title: Generating QR Code for vEvent gives error "No usable data found"
body: <p>I am trying to generate a QR code, that when scanned, will prompt the user to add an event to their calendar. I know that this is possible as I've used services like qrmonkey to generate codes that my iOS device will prompt me to do this.</p>
  <p>I've created a function that successfully generates a QR code and is scannable. The function is below.</p>
  <pre><code>func generateCalendarEvent(summary: String, location: String?, url: String?, description: String?, startDate: Date, endDate: Date) -&gt; UIImage? {
          //Generate Event String
          var eventString: String = &quot;BEGIN:VEVENT&quot;
          eventString.append(&quot;\nSUMMARY:\(summary)&quot;)
          if let locationString: String = location {
              eventString.append(&quot;\nLOCATION:\(locationString)&quot;)
          }
          if let urlString: String = url {
              eventString.append(&quot;\nURL:\(urlString)&quot;)
          }
          if let descriptionString: String = description {
              eventString.append(&quot;\nDESCRIPTION:\(descriptionString)&quot;)
          }
          eventString.append(&quot;\nDTSTART:\(startDate.formatted(format: &quot;yyyymmdd'T'hhmmss&quot;))&quot;)
          eventString.append(&quot;\nDTEND:\(endDate.formatted(format: &quot;yyyymmdd'T'hhmmss&quot;))&quot;)
          eventString.append(&quot;\nEND:VEVENT&quot;)
  
          //Setup Filter
          guard let filter = CIFilter(name: &quot;CIQRCodeGenerator&quot;) else {
              return nil
          }
          filter.setValue(eventString.data(using: .utf8), forKey: &quot;inputMessage&quot;)
          
          //Setup Transform
          let transform = CGAffineTransform(scaleX: 3, y: 3)
          
          guard let output = filter.outputImage?.transformed(by: transform) else {
              return nil
          }
          return UIImage(ciImage: output)
      }
  </code></pre>
  <p>When I scan the generated QR code though, it gives me an error on the iOS device saying &quot;No usable data found&quot;.</p>