Dynamic Form Control

I want to create a web part with can be controlled by form control like that one used to add a proerties (image)

This control should behave lik that: 1.You can add a new item. When you do this you can change it's properties (another form control). 2.After save it should save evrything to collection 3.Control on page should be display by reading information from collection and generate text, divs, etc.

Any Ideas.