Folks, I'm trying to make GWT 2.1 MVP work nicely with GIN. It looks like this use case was specifically considered when creating PlaceHistoryMapperWithFactory, but no such thing seems to exist for ActivityMapper. There is a passing reference to using Gin in DevGuideMvpActivitiesAndPlaces.html , where it says "... ClientFactory is used by HelloActivity to obtain a reference to the HelloView as well as the EventBus and PlaceController. Any of these could alternatively be injected via GIN." and also when it says "A better way to implement the chain of nested ifs would be with a GIN module", in reference to ActivityMapper.
The problem, however, is that we cannot both inject application-level objects (EventBus, PlaceController, etc) and also pass the Place as constructor arguments to the Activity. We could have all of the dependencies for every Activity (like all the views) injected into our ActivityMapper and pass them thru, but this leaks a lot of details into what should be a very simple mapper class. If done incorrectly, it would also cause code-splitting issues. One way around this is to inject a Provider<MyActivity> or AsyncProvider<MyActivity> in the ActivityMapper and then do something like myActivityProvider.get().initPlace(place) - which is like the assisted injection that's discussed in the Guice docs. I'm wondering if there's a more elegant way that was considered? Additionally, I'm not sure I understand how to "implement the chain of nested ifs" in a GIN module. This sounds like a great idea, but what did you have in mind to make GIN do this for us? We can have GIN differentiate on a bunch of things (annotations, generics, interfaces, etc), but I don't know how you could replace the if-block with GIN. Could someone point me in the right direction here? Thanks, Tolga -- http://groups.google.com/group/Google-Web-Toolkit-Contributors
