You should be able to log off using Settings, just like on a device.

You could have each real player device calculate the following AI move(s), and pass multiple moves to the next real player. Or, if you have a single “server” device, the turn can bounce back to

Hi, Game Centre doesn’t show up in the Simulator Settings….. In fact, when I open the settings App on the Simulator (iPhone 5s - iOS 10.3 (14E8301)), I can’t fully see the bottom item in the

Hi All, In the following code, does it *need* to use the dispatch_async function? dispatch_async(dispatch_get_main_queue(), ^{ if ([[self delegate]

It sounds like you’ve got an issue with Xcode and the Simulators. If you’ve been playing with beta Xcode and released Xcode at the same time, all sorts of weirdness can happen. Try quitting

Hi, I’m using XCode 8.3.3 is there a better/newer version available? I’m having all kind of issues with this version and wondered if worth updating? All the Best Dave

If you’re only using one Xcode, then you probably should do the regular things: quit Xcode, reboot, etc. I just tried that version and could scroll to the Game Center item in Settings. Also,

It's hard to understand because concurrency is the most difficult task in software engineering. (A debate on "hardest task" might be fun. Please let's not.) If the code you're looking at was

I’m glad that Fritz chimed in here before I risked an answer. My gut feeling was that, “well, even if it isn’t required, seeing the word ‘_async’ in the function clearly states to you that

Hi all, I have a property "velocity" that returns a custom object representing a 2D vector. That vector object has properties "x" and "y". From time to time, the value of velocity to be displayed

The call you showed runs the block on the main thread. That aspect may be crucial. Does the code this is part of run on a different thread/queue? Also, it can often be very useful to defer some code

Yes, that’s exactly the reason. By returning a new object from the getter, you are making the property non-KVO-compliant. KVO is reference-based, not value-based. When you observe the key-path

I think I would have a property that holds the velocity that is calculated in response to the keyPathsForValues… method being fired. Then just bind to that property. Make sure that everything that

KVO observes a known object. If you return another one, then you need to remove the observer from your old object and add it to your new one. KVO is going, “I’m looking at this thing.” If the

This represents a truth about KVO compliance for some scenarios, but the problem in this case is one level more subtle. The binding is observing the *wrong* instance of the velocity object. The only

The "Main thread checker" in XC 9 beta will tell you if you're doing something off the main thread that you shouldn't. It's really useful.

I have an application that presents a window to the user which floats above all other windows. It must be running at all times when any user is logged in. I achieve this with a launchd.plist

LaunchDaemons is the wrong directory; that’s for system daemons that run outside of any user context. (I’m surprised you actually got this to work, because it’s difficult to present any UI from

SMJobBless is a royal pain to get going. By far the easiest (and perhaps coolest) way of running a privileged app (usually for an installer) is to do it through AppleScript. Something like: “do

Jens, Thanks for your thoughts... It's not really a Daemon, it's an application that is persisted by Launchd.Yea my instinct said this wasn't right, but it just worked better in LaunchDaemons. Should