iOS code to dismiss a View with countdown - ios

Question

Im experimenting with iOS 8 Objective-c project to perform a segue to a view controller right when viewDidLoad is presented.
Then this recent new presented view should be dismissed by a 30 seconds countdown to return to the initial view controller.
What would be like the code to dismiss the view with a countdown ? A countdown interface would not be necessary, just the background code.
My initial view controller is called ConfViewController and will perform a segue right on viewDidLoad to BubbleViewController, this should be displayed for 30s then be dismissed to the first one again ConfViewController.
#implementation ConfViewController
- (void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
- (void)viewDidLoad
{
[super viewDidLoad];
The BubbleViewController
#interface BubbleViewController ()
#end
#implementation MessagesViewController {
UIVisualEffectView *blurEffectView;
}
- (void)viewDidLoad
{
self.dataSource = self;
self.delegate = self;
[super viewDidLoad];
Thnx and cheers!

Answer 1

Putting this Code into your bubble view Controllers viewDidLoad or similar and it will dismiss itself after 30 seconds:
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(30 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[self dismissViewControllerAnimated:YES completion:nil];
});

Answer 2

A quick way to execute any code after some time is to use this snippet:
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
//code to be executed after a specified delay
});
Where you should place this code is up to you either in the presenters or in the presented controllers viewDidLoad.
How you should dismiss it depends on the way that you presented it.

Answer 3

Add below line of code in BubbleViewController's viewDidLoad method
//countdown can be according to requirement
[self performSelector:#selector(dissmissView) withObject:nil afterDelay:30];
Now description of dissmissView method and add these method also.
-(void)dissmissView
{
if (self.navigationController.presentingViewController)
{
//presented As ModaL
[self dismissViewControllerAnimated:YES completion:nil];
}
else if(self.navigationController)
{
//Pushed in navigation controller stack
[self.navigationController popViewControllerAnimated:YES];
}
else //added as subView
{
[self.view removeFromSuperview];
}
}