I'd like to know it if there is GXT tool to help me out.
What I have in mind is Client side code(Javascript) generating ui widgets/elements based on the data provided by server.
In other words, I want client side code to be nothing more than data loader. I want server to send responses that contains, view port settings, settings for individual views, panels, layouts, and tool bars, buttons, labels, form fields, etc.

For instance, take a look at the portal example. sample code is static.
I want GXT code to make a query what should be displayed to the server .
and the server responses, root panel is split into 3 regions. north, west and center
north is an empty layout container with 30px height
west is a content panel with accordion layout. its title is west.
it nests 2 content panels; navigation and settings
navigation content panel has a label.
label is "Lorem Ipsum is ...."
Center region is a content panel with portal layout.
it has 5 portlets : Grid in a portlet. ...
so on.

Is there GXT tool for this sort of code?