UIAlertView 之上的 UIView

在我的应用程序中，使用了锁定屏幕。有时一个UIAlertView如图所示，现在当用户将应用程序发送到后台并再次将其置于前面时，UIAlertview会显示在锁定屏幕上方。是否有可能添加一个UIViewController的观点高于一切，即高于UIAlertView?

你应该有这样的

UIWindow *mySpecialWindowForLockScreen = [[UIWindow alloc]initWithFrame:[[UIScreen mainScreen] bounds]];

//"Hey iOS Please put this window above all alert view"
mySpecialWindowForLockScreen.windowLevel = UIWindowLevelAlert+100;

UIViewController *lockScreenViewController = [[UIViewController alloc]init];//Lock Screen

lockScreenViewController.view.frame = mySpecialWindowForLockScreen.bounds;

mySpecialWindowForLockScreen.rootViewController = lockScreenViewController;


// In lockScreenViewController view you can add lock screen images and other UI stuff
mySpecialWindowForLockScreen.rootViewController.view.backgroundColor = [UIColor greenColor];

[mySpecialWindowForLockScreen makeKeyAndVisible];

每当您想隐藏 LockScreen 窗口时，只需通过 setHidden:YES 隐藏它即可。