This is a bit more complex, and not necessary unless you have a good reason to instantiate Dropzones programmatically.
Dropzone itself relies heavily on events. Everything that’s visual is created by listening to them. Those event listeners are setup in the default configuration of every Dropzone and can be overwritten, thus replacing the default behavior with your own event callback.
You should only do this when you really know how Dropzone works, and when you want to completely theme your Dropzone