IOS status bar

- (BOOL)prefersStatusBarHidden; 

如果想利用UIApplication来管理状态栏，首先得修改Info.plist的设置

UIApplication *app = [UIApplication sharedApplication];
[app setStatusBarHidden:YES withAnimation:UIStatusBarAnimationFade];
[app setStatusBarStyle:UIStatusBarStyleLightContent animated:YES];
//    app.statusBarHidden = YES;
//    app.statusBarStyle = UIStatusBarStyleLightContent;

IOS status bar

原文：http://blog.csdn.net/zhangping871/article/details/40304043