问题描述
这是一个会影响许多应用程序的问题，可以在Xcode 8 beta(8S128d)中找到.这是第一个Beta，尽管它没有标记为beta 1.
This is an issue that will affect many apps, and can be found in Xcode 8 beta (8S128d). This is the first beta, although it is not labelled beta 1.
问题出在NSUserDefaults上；它不起作用.这是代码，也许将其放在 application:didFinishLaunchingWithOptions:中.
The issue is with NSUserDefaults; it doesn't work. Here's the code, maybe put it in application:didFinishLaunchingWithOptions:.
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setValue:@"hello world" forKey:@"TEST"];
[defaults synchronize];
NSString * oops = [[NSUserDefaults standardUserDefaults] valueForKey:@"TEST"];
NSLog(@"default = %@", oops);
在XCode 7和更早的版本中，此代码按预期工作: 的值为"hello world".
In XCode 7 and earlier, this code works as expected: the value of oops is "hello world".
在XCode 8中， oops 的值为 nil .
In XCode 8, the value of oops is nil.
这很重要！
推荐答案
找到了答案:https://forums.developer.apple.com/message/143155#143155
如果您使用过XCode 7或更早版本，则需要在运行iOS 10模拟器之前重新引导Mac.
If you've used XCode 7 or earlier, you need to reboot the Mac before running the iOS 10 simulator.
WWDC种子:运行多个iOS模拟器可能导致NSUserDefaults无法正常工作
WWDC Seed: Running multiple iOS simulatorscan cause NSUserDefaults to not work
运行iOS 8或9模拟器其次是iOS 10模拟器将导致NSUserDefaults停止在模拟器中工作.可以通过重新启动托管Mac.
Running an iOS 8 or 9 simulatorfollowed by an iOS 10 simulator will cause NSUserDefaults to stopworking in the simulator. This can be worked around by rebooting thehost Mac.
这篇关于为什么我的应用程序不能在XCode 8 beta(8S128d)中运行的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！