Progressive Share Button

The Progressive Share Button web component is a simple way to add a share button to your web page that will show the user the OS native share options using the Web Share API. The "progressive" part of the name comes from the fact that the component will only display the share button if the browser supports the Web Share API. If the browser does not support the Web Share API, the component will not display anything.

The web component is a wrapper around the Web Share API that attempts to display a share icon appropriate to the user's device with icons that will be recognizable to iOS/Mac, Android and Windows. If the device type can't be determined, the component will display a Windows share icon.

Basic Usage

The most basic usage of the component is to pass the URL to be shared. The component will render a share icon that will open the native share dialog when clicked.

Basic Example: <progressive-share-button url="https://example.com" />

This will render one of the following, depending on the device and browser. This example shows the Windows sharing icon, the Android sharing icon, and the iOS sharing icon.

Limitations

The Web Share API, while still in draft, has wide support on mobile. Desktop support is decent on Windows. Mac support works in Safari, but lags on third-party browsers. Check caniuse/web-share for the most up-to-date information on its progress.

The component will only display the share button if the browser supports the Web Share API. If the browser does not support the Web Share API, the component will not display anything.

Progressive Share Button does not support the sharing of files.

Installation as a module

The component is available as an npm module. Run the following command to install it.

npm install progressive-share-button

main.js, if installed with npm

// Import the component, which is the default export, so no curly braces are needed.
import ProgressiveShareButton from 'progressive-share-button';
// Initialie the component
ProgressiveShareButton();

Customizing the component name

If you want to customize the component name, you can import the element class directly and register it with a different name. Take note of the curly braces used in the import statement. This is a named import.

import { ProgressiveShareButtonElement } from 'progressive-share-button';
// Initialie the component
customElements.define('my-share-button', ProgressiveShareButtonElement);

CDN - not tested yet

Not Tested: You can also use the component directly from a CDN. The component is available on unpkg.

<!-- script src="https://unpkg.com/progressive-share-button"></script --!>

Typescript support

WIP: ~~~The component is written in Typescript and includes a type definition file. If you are using Typescript, you can import the component directly into your project.~~~

Customizing the Component

The component accepts the following attributes:

Styling

The component uses the Shadow DOM to encapsulate the styles. This means that the styles are not inherited by the parent page. To style the component, you must use the ::part() pseudo-element. There are two parts that can be styled: shareButton and shareIcon.

The basic Shadow DOM strutcture of the component is as follows:

<progressive-share-button>
  <button part="shareButton">
    <slot>
      <svg part="shareIcon">
        <!-- content of SVG here -->
      </svg>
    </slot>
  </button>
</progressive-share-button>

If you place style directly on the component, i.e., the progressive-share-button element, you may have unintended visual glitches on devices that would normally not display the share button. For example, if you place a background color and padding on the component, the background color will be displayed on devices that do not support the Web Share API.

The shareButton part

The shareButton part is the button that is displayed when the Web Share API is supported. The button is a button element. The button has the following default styles:

button {
  background: none;
  border: none;
  padding: 1px 2px 1px 2px;
  margin: 0;
  cursor: pointer;
}

The shareIcon part

The shareIcon part is the icon that is displayed when the Web Share API is supported. The icon is an svg element. The icon has the following default styles:

svg {
  width: 24px;
  height: 24px;
  fill: currentColor;
  vertical-align: bottom;
}

Usage examples

Basic usage

As shown earlier, the most basic usage of the component is to pass the URL to be shared. You may also pass the title and text to be shared.

<progressive-share-button url="https://example.com" />

<progressive-share-button title="Example.com" url="https://example.com" />

<progressive-share-button title="Example.com" text="The example.com URL is a useful placehold during web development." url="https://example.com" />

Replacing the share icon with text

You can replace the share icon with text by inserting text into the component's slot. The following example replaces the share icon with the text "Share this link". The text is styled using the ::part() pseudo-element named shareButton to apply the updated style to the button. This example also shows how you can target the component by assigning the text-share-example-1 class to the element.

<progressive-share-button url="https://example.com" class="text-share-example-1">Share this link</progressive-share-button>

<style>
progressive-share-button.text-share-example-1::part(shareButton) {
  font-size: 1rem;
  text-decoration: underline;
  color: blue;
}
</style>

Advanced usage with options

In the following example, the component is assigned the text-share-example-2 class. The component is styled using the ::part() pseudo-element named shareIcon to apply the updated style to the icon. The component is also assigned the smart-share attribute to pass the title, text, and url as a single string to the Web Share API. The icon will be displayed at 20 pixels wide and high.

<progressive-share-button
  title="Example.com"
  text="The example.com URL is a useful placehold during web development."
  url="https://example.com"
  smart-share=1
  icon-size=20
  class="text-share-example-2"
/>

<style>
progressive-share-button.text-share-example-2::part(shareIcon) {
  font-size: 1rem;
  text-decoration: underline;
  color: blue;
}

Why use the "smart-share" feature?

The smart-share feature is an attempt to address a situation that might be viewed as a bug in the implementation of the Web Share API on some platforms. The Web Share API requires that the data to be shared be passed as an object with the following optional properties:

• title
• text
• url

The Progressive Share Button web component by default simply passes your data to the Web Share API, like this:

{
  title: 'Example Page',
  text: 'This is an example page.',
  url: 'https://example.com'
}

The problem is that when multiple properties are passed as separate properties what actually gets shared doesn't always include all the pieces of data you pass into the API. Some devices and applications receiving the data object will only share a single property, most often the URL in my tests.

If smart-share attribute is true, the component will concatenate all of the data into a single string and pass it to the Web Share API as text. The title and text will have a period added at the end of the string if it is not present. This will allow the data to be shared on any device or application that supports sharing text. The data will be shared as a single string, like this:

{
  text: 'Example Page. This is an example page. https://example.com'
}

The following link lets you test the Web Share API on your devices to make a more informed decision as to what option works best for your use case.

https://w3c.github.io/web-share/demos/share-files.html

Custom events

There are two custom event emitted by the component: progressive-share-success and progressive-share-fail.

// example of listening for the custom events
document.addEventListener('progressive-share-success', (e) => {
  // e.detail contains the share data that was shared
  console.log('The progressive-share event was heard.', e.detail);
});
document.addEventListener('progressive-share-fail', (e) => {
  // e.detail contains the error message
  console.log('The progressive-share-fail event was heard.', e.detail);
});

Demo

https://johnfmorton.github.io/progressive-share-button/

License

MIT

Author

John F. Morton