UIView frame size doesn't set properly in Portrait mode in iPad?

Question

Hi Friends,

Now i am working an iPad application.When i runs the application in portrait and Face up mode the view doesn't set the frame properly. After that rotating the view, the frame size is to be sets properly in the portrait and Face up mode. I don't know why its happened?. Please give me some idea for that?

In portrait and FaceUp -- (Initially loaded the frame size is (0,-20,768,1024) automatically set which means frame is -20y moves to Up). After rotating the view, the frames are set to be properly.

Please Help me out.