Poor performance until orientation change

Question

I have a MainActivity that extends SherlockActivityFragment. This activity holds some fragments and a menu. Each menu item leads to new SherlockActivities. One particular SherlockActivity when it is loaded contains a carousel, that moves extremely slow.

However, once the orientation changes this carousel performs perfectly. I know that the Activity is reloaded on orientation change. But I have no idea what could start this to begin with, or even where to start looking.

Has anyone come across any similar issues? What did you do to profile the issue and what was your fix?

If you can think of relevant parts of the code (eg onCreate etc) please ask and I'll post it. Each activity has about 150 - 200 LoC)

Edit:

Here is the intent that I am using to start the SherlockActivity in question:

Intent rankIntent = new Intent(context, RankActivity.class);
            rankIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            context.startActivity(rankIntent);
            break;

I've read that on orientation change onDestory() is called followed by onCreate. This makes me think that maybe some resource is freed that wasn't initially available. But the flag in the intent is intended to clear the backstack and any resources with it.

I've also tested with using the finish() method just before loading the new activity with no improvements.

Answer 1

This seems like a far reach but I recently had a problem I'd say could be similar. I learnt that Android doesn't handle scaling images particularly well - could it be that the images are scaled before you change the orientation and not scaled once you do?

Answering the 2nd part of your question: since my app doesn't perform any resource-needy logic operations and is based on its UI, what I did was comment out some of its elements one at a time to see if it helps; that's how I found out an ImageView that was scaled up in my case.