueChange of Slider and changes the value using setState.

import React from 'react';
import { StyleSheet, Text, View, Slider } from 'react-native';

export default class App extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      value: 50
    }
  }

  change(value) {
    this.setState(() => {
      return {
        value: parseFloat(value)
      };
    });
  }

  render() {
    const {value} = this.state;
    return (
      <View style={styles.container}>
        <Text style={styles.text}>{String(value)}</Text>
        <Slider
          step={1}
          maximumValue={100}
          onValueChange={this.change.bind(this)}
          value={value} />
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    flexDirection: 'column',
    justifyContent: 'center'
  },
  text: {
    fontSize: 50,
    textAlign: 'center'
  }
});

Props


Reference

Props

style

Used to style and layout the Slider. See StyleSheet.js and ViewStylePropTypes.js for more info.

Type Required
ViewPropTypes.style No

disabled

If true the user won't be able to move the slider. Default value is false.

Type Required
bool No

maximumValue

Initial maximum value of the slider. Default value is 1.

Type Required
number No

minimumTrackTintColor

The color used for the track to the left of the button. Overrides the default blue gradient image on iOS.

Type Required
color No

minimumValue

Initial minimum value of the slider. Default value is 0.

Type Required
number No

onSlidingComplete

Callback that is called when the user releases the slider, regardless if the value has changed. The current value is passed as an argument to the callback handler.

Type Required
function No

onValueChange

Callback continuously called while the user is dragging the slider.

Type Required
function No

step

Step value of the slider. The value should be between 0 and (maximumValue - minimumValue). Default value is 0.

Type Required
number No

maximumTrackTintColor

The color used for the track to the right of the button. Overrides the default blue gradient image on iOS.

Type Required
color No

testID

Used to locate this view in UI automation tests.

Type Required
string No

value

Initial value of the slider. The value should be between minimumValue and maximumValue, which default to 0 and 1 respectively. Default value is 0.

This is not a controlled component, you don't need to update the value during dragging.

Type Required
number No

thumbTintColor

Color of the foreground switch grip.

Type Required Platform
color No Android

maximumTrackImage

Assigns a maximum track image. Only static images are supported. The leftmost pixel of the image will be stretched to fill the track.

Type Required Platform
Image.propTypes.source No iOS

minimumTrackImage

Assigns a minimum track image. Only static images are supported. The rightmost pixel of the image will be stretched to fill the track.

Type Required Platform
Image.propTypes.source No iOS

thumbImage

Sets an image for the thumb. Only static images are supported.

Type Required Platform
Image.propTypes.source No iOS

trackImage

Assigns a single image for the track. Only static images are supported. The center pixel of the image will be stretched to fill the track.

Type Required Platform
Image.propTypes.source No iOS