How to add UIView on the top of all views?

The recommended solutions which handle device orientation properly are

• podAGWindowView It will automatically deal with any rotation and framechanges so you won't have to worry about that.
• read and follow the official post https://developer.apple.com/library/content/qa/qa1688/_index.html

• Add your view to the first subview, instead of adding it to the window
  

  UIWindow* window = [UIApplication sharedApplication].keyWindow;if (!window)     window = [[UIApplication sharedApplication].windows objectAtIndex:0];[[[window subviews] objectAtIndex:0] addSubview:myView];

You can also add it to the window. It will not handle device orientation, though.

let window = UIApplication.sharedApplication().keyWindow!let view = UIView(frame: CGRect(x: window.frame.origin.x, y: window.frame.origin.y, width: window.frame.width, height: window.frame.height))window.addSubview(v);view.backgroundColor = UIColor.blackColor()

There is also one other method

Add the following method in the view will appear to add every time push/pop view controller

-(void)viewWillAppear:(BOOL)animated{     [super viewWillAppear:animated];     [[[UIApplication sharedApplication] keyWindow] addSubview:<yourViewObject>];}

And for remove this view in next class add the following lines of code

-(void)viewWillDisappear:(BOOL)animated{    [super viewWillDisappear:animated];    [<yourViewObject> removeFromSuperview]; }

@MaciekWrocław answere swift version

Swift2

 var appDelegate = (UIApplication.sharedApplication().delegate! as! AppDelegate) var backgrView = UIView(frame: CGRectMake(0, 0, UIScreen.mainScreen().bounds.size.width, UIScreen.mainScreen().bounds.size.height)) backgrView.backgroundColor = UIColor.redColor() backgrView.alpha = 0.6 window?.addSubview(backgrView)

swift3

     var appDelegate: AppDelegate? = (UIApplication.shared.delegate as? AppDelegate)     var backgrView = UIView(frame: CGRect(x: CGFloat(0), y: CGFloat(0), width: CGFloat(UIScreen.main.bounds.size.width), height: CGFloat(UIScreen.main.bounds.size.height)))     backgrView.backgroundColor = UIColor.red     backgrView.alpha = 0.6     window?.addSubview(backgrView)

and i am doing for my application about net connection in the AppDelegate:

func checkReachabilityUpdateUI() -> Int {    let remoteHostStatus = self.reachability?.currentReachabilityStatus()    if remoteHostStatus?.rawValue == 0 {        let backgrView = UIView(frame: CGRectMake(0, 60, UIScreen.mainScreen().bounds.size.width, 44))        let statusMessage = UILabel(frame: CGRect(x: 0, y: 0, width: UIScreen.mainScreen().bounds.size.width, height: 44))        statusMessage.text = "No internet Connection"        statusMessage.textAlignment = .Center        statusMessage.textColor =  UIColor.whiteColor()        backgrView.backgroundColor = UIColor.redColor()        backgrView.addSubview(statusMessage)        backgrView.tag = 100        window?.addSubview(backgrView)        return (remoteHostStatus?.rawValue)!    }    else {        if let viewWithTag = self.window!.viewWithTag(100) {            print("Tag 100")            viewWithTag.removeFromSuperview()        }        else {            print("tag not found")        }       return (remoteHostStatus?.rawValue)!    }}