Search code examples
androidandroid-asynctaskandroid-sqlite

How to ensure that data will be saved before android kills a process


In Android it is generally a good practice to perform no database operation (or at least complex ones) in UI-Thread. I have an activity with a complex form and I want to ensure that all data is saved when the activity goes in the background (e.g. the user presses the home button or a phone call comes in). In the activity’s onPause()-method I can start an AsyncTask which stores the data in database but I can never be sure that the task finishes successfully because android can kill the process before the task finished because the activity and the whole app is in background.

I can save data synchron in the onPause-method but then it’s possible to run in to an ANR.
I know that Android restores the views after the activity was killed but this works only correct when View Ids are unique. I have a lot of programmatically added Views where I cannot ensure the Id’s uniqueness and to use the saveInstanceState-functionality is nearly impossible because I have to save very complex models.

Is there any possibility to ensure that data will be saved before android kills a process without doing it in the UI-Thread?


Solution

  • I created an application once where I had similar data consistency concerns. What I did there is delegate the storing of the data objects to a Service I created just for that purpose. Although this makes the starting/stopping/initialization of your Activity a lot harder (once the activity is started again, you will have to wait for the service to complete its previously started save action), this was the only "Android" way I could think of to deal with this problem.