Xcode and iOS apps tips & tricks for beginners continued (part 4)

How to reset the DNS cache
Okay, not really specific to development, but I’ve had issues with my WiFi (thank you Mac for not providing Ethernet…) which lead my DNS cache to mistakenly record DNS lookup failures.
The latest command (run it as su or with sudo) is killall -HUP mDNSResponder, on today’s Mac OS 10.11.2. For commands for other versions, see this help page from Apple.

How to create an unwind segue
Detailed guide there with picture. Short summary:

• In the view that will receive the segue, crate a function -(IBAction)unwindToSomePlace:(UIStoryboardSegue *)segue {...} (Objective-C) or @IBAction func unwindToSomePlace(segue: UIStoryboardSegue) {...} (Swift)
• In the view that will perform the segue, CTRL+click the view controller and drag it to the Exit (of the same view). Xcode will then show you a list of all unwind segues on the storyboard and you can pick unwindToSomePlace
• Give an identifier to the segue this added to your storyboard (the easiest place to find it is probably in document outline of the view that will perform the segue), for instance name it “unwindToSomePlaceSegue”
• To perform the segue: [self performSegueWithIdentifier:@"unwindToSomePlaceSegue" sender:self] (Objective-C) or self.performSegueWithIdentifier("unwindToSomePlaceSegue", sender:self) (Swift)