Rotating is always seen as a page refresh on Android. Normally this should go pretty fast if you cached your information correctly.
You should not use the onCreate method of your activity to load the information, the information should be loaded in a different place. But I suggest you have browse through some tutorials how you can do this. As this is not that easy to explain.
Or as Fraggle222 suggested, find your answer on site like StackOverflow. I even think there will probably already some (answered) questions concerning this problem.
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