Question

I am having trouble grasping the correct way to implement a centralized data access for different resources.

I want to have a single class, call it DataAccess.class that will call from both a SQLiteDatabaseHelper.class and a ServerAccess.class depending on what is appropriate when I call it’s methods.

I thought extending DataAccess.class from a Service was the best approach so I can use ASyncTask for the ServerAccess.class. Now I am having doubts. The DataAccess.class needs to be accessible by most of the Activities in my Application, and I want it to stop when the Application does.

According to the google developer resources it sounds like a Service is well used for ongoing operations in the background but I am unsure how to handle the life cycle given the scope that I am trying to incorporate. Can I make the Service call startService() and stopService() internally when I use the DataAccess.class methods? Does it make sense to call it every time I access the Service or should this only happen once at the start and stop of the Application?

Thanks for the help,

Answer 1

I would recommend

1) Use all AsyncTask based solution because Service – Activity Communication is limited. (Unless of course you need to run something in the background) BUT I would love to hear the counterargument to this, why use a service instead.

2) Don’t use just one Facade like DataAccess but make it specific to your app functions (ie sort of like System Services in Android).

3) You should use factories just like Android does to get the DataAcccess object you need. This addresses second part of where you get DataAccess object. Follow same model as getting and Android System service.

4) Use Content Providers where indicated and manage as indicated in Android docs.

Update: I think these are sort of the Axioms of a good solution. Not the whole thing. I will update as we consider this in depth.