android - Saving state of ArrayList of custom objects

Question

I have a member variable in my Activity which is an ArrayList. The objects populating this ArrayList are objects I have defined called RatingItem. RatingItem has several member vars like rating, comment, id, etc.

I would like to save this ArrayList in onSaveInstanceState so it can be repopulated from onRestoreInstanceState. What is the best way to do this? I've never saved the state of an object of this complexity.

Thank you for your help

Answer 1

You should probably have your object implement Parcelable. Basically, you have to add methods to write and read the members of your object from a Parcel, and then add custom CREATOR inner class that has a couple of static factory methods. There's a demo of it on the first linked page, but it's not too hard.

Then you can just save the whole list in one go with Bundle.putParcelableArrayList(). (You'll have to cast the list when you get it back out with Bundle.getParcelableArrayList() but it will work fine.)