How to convert Android App to Samsung Galaxy S2

I have an apps built in Android 2.2. I need to port it for Samsung Galaxy S2. and its version is Android 2.3. Changing the version is done. But how can i fix up the screen resolution issues. Previously i developed for 240x320. Now it is 480 x 800. My question is from which folder the layout xml is readed. Samsung Galaxy S2 is small or normal or large or xlarge screen. Please answer me guys. Thanks in advance.

Thanks & Regards
Gokul.K

You shouldn't have to change the version. Later Android versions are supported automatically. If you set to manifest attributes to reflect Android 2.3, then the app will no longer run on 2.2 (which is still used by a large percentage of Android devices).

You should read http://developer.android.com/guide/practices/screens_support.html about how to develop for multiple screen sizes. http://developer.android.com/guide/practices/tablets-and-handsets.html (and all the other pages in the "Best Practices" section) should also be of interest.

For both older and newer version layout will be read from layout-normal folder. And to support 480 x 800 resolution which is high resolution, you need to put newly designed images in drawable-hdpi folder. Images should be in better resolution then previous images.