title: dropzone.js show progress bar using manual ajax call
body: <p>Try to integrate react with dropzone using this library <a href="https://github.com/felixrieseberg/React-Dropzone-Component" rel="nofollow noreferrer">https://github.com/felixrieseberg/React-Dropzone-Component</a> but no luck, stuck for hours. File is uploaded but couldn't see any progress bar.</p>
  
  <pre><code>export default class PhotoUpload extends Component {
      constructor(props) {
          super(props);
  
          this.dropzone = null;
  
          // For a full list of possible configurations,
          // please consult http://www.dropzonejs.com/#configuration
          this.djsConfig = {
              acceptedFiles: "image/jpeg,image/png,image/gif",
              addRemoveLinks: true,
              autoProcessQueue: false
          };
  
          this.componentConfig = {
              iconFiletypes: ['.jpg', '.png', '.gif'],
              showFiletypeIcon: true,
              postUrl: 'no-url'
          };
  
          this.callback = (file) =&gt; {
  
              this.dropzone.processQueue();
  
              myApi.upload(file).then((e) =&gt; {
                  console.log('done upload '+e.filename+' to server');
              })
          }
      }
  
      render() {
          const config = this.componentConfig;
          const djsConfig = this.djsConfig;
  
          // For a list of all possible events (there are many), see README.md!
          const eventHandlers = {
              init: dz =&gt; this.dropzone = dz,
              drop: this.callback,
              addedfile: this.callback,
          }
  
          return &lt;DropzoneComponent config={config} eventHandlers={eventHandlers} djsConfig={djsConfig} /&gt;
      }
  }
  </code></pre>
  
  <p>Apparently, this line of code doesn't work : <code>this.dropzone.processQueue();</code></p>