viewport

Viewport

State containers which provide an interface for listening and responding to window events in a scalable fashion.

Installation

yarn add @render-props/viewport or npm i @render-props/viewport

Contents

• Viewport
  • Component which provides context from ViewportOrientation, and ViewportScroll
• ViewportProvider
  • A top-level Viewport component which stores the viewport state and provides it as context to ViewportConsumer components.
• ViewportConsumer
  • Receives context updates from ViewportProvider when the viewport state changes
• ViewportOrientation
  • Provides context for {width, height, aspect, orientation, screenOrientation} while receiving {width, height, aspect} from ViewportSize parent.
  • Updates each time the window size or orientation changes.
• ViewportSize
  • Provides context for {width, height, aspect}.
  • Updates each time the window size or orientation changes.
• ViewportQueries
  • Provides context for {inView, inViewX, inViewY, inFullView, inFullViewX, inFullViewY}
• ViewportScroll
  • Provides context for {scrollX, scrollY, scrollTo, distance, direction}
  • Updates each time the scroll position changes

---

Viewport

God component which provides context from ViewportOrientation, and ViewportScroll

Usage

import Viewport from '@render-props/viewport'

const ViewportLogger = props => {
  return (
    <Viewport>
      {({
        width,
        height,
        aspect,
        orientation,
        screenOrientation,
        scrollX,
        scrollY,
        distance,
        direction,
        scrollTo
      }) => (
        <>
          <div>
            width: {width}
          </div>
          <div>
            scrollY: {scrollY}
          </div>
          <div>
            aspect: {aspect}
          </div>
        </>
      )}
    </Viewport>
  )
}

---

Props

This component takes no props

Render Props

Methods

• scrollTo (x <integer>, [y <integer>], [options <object{duration <ms>, timing <function>}>])
  • scrolls to the provided x, y coordinates in the window. You can optionally animate this by providing an options object with a duration. By default the timing function is linear, but you could for example use this bezier-easing library: https://github.com/gre/bezier-easing

    const bezierCurve = BezierEasing(0, 0, 1, 0.5);
    scrollTo(0, 250, {timing: bezierCurve})
    
    const cubicIn = x => x * x * x
    scrollTo(0, 250, {timing: cubicIn, duration: 400})

State

Note: these are only provided if withCoords is true.

• scrollX {integer}
  • the current horizontal scroll position in px
• scrollY {integer}
  • the current vertical scroll position in px
• direction {object {x <integer>, y <integer>}}
  • the direction the window was just scrolled
    • 1 = right for x, down for y
    • -1 = left for x, up for y
    • 0 = had no direction
• distance {object {x <integer>, y <integer>}}
  • the distance between the latest recorded scroll activity in the window and the previous scroll activity
• width {integer}
  • the clientWidth of the documentElement
• height {integer}
  • the clientHeight of the documentElement
• aspect {float}
  • the aspect ratio (width / height = aspect)
• orientation {landscape|square|portrait}
  • returns landscape when width > height, square when width == height, and portrait when width < height
• screenOrientation {null|landscape-primary|landscape-secondary|portrait-primary|portrait-secondary}
  • null: when orientation.type is unavailable
  • 'landscape-primary': when the device is landscape oriented, e.g. a laptop and width > height
  • 'landscape-secondary': when the device is portrait oriented, e.g. a phone and width > height
  • 'portrait-primary': when the device is portrait oriented, e.g. a phone and width < height
  • 'portrait-secondary': when the device is landscape oriented, e.g. a laptop and width < height

---

ViewportProvider

A top-level Viewport component which stores the viewport state and provides it as context to ViewportConsumer components. It is in the only component in this package that is a not a render-prop component. It takes valid react elements as children.

There are several benefits to using the ViewportProvider/ViewportConsumer components rather than Viewport alone. There is only one event listener of each type in the Provider model - so O(1) state is being throttled and consumed vs. O(n).

Usage

import {ViewportProvider} from '@render-props/viewport'


function AppViewportProvider (AppWithViewportConsumers) {
  return (
    <ViewportProvider>
      {AppWithViewportConsumers}
    </ViewportProvider>
  )
}

---

Props

• withCoords {bool} {default: true}: if false, the component will provide getScroll, getSize, and getAspect functions as opposed to {scrollX, scrollY, width, height, aspect}

---

ViewportConsumer

Receives context updates from ViewportProvider when the viewport state changes. You can configure this component to only listen to size or scroll events by using the observe propert. See below for more details.

Usage

import {ViewportConsumer, observe} from '@render-props/viewport'


function SomeComponent (props) {
  // This consumer listens to all changes in the viewport
  return (
    <ViewportConsumer>
      {({
        width,
        height,
        aspect,
        orientation,
        screenOrientation,
        scrollX,
        scrollY,
        scrollTo
      }) => (
        <div>
          width: {width}
        </div>
      )}
    </ViewportConsumer>
  )
}

function ScrollingComponent (props) {
  // This consumer only listens to changes in viewport scroll position
  return (
    <ViewportConsumer observe='scroll'>
      {({scrollX}) => (
        <div>
          scrollX: {scrollX}
        </div>
      )}
    </ViewportConsumer>
  )
}

function SizeComponent (props) {
  // This consumer only listens to size changes in the viewport
  return (
    <ViewportConsumer observe='size'>
      {({width, height}) => (
        <div>
          width: {width}
        </div>
      )}
    </ViewportConsumer>
  )
}

---

Props

• observe {string|array<string>}
  • Configures the consumer to only update on changes to size or scroll position. By default this consumer listens to all updates.

      import {ViewportConsumer} from '@render-props/viewport'
    
      /**
       * observe.scrollX: 0b0001,
       * observe.scrollY: 0b0010,
       * observe.scroll: 0b0011,
       * observe.width: 0b0100,
       * observe.height: 0b1000,
       * observe.size: 0b1100,
       * observe.any: 0b1111,
       */
    
      // listens to scroll position changes
      <ViewportConsumer observe='scroll'/>
      // listens to width and scrollY changes
      <ViewportConsumer observe={['width', 'scrollY']}/>
      // listens to all changes
      <ViewportConsumer/>

Also see Viewport props

Render Props

See Viewport render props

---

ViewportOrientation

• Provides context for {width, height, aspect, orientation, screenOrientation} while receiving {width, height, aspect} from ViewportSize parent.
• Updates each time the window size or orientation changes.

Usage

import {ViewportOrientation} from '@render-props/viewport'

function ViewportOrientationState (props) {
  return (
    <ViewportOrientation>
      {({
        width,
        height,
        aspect,
        orientation,
        screenOrientation
      }) => (
        <div>
          orientation: {orientation}
        </div>
      )}
    </ViewportOrientation>
  )
}

---

Props

• withCoords {bool} {default: true}: if false, the component will provide getSize, and getAspect functions as opposed to {width, height, aspect}

Render Props

State

• width {integer}
  • the clientWidth of the documentElement
• height {integer}
  • the clientHeight of the documentElement
• aspect {float}
  • the aspect ratio (width / height = aspect)
• orientation {landscape|square|portrait}
  • returns landscape when width > height, square when width == height, and portrait when width < height
• screenOrientation {null|landscape-primary|landscape-secondary|portrait-primary|portrait-secondary}
  • returns null if orientation.type is unavailable
    • landscape-primary: when the device is landscape oriented, e.g. a laptop and width > height
    • landscape-secondary: when the device is portrait oriented, e.g. a phone and width > height
    • portrait-primary: when the device is portrait oriented, e.g. a phone and width < height
    • portrait-secondary: when the device is landscape oriented, e.g. a laptop and width < height

---

ViewportSize

• Provides context for {width, height, aspect}.
• Updates each time the window size or orientation changes.

Usage

import {ViewportSize} from '@render-props/viewport'

function ViewportSizeState (props) {
  return (
    <ViewportSize>
      {({width, height, aspect}) => (
        <div>
          width: {width}
        </div>
      )}
    </ViewportSize>
  )
}

---

Props

• withCoords {bool} {default: true}: if false, the component will provide getSize, and getAspect functions as opposed to {width, height, aspect}

Render Props

State

• width {integer}
  • the clientWidth of the documentElement
• height {integer}
  • the clientHeight of the documentElement
• aspect {float}
  • the aspect ratio (width / height = aspect)

---

ViewportQueries

Provides context for {inView, inViewX, inViewY, inFullView, inFullViewX, inFullViewY}

Usage

import {ViewportQueries} from '@render-props/viewport'

function ViewportQueriesState (props) {
  return (
    <ViewportQueries>
      {({width, height, aspect}) => (
        <div>
          width: {width}
        </div>
      )}
    </ViewportQueries>
  )
}

---

Render Props

Methods

• inView (element <DOMNode>, leeway <number|object{top, right, bottom, left}>)
  • returns true if @element is partially or completely visible within the window bounds, give or take @leeway
• inViewX (element <DOMNode>, leeway <number|object{top, right, bottom, left}>)
  • returns true if @element is partially or completely visible horizontally within the window bounds, give or take @leeway
• inViewY (element <DOMNode>, leeway <number|object{top, right, bottom, left}>)
  • returns true if @element is partially or completely visible vertically within the window bounds, give or take @leeway
• inFullView (element <DOMNode>, leeway <number|object{top, right, bottom, left}>)
  • returns true if @element is completely visible within the window bounds, give or take @leeway
• inFullViewX (element <DOMNode>, leeway <number|object{top, right, bottom, left}>)
  • returns true if @element is completely visible horizontally within the window bounds, give or take @leeway
• inFullViewY (element <DOMNode>, leeway <number|object{top, right, bottom, left}>)
  • returns true if @element is completely visible vertically within the window bounds, give or take @leeway

---

ViewportScroll

• Provides context for {scrollX, scrollY, scrollTo}
• Updates each time the scroll position changes

Usage

import {ViewportScroll} from '@render-props/viewport'

function ViewportScrollState (props) {
  return (
    <ViewportScroll>
      {({scrollX, scrollY, scrollTo, direction, distance}) => (
        <div>
          scrollY: {scrollY}
        </div>
      )}
    </ViewportScroll>
  )
}

---

Props

• withCoords {bool} {default: true}: if false, the component will provide a getScroll function as opposed to {scrollX, scrollY, width, height, aspect}

Render Props

Methods

• scrollTo (x <integer>, [y <integer>], [options <object{duration <ms>, timing <function>}>])
  • scrolls to the provided x, y coordinates in the window. You can optionally animate this by providing an options object with a duration. By default the timing function is linear, but you could for example use this bezier-easing library: https://github.com/gre/bezier-easing

    const bezierCurve = BezierEasing(0, 0, 1, 0.5);
    scrollTo(0, 250, {timing: bezierCurve})
    
    const cubicIn = x => x * x * x
    scrollTo(0, 250, {timing: cubicIn, duration: 400})

State

Note: these are only provided if withCoords is true.

• scrollX {integer}
  • the current horizontal scroll position in px
• scrollY {integer}
  • the current vertical scroll position in px
• direction {object {x <integer>, y <integer>}}
  • the direction the window was just scrolled
    • 1 = right for x, down for y
    • -1 = left for x, up for y
    • 0 = had no direction
• distance {object {x <integer>, y <integer>}}
  • the distance between the latest recorded scroll activity in the window and the previous scroll activity