details-dialog-element/README.md

<details-dialog> element

A modal dialog opened with a <details> button.

DEPRECATION WARNING

This web component has been deprecated. There are a number of accessibility concerns with this approach and so we no longer recommend using this component.

Accessibility and Usability Concerns

• Semantically, using a details-summary pattern for a dialog solution can be confusing for screen reader users.
• If the user performs a "find in page" operation on a website using details-dialog elements, the content on those elements will appear when they shouldn't.
• Opening the dialog does not disable scrolling on the underlying page.

GitHub are moving towards using a dialog Primer View Component which enforces certain aspects of the design (such as always having a close button and a title).

Installation

Available on npm as @github/details-dialog-element.

$ npm install --save @github/details-dialog-element

Usage

Script

Import as ES modules:

import '@github/details-dialog-element'

Include with a script tag:

<script type="module" src="./node_modules/@github/details-dialog-element/dist/index.js">

Markup

<details>
  <summary>Open dialog</summary>
  <details-dialog>
    Modal content
    <button type="button" data-close-dialog>Close</button>
  </details-dialog>
</details>

Deferred loading

Dialog content can be loaded from a server by embedding an [<include-fragment>][fragment] element.

<details>
  <summary>Robots</summary>
  <details-dialog src="/robots" preload>
    <include-fragment>Loading…</include-fragment>
  </details-dialog>
</details>

The src attribute value is copied to the <include-fragment> the first time the <details> button is toggled open, which starts the server fetch.

If the preload attribute is present, hovering over the <details> element will trigger the server fetch.

Events

details-dialog-close

details-dialog-close event is fired from <details-dialog> when a request to close the dialog is made from

• pressing escape,
• submitting a form[method="dialog"]
• clicking on summary, form button[formmethod="dialog"], [data-close-dialog], or
• dialog.toggle(false)

This event bubbles, and can be canceled to keep the dialog open.

document.addEventListener('details-dialog-close', function(event) {
  if (!confirm('Are you sure?')) {
    event.preventDefault()
  }
})

Browser support

Browsers without native custom element support require a polyfill.

• Chrome
• Firefox
• Safari
• Microsoft Edge

License

Distributed under the MIT license. See LICENSE for details.