屏幕是横屏时，让页面也随着屏幕以横屏形式显示

用通知观察屏幕的情况

[[NSNotificationCenter
defaultCenter] addObserver:self

selector:@selector(rotate)

name:UIDeviceOrientationDidChangeNotification

object:nil

];
-(void)rotate
{

UIDeviceOrientation orientation = [UIDevice
currentDevice].orientation;

UIInterfaceOrientation interfaceOrientation = (UIInterfaceOrientation)orientation;

if (interfaceOrientation ==
UIInterfaceOrientationPortrait ) {

//竖屏操作

}else
if(direction ==
UIInterfaceOrientationLandscapeRight)

{

//横屏操作

}

}