react-tiny-crossfade

TinyCrossfade is a lightweight component for adding css transitions when replacing one component with another. Specifically, TinyCrossfade does these things:

• Measures height and applies it inline so you can add a transition
• Adds class names when children are mounting/unmounting so you can add your animation effects.

Browser support:

TinyCrossfade needs requestAnimationFrame and element.classList in order to do its thing, so make sure to add polyfills if you need to support older browsers (like IE9 and below).

Why it exists

There are a couple of other libraries like this, like react-crossfade or react-css-transition-replace. These usually use react-transition-group which is great, but in some cases it is just too big a library if you just want to do simple css stuff. TinyCrossfade is meant to be a smaller alternative and uses react-tiny-transition instead, which is a much smaller library.

Other Tiny libraries

• react-tiny-transition
• react-tiny-collapse

Install

npm install --save react-tiny-crossfade

API:

children : React element
Single React element. The element must have a key, in order for react-tiny-crossfade to tell whether to animate or not. See example below

---

component : String = "div"
Type of element used for the wrapper node

---

duration : Number = 500
The duration of your css transition (milliseconds)

---

disableInitialAnimation : Boolean = false
Disable the animation when TinyTransition mounts

---

classNames : Object =

{
	beforeEnter: "before-enter",
	entering: "entering",
	beforeLeave: "before-leave",
	leaving: "leaving"
}

Classnames to use when mounting / unmounting

---

Example usage:

import TinyCrossfade from "react-tiny-crossfade";

...

<TinyCrossfade className="component-wrapper">
  {this.state.showComponentA
  	 ? <ComponentA key="a" /> // NOTE: Key is required for animations to work
  	 : <ComponentB key="b" />
  }
</TinyCrossfade>

CSS example:

TinyCrossfade will add the following class names (unless you provided your own). When your child component is mounting, before-enter will be applied. Here's where you put the initial styles of your mounting animation. One frame later, entering will be applied, which is where you put the final animation styles as well as a transition property. Same logic for unmounting-transition.

(Remember to add transition and overflow to the wrapper if you want animated height)

.component-wrapper {
  transition: height 0.5s;
  overflow: hidden;
}

.before-enter {
  opacity: 0;
}

.entering {
  opacity: 1;
  transition: opacity 0.5s;
}

.before-leave {
  opacity: 1;
}

.leaving {
  opacity: 0;
  transition: opacity 0.5s;
}