I looked for it and couldn't find it on the forum, I think it's a simple thing.
based on this topic:
http://forums.unigui.com/index.php?/topic/24462-detect-cancel-opendialog-in-tunifileuploadbutton/
and I will use a "UniHTMLFrame" instead of "unifileuploadbutton"
How do I need to simulate Click?
UniHTMLFrame1.JSInterface.JSCall('fileInputEl.dom.click', []); // Error
UniHTMLFrame1.JSInterface.JSCall('dom.click', []); // Error
UniHTMLFrame1.JSInterface.JSCall('clic