Share image via social media from PWA

In my Nuxt PWA I have a function that converts my HTML to Canvas using this package. The generated image is in base 64. Now I want to be able to share that image via: Whatsapp, Facebook, email, Instagram etc. I have found several packages but they all don't seem to support sharing files only URLs and Text.

This is my share function:

shareTicket(index) {
  html2canvas(this.$refs['ticket-' + index][0], {
    backgroundColor: '#efefef',
    useCORS: true, // if the contents of screenshots, there are images, there may be a case of cross-domain, add this parameter, the cross-domain file to solve the problem
  }).then((canvas) => {
    let url = canvas.toDataURL('image/png') // finally produced image url

    if (navigator.share) {
      navigator.share({
        title: 'Title to be shared',
        text: 'Text to be shared',
        url: this.url,
      })
    }
  })

When I take out the if (navigator.share) condition I get an error in my console that navigator.share is not a function. I read somewhere that it only works on HTTPS so I uploaded to my staging server and tried but still got the same error.

Just to be clear I want to be able to share the generated image itself and not a URL.

Tell me if this URL works for you: https://nuxt-share-social-media.netlify.app
If it does, you can find the Github repo here: https://github.com/kissu/so-share-image-bounty

The code is

<template>
  <div>
    <div id="capture" ref="element" style="padding: 10px; background: #f5da55">
      <h4 style="color: #000">Hello world!</h4>
    </div>

    <br />
    <br />
    <button @click="share">share please</button>
  </div>
</template>

<script>
import html2canvas from 'html2canvas'

export default {
  methods: {
    share() {
      // iife here
      ;(async () => {
        if (!('share' in navigator)) {
          return
        }
        // `element` is the HTML element you want to share.
        // `backgroundColor` is the desired background color.
        const canvas = await html2canvas(this.$refs.element)
        canvas.toBlob(async (blob) => {
          // Even if you want to share just one file you need to
          // send them as an array of files.
          const files = [new File([blob], 'image.png', { type: blob.type })]
          const shareData = {
            text: 'Some text',
            title: 'Some title',
            files,
          }
          if (navigator.canShare(shareData)) {
            try {
              await navigator.share(shareData)
            } catch (err) {
              if (err.name !== 'AbortError') {
                console.error(err.name, err.message)
              }
            }
          } else {
            console.warn('Sharing not supported', shareData)
          }
        })
      })()
    },
  },
}
</script>

Inspired from @denvercoder9!

---

More info about the answer

• I've used an IIFE because I was not sure how the whole thing works, but it's works great in a method context!
• I've added a missing async because ESlint and in case you wanted to make something after
• I've used $refs because this is how you should select specific parts of the DOM in the Vue ecosystem
• I've striped some things to keep it simple, hosted on Netlify to have some simple HTTPS and tested it on Chrome (v91), working perfectly fine!
• Here is the link again to the MDN documentation of the Web Share API.

---

Compatibility

This is my experience for the browsers (tested on the MDN example and on my app, exact same results)

For me, this was a mobile only feature (like for Android). But it looks like even some desktop browsers are handling this too. I have to admit that I was really surprised to even see this one work on Windows.
Here is an interesting post from Google that correlates this compatibility: https://web.dev/web-share/#browser-support

Reading MDN again, it says

The navigator.share() method of the Web Share API invokes the native sharing mechanism of the device.

So, I guess that the "(desktop) device" mostly do not support the Share API.

TLDR: this is working totally as intended but the compatibility is really subpar so far.