How can I add UIView object to self.view.window in ios7? - ios

Question

I'd like to add a dark view layer that covers the whole screen.
In order to do that, I added UIView object to window property of UIViewController as shown below.I remember I was able to add a view to window like this in ios6. But, it doesn't work in ios7.
How am I able to make it work?
Thanks in advance!!
- (void)viewDidLoad
{
[super viewDidLoad];
UIView *overlayView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, [UIScreen mainScreen].bounds.size.height)];
overlayView.backgroundColor = [UIColor blackColor];
overlayView.alpha = 0.8;
[self.view.window addSubview:overlayView];
}

Answer 1

Here's one way of doing what you want:
[[UIApplication sharedApplication].keyWindow addSubview:overlayView];

Answer 2

According to the documentation of UIView, the window property is nil if the view has not yet been added to a window which is the case when viewDidLoad is called.
You can do the same thing in viewDidAppear:(BOOL)animated;
- (void)viewDidAppear:(BOOL)animated; {
UIView *overlayView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, [UIScreen mainScreen].bounds.size.height)];
overlayView.backgroundColor = [UIColor blackColor];
overlayView.alpha = 0.8;
[self.view.window addSubview:overlayView];
}

Answer 3

Swift 3
UIApplication.shared.keyWindow?.addSubview(overlayView);

Answer 4

you can try like this
- (void)viewDidLoad
{
[super viewDidLoad];
UIView *overlayView = [[UIView alloc] initWithFrame:self.view.frame];
overlayView.backgroundColor = [UIColor blackColor];
overlayView.alpha = 0.8;
overlayView.center = self.view.center
[self.view addSubview:overlayView];
}
i hope will helpful for you...