Where put business logic and manage navigation from pages?

General
1

Hi all,
i’m a newer vaadin user.
it is a very usefull tool, but i have some doubt.
What i want to realize is to simple application that show a list of contents and then when i select one of them i can edit it or create a new one.
Here my questions:

  1. is not clear to me where to put my business logic.
  • In the Application.init() method? I think no, because it is called just one time and is not possibile to read http params.
  • in the “onRequestStart” method implementing the “HttpServletRequestListener”? It is called ad every browser refresh o and also befor init… so i can use it. My doubt is that i need to declare a global attribute containing my business data so that the init method can access to it.
    There is a best practice that someone can suggest to me?
  1. Generally speaking, how to handle the navigation from different pages? For example how to switch from a “listing page” to a “detail page” ? In a normal web application i can do this openening different page with the necessary http params. Witch is the best way with vaadin? for example the listing page and detail page must be created with different Application class? or is better to have only one application that manage all "pages

Thanks
Davide

2

Have you read the
Book of Vaadin
? If not, I would recommend starting there.

Otherwise, the
Vaadin Sampler
 has many useful examples of business logic and navigation. For each sample, you can click on View Source to see how it’s done.

3

Thanks Marlon!
I readed the vaading book and i found it very usefull.
Starting developing with vaadin is not “immediate”, but after a few days everything is very simple and intuitive.
It is a great tool!