UIView doesn't respond to touches - ios

Question

I have simple view controller and I add this controller like subview for window using this code:
UIWindow *window = [UIApplication sharedApplication].keyWindow;
if (!window)
window = [[UIApplication sharedApplication].windows objectAtIndex:0];
self.view.alpha = 0.0;
self.view.userInteractionEnabled = YES;
[window addSubview:self.view];
[self.view addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(closeTriggered:)]];
[UIView animateWithDuration:0.5 delay:0 options:UIViewAnimationOptionAllowUserInteraction animations:^{
self.view.alpha = 1.0;
}completion:nil];
But when I click at this view - nothing happens. Even event touchesBegan: are not called.
UPD:
Code above is in -(void)show method. I want to show one controller above all controllers.
In FirstViewController I create instance of CustonAlertViewController like that:
CustomAlertViewController *alertVC = [[CustomAlertViewController alloc]init];
[alertVC show];
In CustomAlertViewController I have show method presented at the top and viewDidLoad method with:
self.view.backgrondColor = [UIColor greenColor];

Answer 1

Hidden views (and equivalently, those with alpha == 0.0) do not respond to touches. If you require a fully transparent view, leave alpha as > 0.0, and say...
self.view.backgroundColor = [UIColor clearColor];
Alternatively, assign a nonzero alpha.
EDIT yes, the CustomAlertViewController instance is being deallocated immediately after show is invoked. The view controller that does the allocating needs to have a strong property to keep the alert around,
#property(nonatomic,strong) CustomAlertViewController *alertVC;
and adding...
CustomAlertViewController *alertVC = [[CustomAlertViewController alloc]init];
self.alertVC = alertVC;
[alertVC show];
This doesn't try to address some potential problems beyond the scope of this question (like rotation, or cleanly restoring when the alert is done).

Answer 2

// try like this , u need to give number of touches
UITapGestureRecognizer *gesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(closeTriggered:)];
gesture.numberOfTapsRequired = 1;
gesture.numberOfTouchesRequired = 1;
[self.view addGestureRecognizer:gesture];

Answer 3

You have been setting your UITapGestureRecognizer after you addSubview to your window. like:
You have been doing this
//...
[window addSubview:self.view];
[self.view addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(closeTriggered:)]];
//...
Try this
Set UITapGestureRecognizer before you addSubview. And remember to add the UIGestureRecognizerDelegate to your ViewController
self.view.alpha = 0.2;
self.view.userInteractionEnabled = YES;
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(closeTriggered:)];
tapGesture.numberOfTapsRequired = 1;
[tapGesture setDelegate:self];
[self.view addGestureRecognizer:tapGesture];
// After you add your self.view to window
[window addSubview:self.view];
I hope this can help you.