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Spectacle

Join the chat at https://gitter.im/FormidableLabs/spectacle Travis Status ReactJS based Presentation Library

Spectacle Boilerplate

Contents

Getting Started

The new best way to get started is by running create-react-app my-presentation --scripts-version spectacle-scripts. This will use create-react-app to create almost everything you need. This however, doesn't include publish scripts, and ejecting is required for fancy stuff.

The second best way to get started is by using the Spectacle Boilerplate.

Alternatively, you can npm install spectacle and write your own build configurations. We also provide full UMD builds (with a Spectacle global variable) of the library at dist/spectacle.js and dist/spectacle.min.js for more general use cases. You could, for example, include the library via a script tag with: https://unpkg.com/spectacle@VERSION/dist/spectacle.min.js.

Note that we have webpack externals for react, react-dom, and prop-types, so you will need to provide them in your upstream build or something like linking in via script tags in your HTML page for all three libraries. This comports with our project dependencies which place these three libraries in peerDependencies.

But really, it is SO much easier to just use the boilerplate. Trust me.

One Page

To aid with speedy development / kicking the tires on spectacle, we support using a simple boilerplate HTML page with a bespoke script tag that contains your entire presentation. The rest of the setup will take care of transpiling your React/ESnext code, providing Spectacle, React, and ReactDOM libraries, and being raring to go with a minimum of effort.

We can start with this project's sample at one-page.html. It's essentially, the same presentation as the fully-built-from-source version, with a few notable exceptions:

  1. There are no imports or requires. Everything must come from the global namespace. This includes Spectacle, React, ReactDOM and all the Spectacle exports from ./src/index.js -- Deck, Slide, themes, etc.

  2. The presentation must include exactly one script tag with the type text/spectacle that is a function. Presently, that function is directly inserted inline into a wrapper code boilerplate as a React Component render function. The wrapper is transpiled. There should not be any extraneous content around it like outer variables or comments.

    Good examples:

    <script type="text/spectacle">
  () => (
    <Deck>{/* SLIDES */}</Deck>
  )
</script>
    <script type="text/spectacle">
  () => {
    // Code-y code stuff in JS...

    return (
      <Deck>{/* SLIDES */}</Deck>
    );
  }
</script>

    Bad examples of what not to do:

    <script type="text/spectacle">
  // Outer comment (BAD)
  const outerVariable = "BAD";

  () => (
    <Deck>{/* SLIDES */}</Deck>
  )
</script>

... with those guidelines in mind, here's the boilerplate that you can literally copy-and-paste into an HTML file and start a Spectacle presentation that works from the get go!

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width initial-scale=1 user-scalable=no" />
    <title>Spectacle</title>
    <link href="https://fonts.googleapis.com/css?family=Lobster+Two:400,700" rel="stylesheet" type="text/css">
    <link href="https://fonts.googleapis.com/css?family=Open+Sans+Condensed:300,700" rel="stylesheet" type="text/css">
    <link href="https://unpkg.com/normalize.css@7/normalize.css" rel="stylesheet" type="text/css">
</head>
<body>
    <div id="root"></div>
    <script src="https://unpkg.com/prop-types@15/prop-types.js"></script>
    <script src="https://unpkg.com/react@16/umd/react.production.min.js"></script>
    <script src="https://unpkg.com/react-dom@16/umd/react-dom.production.min.js"></script>
    <script src="https://unpkg.com/@babel/standalone/babel.js"></script>
    <script src="https://unpkg.com/spectacle@^4/dist/spectacle.js"></script>
    <script src="https://unpkg.com/spectacle@^4/lib/one-page.js"></script>
    <script type="text/spectacle">
      () => {
        // Your JS Code goes here

        return (
          <Deck>
          {/* Throw in some slides here! */}
          </Deck>
        );
      }
    </script>
</body>
</html>

Development

After downloading the boilerplate, your first order of business is to open terminal and run npm install

Next run rm -R .git to remove the existing version control.

Then, to start up the local server, run npm start

Open a browser and hit http://localhost:3000, and we are ready to roll

Build & Deployment

Building the dist version of the slides is as easy as running npm run build:dist

If you want to deploy the slideshow to surge, run npm run deploy

⚠️ If you are deploying the dist version to GitHub Pages, note that the built bundle uses an absolute path to the /dist/ directory while GitHub Pages requires the relative ./dist/ to find any embedded assets and/or images. A very hacky way to fix this is to edit one place in the produced bundle, as shown in this GitHub issue.

Presenting

Spectacle comes with a built in presenter mode. It shows you a slide lookahead, current time and your current slide:

http://i.imgur.com/jW8uMYY.png

Otherwise, it can also show you a stopwatch to count the elapsed time:

http://i.imgur.com/VDltgmZ.png

To present:

Note: Any windows/tabs in the same browser that are running Spectacle will sync to one another, even if you don't want to use presentation mode

Check it out:

http://i.imgur.com/H7o2qHI.gif

You can toggle the presenter or overview mode by pressing respectively alt+p and alt+o.

Controls

Key Combination Function
Right Arrow Next Slide
Left Arrow Previous Slide
Space Next Slide
Shift+Space Previous Slide
Alt/Option + O Toggle Overview Mode
Alt/Option + P Toggle Presenter Mode
Alt/Option + T Toggle Timer in Presenter Mode
Alt/Option + A Start autoplay (if enabled)

Fullscreen

Fullscreen can be toggled via browser options, or by hovering over the bottom right corner of your window until the fullscreen icon appears and clicking it.

PDF Export

Exporting a totally sweet looking PDF from your totally sweet looking Spectacle presentation is absurdly easy. You can either do this via the browser, or from the command line:

CLI

  • Run npm install spectacle-renderer -g
  • Run npm start on your project and wait for it to build and be available
  • Run spectacle-renderer
  • A totally cool PDF is created in your project directory

For more options and configuration of this tool, check out:

https://github.com/FormidableLabs/spectacle-renderer

Browser

  • Run npm start
  • Open http://localhost:3000/
  • Add export& after the ? on the URL of page you are redirected to, e.g.: http://localhost:3000/#/?export&_k=wbyhif
  • Bring up the print dialog (ctrl or cmd + p)
  • Check "Background Graphics" to on if you are about that life
  • Change destination to "Save as PDF", as shown below:

http://i.imgur.com/t6GL5Oc.png

If you want to print your slides, and want a printer friendly version, simply repeat the above process but instead print from http://localhost:3000/?export&print

Basic Concepts

Main file

Your presentation files & assets will live in the presentation folder.

The main .js file you write your deck in is /presentation/index.js

Check it out here in the boilerplate.

// index.js

import React, { Component } from 'react';
import {
  Appear, BlockQuote, Cite, CodePane, Code, Deck, Fill, Fit,
  Heading, Image, Layout, ListItem, List, Quote, Slide, Text
} from 'spectacle';

export default class extends Component {
  render() {
    return (
      <Deck>
        <Slide>
          <Text>Hello</Text>
        </Slide>
      </Deck>
    );
  }
}

Here is where you can use the library's tags to compose your presentation. While you can use any JSX syntax here, building your presentation with the supplied tags allows for theming to work properly.

The bare minimum you need to start is a Deck element and a Slide element. Each Slide element represents a slide inside of your slideshow.

Themes

In Spectacle, themes are functions that return style objects for screen & print.

You can import the default theme from:

import createTheme from "spectacle/lib/themes/default";

Or create your own based upon the source.

index.js is what you would edit in order to create a custom theme of your own, using object based styles.

You will want to edit index.html to include any web fonts or additional CSS that your theme requires.

createTheme(colors, fonts)

Spectacle's functional theme system allows you to pass in color and font variables that you can use on your elements. The fonts configuration object can take a string for a system font or an object that specifies it‘s a Google Font. If you use a Google Font you can provide a styles array for loading different weights and variations. Google Font tags will be automatically created. See the example below:

const theme = createTheme({
  primary: "red",
  secondary: "blue"
}, {
  primary: "Helvetica",
  secondary: { name: "Droid Serif", googleFont: true, styles: [ "400", "700i" ] }
});

The returned theme object can then be passed to the Deck tag via the theme prop, and will override the default styles.

FAQ

How can I easily style the base components for my presentation?

Historically, custom styling in Spectacle has meant screwing with a theme file, or using gross !important overrides. We fixed that. Spectacle is now driven by emotion, so you can bring your own styling library, whether its emotion itself, or something like styled-components or glamorous. For example, if you want to create a custom Heading style:

import styled from 'react-emotion';
import { Heading } from 'spectacle';

const CustomHeading = styled(Heading)`
  font-size: 1.2em;
  color: papayawhip;
`;

How can I separate my slides into other files?

Until this release, you would have to do some array shenanigans, but now you can just wrap those slides with an element that has a special prop:

// mySlides.js
export default class mySlides extends Component {
  render() {
    return (
      <div hasSlideChildren>
        <Slide>1</Slide>
        <Slide>2</Slide>
        <Slide>3</Slide>
      </div>
    )
  }
}

Tag API

In Spectacle, presentations are composed of a set of base tags. We can separate these into three categories: Main tags, Layout tags & Element tags.

Main Tags

Deck

The Deck tag is the root level tag for your presentation. It supports the following props:

Name PropType Description
controls PropTypes.bool Show control arrows when not in fullscreen
contentHeight PropTypes.numbers Baseline content area height (default: 700)
contentWidth PropTypes.numbers Baseline content area width (default: 1000)
history PropTypes.object Accepts custom configuration for history
progress PropTypes.string Accepts pacman, bar, number or none. To override the color, change the 'quarternary' color in the theme.
theme PropTypes.object Accepts a theme object for styling your presentation
transition PropTypes.array Accepts slide, zoom, fade or spin, and can be combined. Sets global slide transitions. Note: If you use the 'scale' transition, fitted text won't work in Safari.
transitionDuration PropTypes.number Accepts integer value in milliseconds for global transition duration.
autoplay PropTypes.bool Automatically advance slides.
autoplayDuration PropTypes.number Accepts integer value in milliseconds for global autoplay duration, defaults to 7000.

Slide (Base)

The slide tag represents each slide in the presentation. Giving a slide tag an id attribute will replace its number based navigation hash with the id provided. It supports the following props, in addition to any of the props outlined in the Base class props listing:

Name PropType Description
align PropTypes.string Accepts a space delimited value for positioning interior content. The first value can be flex-start (left), center (middle), or flex-end (right). The second value can be flex-start (top) , center (middle), or flex-end (bottom). You would provide this prop like align="center center", which is its default.
controlColor PropTypes.string Used to override color of control arrows on a per slide basis, accepts color aliases, or valid color values.
goTo PropTypes.number Used to navigate to a slide for out-of-order presenting. Slide numbers start at 1. This can also be used to skip slides as well.
id PropTypes.string Used to create a string based hash.
maxHeight PropTypes.number Used to set max dimensions of the Slide.
maxWidth PropTypes.number Used to set max dimensions of the Slide.
notes PropTypes.string Text which will appear in the presenter mode. Can be HTML.
onActive PropTypes.func Optional function that is called with the slide index when the slide comes into view.
progressColor PropTypes.string Used to override color of progress elements on a per slide basis, accepts color aliases, or valid color values.
transition PropTypes.array Accepts slide, zoom, fade, spin, or a function, and can be combined. Sets the slide transition. This will affect both enter and exit transitions. Note: If you use the 'scale' transition, fitted text won't work in Safari.
transitionIn PropTypes.array Specifies the slide transition when the slide comes into view. Accepts the same values as transition.
transitionOut PropTypes.array Specifies the slide transition when the slide exits. Accepts the same values as transition.
transitionDuration PropTypes.number Accepts integer value in milliseconds for slide transition duration.

Wrapping Slides

If you author your slides in another file or want any kind of grouping that requires one additional level of nesting, you can add a hasSlideChildren prop to their parent element. This lets Spectacle identify that it is a wrapper, and will disregard the heirarchy instead opting to read the child slides as if the wrapper was not present.

Transition Function

Spectacle now supports defining custom transitions. The function prototype is (transitioning: boolean, forward: boolean) => Object. The transitioning param is true when the slide enters and exits. The forward param is true when the slide is entering, false when the slide is exiting. The function returns a style object. You can mix string-based transitions and functions. Styles provided when transitioning is false will appear during the lifecyle of the slide. An example is shown below:

<Slide
  transition={[
    'fade',
    (transitioning, forward) => {
      const angle = forward ? -180 : 180;
      return {
        transform: `
          translate3d(0%, ${transitioning ? 100 : 0}%, 0)
          rotate(${transitioning ? angle : 0}deg)
        `,
        backgroundColor: transitioning ? '#26afff' : '#000'
      };
    }
  ]}
>

Notes

The notes tag allows to use any tree of react elements as the notes of a slide. It is used as a child node of a slide tag and its children override any value given as the notes attribute of its parent slide.

<Slide ...>
  <Notes>
    <h4>Slide notes</h4>
    <ol>
      <li>First note</li>
      <li>Second note</li>
    </ol>
  </Notes>
  {/* Slide content */}
</Slide>

MarkdownSlides

The MarkdownSlides function lets you create a single or multiple slides using Markdown. It can be used as a tagged template literal or a function. Three dashes (---) are used as a delimiter between slides.

Tagged Template Literal Usage

<Deck ...>
  {MarkdownSlides`
## Slide One Title
Slide Content
---
## Slide Two Title
Slide Content
  `}
</Deck>

Function Usage

import slidesMarkdown from "raw-loader!markdown.md";

<Deck ...>
  {MarkdownSlides(slidesMarkdown)}
</Deck>

Layout Tags

Layout tags are used for layout using Flexbox within your slide. They are Layout, Fit & Fill.

Layout

The layout tag is used to wrap Fit and Fill tags to provide a row.

Fit

The fit tag only takes up as much space as its bounds provide.

Fill

The fill tag takes up all the space available to it. For example, if you have a Fill tag next to a Fit tag, the Fill tag will take up the rest of the space. Adjacent Fill tags split the difference and form an equidistant grid.

Markdown Tag

Markdown (Base)

The Markdown tag is used to add inline markdown to your slide. You can provide markdown source via the source prop, or as children. You can also provide a custom mdast configuration via the mdastConfig prop.

Markdown generated tags aren't prop configurable, and instead render with your theme defaults.

Name PropType Description
source PropTypes.string Markdown source

Magic Tag

Magic

NOTE: The Magic tag uses the Web Animations API. If you use the Magic tag and want it to work places other than Chrome, you will need to include the polyfill https://github.com/web-animations/web-animations-js

The Magic Tag is a new experimental feature that attempts to recreate Magic Move behavior that slide authors might be accustomed to coming from Keynote. It wraps slides, and transitions between positional values for child elements. This means that if you have two similar strings, we will transition common characters to their new positions. This does not transition on non positional values such as slide background color or font size. Do not use a transition prop on your slides if you are wrapping them with a Magic tag since it will take care of the transition for you.

Using Magic is pretty simple, you just wrap your slides with it, and it transitions between them:

<Magic>
  <Slide><Heading>First Heading</Heading></Slide>
  <Slide><Heading>Second Heading</Heading></Slide>
</Magic>

Transitioning between similar states will vary based upon the input content. It will look better when there are more common elements. An upcoming patch will allow for custom keys, which will provide greater control over which elements are identified as common for reuse.

Until then, feedback is very welcome, as this is a non-trivial feature and we anticipate iterating on the behind the scenes mechanics of how it works, so that we can accommodate most use cases.

Element Tags

The element tags are the bread and butter of your slide content. Most of these tags derive their props from the Base class, but the ones that have special options will have them listed:

Appear

This tag does not extend from Base. It's special. Wrapping elements in the appear tag makes them appear/disappear in order in response to navigation.

For best performance, wrap the contents of this tag in a native DOM element like a <div> or <span>.

Name PropType Description
order PropTypes.number An optional integer starting at 1 for the presentation order of the Appear tags within a slide. If a slide contains ordered and unordered Appear tags, the unordered will show first.
transitionDuration PropTypes.number An optional duration (in milliseconds) for the Appear animation. Default value is 300.
startValue Proptypes.object An optional style object that defines the starting, inactive state of the Appear tag. The default animation is a simple fade-in, so the default startValue value is { opacity: 0 }.
endValue Proptypes.object An optional style object that defines the ending, active state of the Appear tag. The default animation is a simple fade-in, so the default endValue value is { opacity: 1 }.
easing PropTypes.string An optional victory easing curve for the Appear animation. The various options are documented in the Victory Animation easing docs. Default value is quadInOut

Anim

If you want extra flexibility with animated animation, you can use the Anim component instead of Appear. It will let you have multi-step animations for each individual fragment. You can use this to create fancy animated intros, in-slide carousels, and many other fancy things. This tag does not extend from Base. It's special.

For best performance, wrap the contents of this tag in a native DOM element like a <div> or <span>.

Name PropType Description
order PropTypes.number An optional integer starting at 1 for the presentation order of the Appear tags within a slide. If a slide contains ordered and unordered Appear tags, the unordered will show first.
transitionDuration PropTypes.number A duration (in milliseconds) for the animation. Default value is 300.
fromStyle Proptypes.object A style object that defines the starting, inactive state of the Anim tag.
toStyle Proptypes.array An array of style objects that define each step in the animation. They will step from one toStyle object to another, until that fragment is finished with its animations.
easing PropTypes.string A victory easing curve for the Appear animation. The various options are documented in the Victory Animation easing docs.
onAnim PropTypes.fun This function is called every time the Anim component plays an animation. It'll be called with two arguments, forwards, a boolean indicating if it was stepped forwards or backwards, and the index of the animation that was just played.

BlockQuote, Quote and Cite (Base)

These tags create a styled blockquote. Use them as follows:

<BlockQuote>
  <Quote>Ken Wheeler is amazing</Quote>
  <Cite>Everyone</Cite>
</BlockQuote>

CodePane (Base)

This tag displays a styled, highlighted code preview. I prefer putting my code samples in external .example files and requiring them using raw-loader as shown in the demo. Here are the props:

Name PropType Description
lang PropTypes.string Prism compatible language name. i.e: 'javascript'
source PropTypes.string String of code to be shown
className PropTypes.string String of a className to be appended to the CodePane
theme PropTypes.string Accepts light, dark, or external for the source editor's syntax highlighting. Defaults to dark.

If you want to change the theme used here, you can include a prism theme in index.html via a style or a link tag. For your theme to be actually applied correctly you need to set the theme prop to "external", which disables our builtin light and dark themes. Please note that including a theme can actually influence all CodePane and Playground components, even if you don't set this prop, since some Prism themes use very generic CSS selectors.

CodePane and Playground both use the prism library under the hood, which has several themes that are available to include.

Code (Base)

A simple tag for wrapping inline text that you want lightly styled in a monospace font.

Component Playground

This tag displays a two-pane view with a ES6 source code editor on the right and a preview pane on the left for showing off custom React components. React and render are supplied as variables. To render a component call render with some JSX code. Any console output will be forwarded to the main console in the browser.

For more information on the playground read the docs over at react-live.

Name PropType Description
code PropTypes.string The code block you want to initially supply to the component playground. If none is supplied a demo component will be displayed.
previewBackgroundColor PropTypes.string The background color you want for the preview pane. Defaults to #fff.
theme PropTypes.string Accepts light, dark, or external for the source editor's syntax highlighting. Defaults to dark.
scope PropTypes.object Defines any outside modules or components to expose to the playground. React, Component, and render are supplied for you.

Example code blocks:

const Button = ({ title }) => (<button type="button">{ title }</button>);
render(<Button title="My Button" />);
class View extends React.Component {
  componentDidMount() {
    console.log("Hello");
  }

  render() {
    return (<div>My View</div>);
  }
}
render(<View />);

If you want to change the theme used here, please refer to the instructions above in the CodePane's API reference.

Go To Action (Base)

The GoToAction tag lets you jump to another slide in your deck. The GoToAction can be used a simple button that supports Base styling or accept a render prop with a callback to support custom components.

Name PropType Description
slide PropTypes.string or PropTypes.number The string identifier or number of the side the button should jump to. Slide numbers start at 1. This is only used in the simple button configuration.
render PropTypes.func A function with a goToSlide param that should return a React element to render. This is only used in the custom component configuration.
Simple Button Configuration Example
<GoToAction slide={3}>Jump to 3</GoToAction>
Custom Component Configuration Example
<GoToAction
  render={goToSlide => (
    <CustomComponent onClick={() => goToSlide("wait-wut")}>
      WAIT WUT!?
    </CustomComponent>
  )}
/>

Heading (Base)

Heading tags are special in that, when you specify a size prop, they generate the appropriate heading tag, and extend themselves with a style that is defined in the theme file for that heading. Line height can be adjusted via a numeric lineHeight prop.

Name PropType Description
fit PropTypes.boolean When set to true, fits text to the slide's width. Note: If you use the 'scale' transition, this won't work in Safari.
lineHeight PropTypes.number Sets the line height of your text.

Image (Base)

Name PropType Description
alt PropTypes.string Set the alt property of the image
display PropTypes.string Set the display style property of the image
height PropTypes.string or PropTypes.number Supply a height to the image
src PropTypes.string Image src
width PropTypes.string or PropTypes.number Supply a width to the image

Link (Base)

The link tag is used to render <a> tags. It accepts an href prop:

Name PropType Description
href PropTypes.string String of url for href attribute
target PropTypes.string Set the target attribute

List & ListItem (Base)

Name PropType Description
ordered PropTypes.bool Render as <ol>-tag
reversed PropTypes.bool Set the reversed attribute
start PropTypes.bool Set the start attribute, Default: 1
type PropTypes.bool Set the type attribute. Default: "1"

These tags create lists. Use them as follows:

Ordered lists:

<List ordered start={2} type="A">
  <ListItem>Item 1</ListItem>
  <ListItem>Item 2</ListItem>
  <ListItem>Item 3</ListItem>
  <ListItem>Item 4</ListItem>
</List>

Unordered lists:

<List>
  <ListItem>Item 1</ListItem>
  <ListItem>Item 2</ListItem>
  <ListItem>Item 3</ListItem>
  <ListItem>Item 4</ListItem>
</List>

S (Base)

The S tag is used to add styling to a piece of text, such as underline or strikethrough.

Name PropType Description
type PropTypes.string Accepts strikethrough, underline, bold or italic

Table, TableRow, TableHeaderItem and TableItem (Base)

The Table tag is used to add table to your slide. It is used with TableHeader, TableBody, TableRow, TableHeaderItem and TableItem. Use them as follows:

<Table>
  <TableHeader>
    <TableRow>
      <TableHeaderItem></TableHeaderItem>
      <TableHeaderItem>2011</TableHeaderItem>
    </TableRow>
  </TableHeader>
  <TableBody>
    <TableRow>
      <TableItem>None</TableItem>
      <TableItem>61.8%</TableItem>
    </TableRow>
    <TableRow>
      <TableItem>jQuery</TableItem>
      <TableItem>28.3%</TableItem>
    </TableRow>
  </TableBody>
</Table>

Text (Base)

The Text tag is used to add text to your slide. Line height can be adjusted via a numeric lineHeight prop.

Name PropType Description
fit PropTypes.boolean When set to true, fits text to the slide's width. Note: If you use the 'scale' transition, this won't work in Safari.
lineHeight PropTypes.number Sets the line height of your text.

Base Props

Every component above that has (Base) after it has been extended from a common class that includes the following props:

Name PropType Description
italic PropTypes.boolean Set fontStyle to italic
bold PropTypes.boolean Set fontWeight to bold
caps PropTypes.boolean Set textTransform to uppercase
margin PropTypes.number or string Set margin value
padding PropTypes.number or string Set padding value
textColor PropTypes.string Set color value
textFont PropTypes.string Set fontFamily value
textSize PropTypes.string Set fontSize value
textAlign PropTypes.string Set textAlign value
textFont PropTypes.string Set textFont value
bgColor PropTypes.string Set backgroundColor value
bgImage PropTypes.string Set backgroundImage value
bgSize PropTypes.string Set backgroundSize value
bgPosition PropTypes.string Set backgroundPosition value
bgRepeat PropTypes.string Set backgroundRepeat value
bgDarken PropTypes.number Float value from 0.0 to 1.0 specifying how much to darken the bgImage image
overflow PropTypes.string Set overflow value
height PropTypes.string Set height value

Typeface

The Typeface tag is used to apply a specific font to text content. It can either use a font that exists on the system or load a font from the Google Fonts library. Typeface requires either font or googleFont to be defined.

Name PropType Description
font PropTypes.string Use a font from the local system
googleFont PropTypes.string Use a font from the Google Fonts library
weight PropTypes.number Numeric weight value for the font. Default: 400.
italic PropTypes.boolean Use an italics variant of the font if it exists. Default: false. 
<Typeface googleFont="Roboto Slab" weight={600}>
  <Text>This text is using bold Roboto Slab from Google Fonts.</Text>
</Typeface>
<Typeface font="SF Text" weight={400} italic={true}>
  <Text>This text is using the San Francisco Text font from the system.</Text>
</Typeface>

Third Party Extensions