Resize Observer

The Resize Observer component offers a thin, declarative interface to the ResizeObserver API.

The resize observer will report changes to the dimensions of the elements it wraps through the pc-resize event. When emitted, a collection of ResizeObserverEntry objects will be attached to event.detail that contains the target element and information about its dimensions.

<div class="resize-observer-overview">
  <pc-resize-observer>
      <span>Resize this box and watch the console ↘️</span>
  </pc-resize-observer>
</div>

<script>
  const container = document.querySelector(
      ".resize-observer-overview",
  );
  const resizeObserver =
      container.querySelector("pc-resize-observer");

  resizeObserver.addEventListener("pc-resize", (event) => {
      console.log(event.detail);
  });
</script>

<style>
  .resize-observer-overview {
      display: flex;
      align-items: center;
      justify-content: center;
      padding: var(--pc-spacing-xxxl) var(--pc-spacing-xxl);
      border: 2px solid var(--pc-input-border-color);
      border-radius: var(--pc-border-radius-l);
      overflow: auto;
  }
</style>

Code

Properties

Name	Description	Reflects	Default
`disabled`	Disables the resize observer. `boolean`		`false`
`updateComplete`	A read‐only promise that resolves when the component has finished updating.		-

Learn more about attributes and properties.

Slots

Name	Description
(default)	One or more elements to watch for resizing.

Learn more about using slots.

Events

Name	Description	Event detail
`pc-resize`	Emitted when the element is resized.	`{ entries: ResizeObserverEntry[] }`

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/resize-observer/resize-observer.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/resize-observer/resize-observer.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/resize-observer/resize-observer.js";