Is there anyway for jQuery to detect an upload?

Is there anyway for jQuery to detect an upload?

For example...

Upon uploading a file, jQuery will display a div-overlay or something saying "Upload in progress", then when the upload is finished/form is done submitting, the div-overlay is removed...

It would follow the concept of:

{this is just mockup code}

onUpload (#uploadform) {

display(#divOverlay);

}

onComplete(#uploadform) {

remove(#divOverlay);

}

Sorry if this is a stupid question. I'm a bit new to jQuery.