HTML/JavaScript UI widgets GUI builder [closed]
Ext has (now had) a couple of GUI builders.
GUI Builder by tof2k (he admitted he had no time to work on it anymore when he released it)
Most of these are being replaced/made redundant by Ext Designer.
You may try web based sigma builder. It has more than 30 GUI components supported. This builder is pure JavaScript stuff, the only thing which need PHP is to save the generated script in the server side.
By the way, this builder is free and open source under LGPL license.