Animation

Animate elements declaratively with nearly 100 baked‐in presets, or roll your own with custom keyframes. These animations are powered by the Web Animations API.

To animate an element, wrap it in a <pc-animation> element and set an an animation name. The animation will not start until you add the play attribute. Refer to the properties table for a list of all animation options.

<div class="animation-overview">
  <pc-animation name="bounce" duration="2000" play>
      <div class="box"></div>
  </pc-animation>
  <pc-animation name="jello" duration="2000" play>
      <div class="box"></div>
  </pc-animation>
  <pc-animation name="heartBeat" duration="2000" play>
      <div class="box"></div>
  </pc-animation>
  <pc-animation name="flip" duration="2000" play>
      <div class="box"></div>
  </pc-animation>
</div>

<style>
  .animation-overview .box {
      display: inline-block;
      width: 100px;
      height: 100px;
      margin: 1.5rem;
      background-color: var(--pc-color-primary-400);
      border-radius: var(--pc-border-radius-l);
  }
</style>

Code

The animation will only be applied to the first child element found in <pc-animation>.

Demos

Animations and easings

This demo demonstrates all of the baked‐in animations and easings. Animations are based on those found in the popular Animate.css library.

<div class="animation-sandbox">
  <pc-animation name="bounce" easing="ease-in-out" duration="2000" play>
      <div class="box"></div>
  </pc-animation>

  <div class="controls">
      <pc-select label="Animation" value="bounce"></pc-select>
      <pc-select label="Easing" value="linear"></pc-select>
      <pc-input
          type="number"
          label="Playback rate"
          min="0"
          max="2"
          step="0.25"
          value="1"
      ></pc-input>
  </div>
</div>

<script type="module">
  import { getAnimationNames, getEasingNames } from "https://cdn.jsdelivr.net/npm/placer-toolkit@0.5.1/dist/utilities/animation.js";

  const container = document.querySelector(".animation-sandbox");
  const animation = container.querySelector("pc-animation");
  const animationName = container.querySelector(".controls pc-select:nth-child(1)");
  const easingName = container.querySelector(".controls pc-select:nth-child(2)");
  const playbackRate = container.querySelector('pc-input[type="number"]');
  const animations = getAnimationNames();
  const easings = getEasingNames();

  animations.map((name) => {
      const option = Object.assign(document.createElement("pc-option"), {
          textContent: name,
          value: name
      });
      animationName.appendChild(option);
  });

  easings.map((name) => {
      const option = Object.assign(document.createElement("pc-option"), {
          textContent: name,
          value: name
      });
      easingName.appendChild(option);
  });

  animationName.addEventListener("pc-change", () => (animation.name = animationName.value));
  easingName.addEventListener("pc-change", () => (animation.easing = easingName.value));
  playbackRate.addEventListener("pc-input", () => (animation.playbackRate = playbackRate.value));
</script>

<style>
  .animation-sandbox .box {
      width: 100px;
      height: 100px;
      background-color: var(--pc-color-primary-400);
      border-radius: var(--pc-border-radius-l);
  }

  .animation-sandbox .controls {
      max-width: 300px;
      margin-top: 2rem;
  }

  .animation-sandbox .controls pc-select {
      margin-bottom: 1rem;
  }
</style>

Code

Intersection Observer

Use an Intersection Observer to control the animation when an element enters or exits the viewport. For example, scroll the box below in and out of your screen. The animation stops when the box exits the viewport and restarts each time it enters the viewport.

<div class="animation-scroll">
  <pc-animation
      name="jackInTheBox"
      duration="2000"
      iterations="1"
  >
      <div class="box"></div>
  </pc-animation>
</div>

<script>
  const container = document.querySelector(".animation-scroll");
  const animation = container.querySelector("pc-animation");
  const box = animation.querySelector(".box");

  const observer = new IntersectionObserver((entries) => {
      if (entries[0].isIntersecting) {
          animation.play = true;
      } else {
          animation.play = false;
          animation.currentTime = 0;
      }
  });

  observer.observe(box);
</script>

<style>
  .animation-scroll .box {
      display: inline-block;
      width: 100px;
      height: 100px;
      background-color: var(--pc-color-primary-400);
      border-radius: var(--pc-border-radius-l);
  }
</style>

Code

Custom keyframes

Supply your own keyframes to build custom animations.

<div class="animation-keyframes">
  <pc-animation easing="ease-in-out" duration="2000" play>
      <div class="box"></div>
  </pc-animation>
</div>

<script>
  const animation = document.querySelector(".animation-keyframes pc-animation");

  animation.keyframes = [
      {
          offset: 0,
          easing: "cubic-bezier(0.250, 0.460, 0.450, 0.940)",
          fillMode: "both",
          transformOrigin: "center center",
          transform: "rotate(0deg)",
      },
      {
          offset: 1,
          easing: "cubic-bezier(0.250, 0.460, 0.450, 0.940)",
          fillMode: "both",
          transformOrigin: "center center",
          transform: "rotate(90deg)",
      },
  ];
</script>

<style>
  .animation-keyframes .box {
      width: 100px;
      height: 100px;
      background-color: var(--pc-color-primary-400);
      border-radius: var(--pc-border-radius-l);
  }
</style>

Code

Playing animations programmatically

Animations won’t play until you add the play attribute. You can omit it initially, then apply it programmatically such as after a user interaction. In this demo, the button will animate once every time the button is clicked.

<div class="animation-form">
  <pc-animation name="rubberBand" duration="1000" iterations="1">
      <pc-button appearance="primary">Click me</pc-button>
  </pc-animation>
</div>

<script>
  const container = document.querySelector(".animation-form");
  const animation = container.querySelector("pc-animation");
  const button = container.querySelector("pc-button");

  button.addEventListener("click", () => {
      animation.play = true;
  });
</script>

Code

Properties

Name	Description	Default
`name`	The name of the built‐in animation to use. For custom animations, use the `keyframes` prop. `string`	`"none"`
`play`	Plays the animation. When omitted, the animation will be paused. This attribute will be automatically removed when the animation finishes or gets cancelled. `boolean`	`false`
`delay`	The number of milliseconds to delay the start of the animation. `number`	`0`
`direction`	Determines the direction of playback as well as the behaviour when reaching the end of an iteration. Learn more about the CSS <code>animation-direction</code> property. `PlaybackDirection`	`"normal"`
`duration`	The number of milliseconds each iteration of the animation takes to complete. `number`	`1000`
`easing`	The easing function to use for the animation. This can be an easing function name like `easeInSine` or a custom easing function like `cubic-bezier(0.12, 0, 0.39, 0)`. `string`	`"ease-in-out"`
`endDelay` `end-delay`	The number of milliseconds to delay after the active period of an animation sequence. `number`	`0`
`fill`	Sets how the animation applies styles to its target before and after its execution. `FillMode`	`"auto"`
`iterations`	The number of iterations to run before the animation completes.	`Infinity`
`iterationStart` `iteration-start`	The offset at which to start the animation, usually between 0 (start) and 1 (end). `number`	`0`
`keyframes`	The keyframes to use for the animation. If this is set, the `name` attribute and property will be ignored. `Keyframe[] \| undefined`	-
`playbackRate` `playback-rate`	Sets the animation’s playback rate. The default is `1`, which plays the animation at a normal speed. Setting this to `2`, for example, will double the animation’s speed. A negative value can be used to reverse the animation. This value can be changed without causing the animation to restart. `number`	`1`
`currentTime`	Gets and sets the current animation time. `CSSNumberish`	-
`updateComplete`	A read‐only promise that resolves when the component has finished updating.	-

Learn more about attributes and properties.

Slots

Name	Description
(default)	The element to animate. Avoid slotting in more than one element, as subsequent ones will be ignored. To animate multiple elements, either wrap them in a single container or use multiple `<pc-animation>` elements.

Learn more about using slots.

Methods

Name	Description	Arguments
`cancel()`	Clears all keyframes caused by this animation and aborts its playback.	-
`finish()`	Sets the playback time to the end of the animation corresponding to the current playback direction.	-

Learn more about methods.

Events

Name	Description	Event detail
`pc-cancel`	Emitted when the animation is cancelled.	-
`pc-finish`	Emitted when the animation finishes.	-
`pc‐start`	Emitted when the animation starts or restarts.	-

Learn more about events.

Importing

If you’re using the autoloader or the standard loader, you can ignore this section. If you’re cherry picking, you can use any of the following snippets to import this component.

Script

Import

Bundler

To import this component from the CDN with a script tag, copy this snippet and paste it in your HTML.

<script type="module" src="https://cdn.jsdelivr.net/npm/placer-toolkit@0.5.1/dist/components/animation/animation.js"></script>

To import this component from the CDN using a JavaScript import, copy this snippet and paste it in your JavaScript:

import "https://cdn.jsdelivr.net/npm/placer-toolkit@0.5.1/dist/components/animation/animation.js";

To import this component with a bundler using a JavaScript import, copy this snippet and paste it in your JavaScript:

import "placer-toolkit/dist/components/animation/animation.js";