Storybook Addon Knobs

Storybook Addon Knobs allow you to edit React props dynamically using the Storybook UI. You can also use Knobs as a dynamic variable inside stories in Storybook.

Framework Support

This is how Knobs look like:

Checkout the above Live Storybook or watch this video.

Getting Started

First of all, you need to install knobs into your project as a dev dependency.

npm install @storybook/addon-knobs --save-dev

Then, configure it as an addon by adding it to your addons.js file (located in the Storybook config directory).

import '@storybook/addon-knobs/register'

Now, write your stories with knobs.

With React

import { storiesOf } from '@storybook/react';
import { withKnobs, text, boolean, number } from '@storybook/addon-knobs/react';

const stories = storiesOf('Storybook Knobs', module);

// Add the `withKnobs` decorator to add knobs support to your stories.
// You can also configure `withKnobs` as a global decorator.
stories.addDecorator(withKnobs);

// Knobs for React props
stories.add('with a button', () => (
  <button disabled={boolean('Disabled', false)} >
    {text('Label', 'Hello Button')}
  </button>
));

// Knobs as dynamic variables.
stories.add('as dynamic variables', () => {
  const name = text('Name', 'Arunoda Susiripala');
  const age = number('Age', 89);

  const content = `I am ${name} and I'm ${age} years old.`;
  return (<div>{content}</div>);
});

With Angular

import { storiesOf } from '@storybook/angular';
import { boolean, number, text, withKnobs } from '@storybook/addon-knobs/angular';

import { Button } from '@storybook/angular/demo';

const stories = storiesOf('Storybook Knobs', module);

// "withKnobs" decorator should be applied before the stories using knobs
stories.addDecorator(withKnobs);

// Knobs for Angular props
stories.add('with text', () => ({
  component: Button,
  props: {
   text: text('text', 'Hello Button'), // The first param of the knob function has to be exactly the same as the component input.
  },
}));

Categorize your knobs by assigning them a groupId. When a groupId exists, tabs will appear in the knobs storybook panel to filter between the groups. Knobs without a groupId are automatically categorized into the ALL group.

// Knob assigned a groupId.
stories.add('as dynamic variables', () => {
  const groupId = 'GROUP-ID1'
  const name = text('Name', 'Arunoda Susiripala', groupId);

  const content = `My name is ${name}.`;
  return (<div>{content}</div>);
});

In the case of Vue, use these imports:

import { storiesOf } from '@storybook/vue';
import { withKnobs, text, boolean, number } from '@storybook/addon-knobs/vue';

In the case of React-Native, use these imports:

import { storiesOf } from '@storybook/react-native';
import { withKnobs, text, boolean, number } from '@storybook/addon-knobs/react';

In the case of Angular, use these imports:

import { storiesOf } from '@storybook/angular';
import { withKnobs, text, boolean, number } from '@storybook/addon-knobs/angular';

In the case of Mithril, use these imports:

import { storiesOf } from '@storybook/mithril';
import { withKnobs, text, boolean, number } from '@storybook/addon-knobs/mithril';

You can see your Knobs in a Storybook panel as shown below.

Additional Links

Introduction blog post.
Watch this video on how to use knobs
Live Storybook with Knobs
Have a look at this sample Storybook repo.

Available Knobs

These are the knobs available for you to use. You can import these Knobs from the @storybook/addon-knobs module. Here's how to import the text Knob.

import { text } from '@storybook/addon-knobs';

Just like that, you can import any other following Knobs:

text

Allows you to get some text from the user.

import { text } from '@storybook/addon-knobs/react';

const label = 'Your Name';
const defaultValue = 'Arunoda Susiripala';
const groupId = 'GROUP-ID1';

const value = text(label, defaultValue, groupId);

boolean

Allows you to get a boolean value from the user.

import { boolean } from '@storybook/addon-knobs/react';

const label = 'Agree?';
const defaultValue = false;
const groupId = 'GROUP-ID1';

const value = boolean(label, defaultValue, groupId);

number

Allows you to get a number from the user.

import { number } from '@storybook/addon-knobs/react';

const label = 'Age';
const defaultValue = 78;
const groupId = 'GROUP-ID1';

const value = number(label, defaultValue);

For use with groupId, pass the default options as the third argument

const value = number(label, defaultValue, {}, groupId);

number bound by range

Allows you to get a number from the user using a range slider.

import { number } from '@storybook/addon-knobs/react';

const label = 'Temperature';
const defaultValue = 73;
const options = {
   range: true,
   min: 60,
   max: 90,
   step: 1,
};
const groupId = 'GROUP-ID1';

const value = number(label, defaultValue, options, groupId);

color

Allows you to get a colour from the user.

import { color } from '@storybook/addon-knobs/react';

const label = 'Color';
const defaultValue = '#ff00ff';
const groupId = 'GROUP-ID1';

const value = color(label, defaultValue, groupId);

object

Allows you to get a JSON object or array from the user.

import { object } from '@storybook/addon-knobs/react';

const label = 'Styles';
const defaultValue = {
  backgroundColor: 'red'
};
const groupId = 'GROUP-ID1';

const value = object(label, defaultValue, groupId);

Make sure to enter valid JSON syntax while editing values inside the knob.

array

Allows you to get an array of strings from the user.

import { array } from '@storybook/addon-knobs/react';

const label = 'Styles';
const defaultValue = ['Red'];
const groupId = 'GROUP-ID1';

const value = array(label, defaultValue);

While editing values inside the knob, you will need to use a separator. By default it's a comma, but this can be override by passing a separator variable.
import { array } from '@storybook/addon-knobs/react';

const label = 'Styles';
const defaultValue = ['Red'];
const separator = ':';
const value = array(label, defaultValue, separator);

For use with groupId, pass the default separator as the third argument

const value = array(label, defaultValue, ',', groupId);

select

Allows you to get a value from a select box from the user.

import { select } from '@storybook/addon-knobs/react';

const label = 'Colors';
const options = {
  red: 'Red',
  blue: 'Blue',
  yellow: 'Yellow',
};
const defaultValue = 'red';
const groupId = 'GROUP-ID1';

const value = select(label, options, defaultValue, groupId);

You can also provide options as an array like this: ['red', 'blue', 'yellow']

selectV2

In v4 this will replace select. The value from the select now uses the values from the options object.

import { selectV2 } from '@storybook/addon-knobs';

const label = 'Colors';
const options = {
  Red: 'red',
  Blue: 'blue',
  Yellow: 'yellow',
  Rainbow: ['red', 'orange', 'etc'],
  None: null,
};
const defaultValue = 'Red';
const groupId = 'GROUP-ID1';

const value = selectV2(label, options, defaultValue, groupId);

date

Allow you to get date (and time) from the user.

import { date } from '@storybook/addon-knobs/react';

const label = 'Event Date';
const defaultValue = new Date('Jan 20 2017');
const groupId = 'GROUP-ID1';

const value = date(label, defaultValue, groupId);

Note: the default value must not change - e.g., do not do date('Label', new Date()) or date('Label')

The date knob returns the selected date as stringified Unix timestamp (e.g. "1510913096516"). If your component needs the date in a different form you can wrap the date function:

function myDateKnob(name, defaultValue) {
  const stringTimestamp = date(name, defaultValue)
  return new Date(stringTimestamp)
}

button

Allows you to include a button and associated handler.

import { button } from '@storybook/addon-knobs';

const label = 'Do Something';
const handler = () => doSomething('foobar');
const groupId = 'GROUP-ID1';

button(label, handler, groupId);

withKnobs vs withKnobsOptions

If you feel like this addon is not performing well enough there is an option to use withKnobsOptions instead of withKnobs. Usage:

import { storiesOf } from '@storybook/react';

const stories = storiesOf('Storybook Knobs', module);

stories.addDecorator(withKnobsOptions({
  debounce: { wait: number, leading: boolean}, // Same as lodash debounce.
  timestamps: true // Doesn't emit events while user is typing.
}));

Typescript

If you are using typescript, make sure you have the type definitions installed for the following libs:

node
react

You can install them using npm install -save @types/node @types/react, assuming you are using Typescript >2.0.

@croquiscom/storybook-addon-knobs

Storybook Addon Knobs

Getting Started

With React

With Angular

Additional Links

Available Knobs

text

boolean

number

number bound by range

color

object

array

select

selectV2

date

button

withKnobs vs withKnobsOptions

Typescript

Readme

Keywords

Package Sidebar

Install

Repository

Homepage

Weekly Downloads

Version

License

Unpacked Size

Total Files

Last publish

Collaborators

@croquiscom/storybook-addon-knobs

Storybook Addon Knobs

Getting Started

With React

With Angular

Additional Links

Available Knobs

text

boolean

number

number bound by range

color

object

array

select

selectV2

date

button

withKnobs vs withKnobsOptions

Typescript

Readme

Keywords

Package Sidebar

Install

Repository

Homepage

DownloadsWeekly Downloads

Version

License

Unpacked Size

Total Files

Last publish

Collaborators

Weekly Downloads