title: Flutter error "Multiple widgets used the same GlobalKey" - using ScreenShot with SocialShare plugins
body: <p>I'm not sure where to find the extra widget sharing the same global key as another widget in my app. I'm using the Screenshot and Social Share plugins.</p>
  <p><a href="https://pub.dev/packages/screenshot" rel="nofollow noreferrer">https://pub.dev/packages/screenshot</a></p>
  <p><a href="https://pub.dev/packages/social_share" rel="nofollow noreferrer">https://pub.dev/packages/social_share</a></p>
  <p>I'd like to upload a screenshot when sharing to social media such as Facebook Messenger. But I'm getting the following error in my console which occurred only after I added the screenshot controller;</p>
  <pre><code>Flutter Multiple widgets used the same GlobalKey
  </code></pre>
  <p>Where am I getting this problem?  I created the screenshot instance within the state;</p>
  <pre><code>class _StageBuilderState extends State&lt;StageBuilder&gt; {
      ScreenshotController screenshotController = ScreenshotController();
  </code></pre>
  <p>Here's the build;</p>
  <pre><code>Widget createViewItem() {
      return Screenshot(
      controller: screenshotController,
            Column(
               children: &lt;Widget&gt;[
                child: Image.network( myavatar),
                child: IconButton(
                   icon: Icon(Icons.share),
                  onPressed: () async {
                     await screenshotController.capture().then((image) async {
                     SocialShare.shareOptions(&quot;http://myurl&quot;, imagePath: image.path);
                        }
                     );
                   },
                ),
            ],
         ),
      ),
  }
  </code></pre>
  <p>So where's this extra widget sharing the same global key as something else in my app?  Where should I start troubleshooting?</p>