Upload progress indicator bar

Hello guys, first let me thank you for the great plugin you did.

I was experimenting with the progress bar indicator and it is working great, my only concern is that the progress bar shows before a file is attached for upload. I was wondering if you can consider hide the bar and show it once the “Upload” or “Submit” button is hit?

Thank you in advance.

http://ww.wp.xz.cn/plugins/simple-dropbox-upload-form/