Our product, Elevate Web Builder, provides this type of functionality:

http://www.elevatesoft.com/products?category=ewb&type=web

For example, coding a button event handler is just like it is in Visual Studio/Delphi - just double-click on the button in the form designer and you're in the code editor positioned inside of an empty event handler code block.

Very cool.

There have been a few attempts. The autogenerated code isn't/wasn't all that great. I periodically use something like Quickbase, which lets you focused on the data collection and processing aspect, rather than where widgets go on the screen (VB3's UI being the first thing you interact with and what everything is tied to leads to some less than ideal maintenance nightmares).