gem-hunter
Language: TypeScript
Lightweight React component for animating height using CSS transitions. Slide up/down the element, and animate it to any specific height.
No dependencies React component for animating height using CSS transitions.
Slide an element up and down or animate it to any specific height.
Content's opacity can be optionally animated as well (check animateOpacity prop bellow).
CSS classes are applied in specific animation states, check animationStateClasses prop.
This is version 3.x branch, rewritten to hooks, which means you'll need React version 16.8 or newer.
For version 2.x, check v2 branch
onAnimationStart -> onHeightAnimationStartonAnimationEnd -> onHeightAnimationEndLive demo: muffinman.io/react-animate-height
Because multiple people asked how to animate list items, I created this simple example for that as well.
To build the examples locally, run:
npm install
npm start
Then open http://127.0.0.1:8000/ in your browser of choice browser.
Or play with this sandbox.
Get it from npm
$ npm install --save react-animate-height
Import and use it in your React app.
import React, { useState } from 'react'; import AnimateHeight from 'react-animate-height'; const Example = () => { const [height, setHeight] = useState(0); return ( <div> <button aria-expanded={height !== 0} aria-controls="example-panel" onClick={() => setHeight(height === 0 ? 'auto' : 0)} > {height === 0 ? 'Open' : 'Close'} </button> <AnimateHeight id="example-panel" duration={500} height={height} // see props documentation below > <h1>Your content goes here</h1> <p>Put as many React or HTML components here.</p> </AnimateHeight> </div> ); };
height: numeric or percentage value (ie. '50%') or 'auto', required
When changed, element height will be animated to that height.
To slide up use 0, for slide down use 'auto'
duration: integer, default: 500
Duration of the animation in milliseconds
delay: integer, default: 0
Animation delay in milliseconds
easing: string, default: 'ease'
CSS easing function to be applied to the animation
id: string
HTML id attribute.
className: string
CSS class to be applied to the element
Please note that you shouldn't apply properties that are messing with the layout (like display, height...), as these might break height calculations
ref: React.MutableRefObject<HTMLDivElement | null>
Reference to the main div element.
const wrapperDiv = useRef<HTMLDivElement | null>(null); <AnimateHeight ref={wrapperDiv}>
contentRef: React.MutableRefObject<HTMLDivElement | null>
Reference to the content div element.
const contentDiv = useRef<HTMLDivElement | null>(null); <AnimateHeight contentRef={contentDiv}>
style: object
CSS style object, it will be merged with inline styles of the component
Please note that you shouldn't apply properties that are messing with the layout (display, height are omitted from the type already), as these might break height calculations
contentClassName: string
CSS class to be applied to content wrapper element
Please note that you shouldn't apply properties that are messing with the layout (like display, height...), as these might break height calculations
animationStateClasses: object
Partial object containing CSS class names for animation states. It is going be to merged with the default values:
{
animating: 'rah-animating',
animatingUp: 'rah-animating--up',
animatingDown: 'rah-animating--down',
static: 'rah-static',
animatingToHeightZero: 'rah-animating--to-height-zero',
animatingToHeightAuto: 'rah-animating--to-height-auto',
animatingToHeightSpecific: 'rah-animating--to-height-specific',
staticHeightZero: 'rah-static--height-zero',
staticHeightAuto: 'rah-static--height-auto',
staticHeightSpecific: 'rah-static--height-specific',
}
Please note that this one will be merged with the default object and cached when component is created, so changing it afterwards will have no effect.
onHeightAnimationStart: function
Callback which will be called when animation starts.
This first argument passed to this callback is an object containing newHeight, the pixel value of the height at which the animation will end.
onHeightAnimationEnd: function
Callback which will be called when animation ends.
This first argument passed to this callback is an object containing newHeight, the pixel value of the height at which the animation ended.
applyInlineTransitions: boolean, default: true
If this flag is set to false only CSS classes will be applied to the element and inline
transition styles will not be present.
animateOpacity: boolean, default: false
If set to true content will fade-in (and fade-out) while height is animated.
aria-hidden: boolean
By default, library will set aria-hidden to true when height is zero. If you wish to override it, you can pass the prop yourself.
disableDisplayNone: boolean, default: false
By default, library will set display: none when height is zero. This prop allows you to disable that behavior and handle it yourself. It is useful when using auto height, check this issue for more info. Please be careful not to break accessibility when using this prop.
Additional props will be passed to the wrapper div, to make adding attrs like aria-* easier.
Library will hide the content using display: hidden when height props is 0. It will also apply aria-hidden="true" in the same case, but you can override it by passing aria-hidden prop yourself.
When using a button to toggle height, make sure you add aria-expanded and aria-controls to make everything accessible. Here's an example:
<button aria-expanded={ height !== 0 } aria-controls="example-panel" // it has to match the id passed to AnimateHeight onClick={ toggleHeight } // your click handler that toggles height // ... all other props > Toggle </button> <AnimateHeight id="example-panel"> Content </AnimateHeight>
Component checks for prefers-reduced-motion on start and disables animations if it is set to true. Please note that component doesn't listen for potential changes of prefers-reduced-motion option.
It is not built in, but you can use AnimateHeight and ResizeObserver to automatically animate height on content change. I created a small example for you here:
While it is animating, component has overflow: hidden. When the animation is finished and height is set to "auto", overflow: hidden is removed. At that moment, any margins you have on the content inside AnimateHeight will collapse, causing content to "jump". To avoid this, just use padding inside the AnimateHeight instead of margins.
If AnimateHeight is a flex child and it's parent has a fixed height, animation won't work.
To fix this, you just need to add the following CSS rule to the AnimateHeight instance.
flex-shrink: 0;
You can do it by passing a className or directly in the style prop
<AnimateHeight style={{flexShrink: 0}}>
Check the issue #89 for the example and more details.