The android app I am working on overrides the Application class to store lightweight state (username, gps location, etc) in static vars. Most of this state is set in OnCreate of the launch activity (username retrieved from prefs, location listener runs). Is it safe to rely on the launch activity to initialize the Application class? Are there any cases where the Application class might be re-created without the Launch activity also being created?
The question comes up because I ran into a null pointer exception accessing a variable in the Application class on resuming the app after the phone was asleep for several hours (the app was left in the foreground before phone went to sleep). Is it possible that the process was killed while the phone was asleep and on waking the phone, the Application class was re-created, the top activity in the stack was resumed, but the launch activity.onCreate wasn't run thus the Application class wasn't initialized?
Note that I have tried to test these kinds of scenarios by Forcing the App to stop using Settings / Manage applications. However, I'm not able to recreate the problem. On the next run, the Application class is created, followed by the launch activity.onCreate.
Is it safe to assume that the Application class instance will exist as long as the process, and that when the Application class is created it is equivalent to "restarting" the application ie. start with a new activity stack (and first activity on stack is the launch activity)?
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