I'm working on pretty simple web side that cointains login screen (almost same as in demo presentation, white page with login and password) and main screen with sidebar and navigation bar. How should it be done? My plan is to build main screen using navigation bar, sidebar (just few buttons in layout basicly) and few layouts with content of the webside. On each button click change layout used to create content to another one, for example for Schudele button I'm gonna load layout that contains some tables, for About button plain text. Is it good idea?
So finnaly is should look like this: init() function decides if user is logged or not and display Login page or Main page, Main Page is builded from modules like navbar, sidebar and content, content depends on sidebar buttons click. I'm right?
Handling it on your own is legit way to start or learn Vaadin. If you have a first grasp of this works out, the most common way to handle such a scenario is the use of the Navigator See the book of Vaadin.
With the Navigator you define Views and give them a name, register them with the Navigator. Then you can navigate your application with the Navigator, it takes care to give you nice ...#!view... URLs so the Users can have bookmarks and navigate your app also e.g. with the back button in the browser.
The Navigator hooks into an event system, where listeners (ViewChangeListener) can react to "before enter" and "leave". The "before enter" can be used to realize auth needs, since they are allowed to object entering a view.