The file should be uploaded in the background via Ajax or Iframes. I should be able to detect via javascript when the upload has completed, so I can hide the loading graphic and redirect the user to a new URL. Using Jquery is fine.
Check out jQuery Uploadify
EDIT: There's also a similar question: how-to-upload-file-jquery - you could display the graphic after the upload button has been clicked and hide in the success/onerror function callback.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With