Android - Storing Game State Information That Is Retained And Used Upon Next Start-Up

Question

I have an unlockable mode in my game that is only available once the story mode has been completed. This works perfectly if the story mode is completed during a test play through, because upon returning to the main menu the bonus mode is unlocked and selectable. However when I shut down the app and relaunch it, none of the previous state information is retained and it requires you to beat the story mode again to access the bonus mode.

I use the onSaveInstanceState method to create a bundle that stores this information (ie. a boolean whether the mode is unlocked or not), but this information seems to be lost between ending the app, and relaunching it. The onCreate method takes the parameter of a savedInstanceState but yet this seems to be null.

Is there a step that I'm missing out, or doing incorrectly somewhere along the line? On a PC game I would just serialize the state into a text file and look for a special string/symbol upon initialization but I cant do that here so i thought the outState bundle you create in SIS was how you retained information for use upon next launching the app again?

Answer 1

Look up SharedPreferences. It's very easy to use, and will last you until the app is uninstalled. http://developer.android.com/reference/android/content/SharedPreferences.html

onSaveInstanceState is really just to retain the state while the app is recreated because of an orientation change or something similar.

Answer 2

Check out the following webpage it tells you the various way you can store data. Shared preference is what I would suggest in your case

http://developer.android.com/guide/topics/data/data-storage.html#preferences