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javagwtmvpfragment

Fragments, GWT.runAsync and AsyncProvider

My understanding is that GWT.runAsync is called any time you wish to implement "codesplitting" and trigger a new exclusive fragment to download.

My understanding is that it is recommended (by GWT) to design/develop functionality for a particular fragment in such a way that it can be downloaded once into a singleton instance of AsyncProvider and reused again and again.

My questions are:

  1. If I'm using an MVP pattern, does this "AsyncProvider" style apply to models, views and presenters? In other words, do I have to code in such a way that Model/View/Presenter "MVP-1" doesn't reference code inside of Models/Views/Presenters "MVP-2", so that when an AsyncProvider calls GWT.runAsync and pulls down the fragment for MVP-1, its a nice, clean, dependency-free download? Or am I fundamentally misunderstanding the AsyncProvider pattern altogether?
  2. What is an AsyncProxy and how does it fit in here?
  3. Why would a fragment need to be reused again and again? In other words, what's the benefit of the AsyncProvider pattern to begin with?!?

Thanks in advance!

Solution

  • Code Splitting and MVP are 2 differents things, it means that you don't need MVP for code splitting, but it's a very good thing to do with MVP.

    Broadly speaking, a UI with GWT, it's lot of components (View/Presenter) put together, each component can be code with MVP or not. And when a component call an other component, you must use GWT.runAsync, if you want to split your code. So for the first question: yes, AsyncProvider works with MVP.

    For the others questions, I invite you to watch the Google I/O 2011 at 32:55, it's explained well.

    Personaly I use and recommend Code Splitting with Places & Activities, see issue 5129