报错信息：failed with exit code 255

Command /Applications/Xcode.app/Contents/Developer/usr/bin/ibtool failed with exit code 255

• clean your project

• delete the cached data (Organizer->Projects->Derived Data tap 'Delete...'

• insure that for this XIB the proper

• versioning is set (select XIB, 3rd Xcode tab on right, File options:
  close the project

• quit Xcode

• reopen Xcode, then the product

• try again

Push 所要做的内容：

self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
self.window.backgroundColor = [UIColor whiteColor];
UINavigationController *nav= [[UINavigationController alloc]init];
self.window.rootViewController = nav;
    
ViewController  *rootView = [[ViewController  alloc] init];
[nav addChildViewController:rootView];
    
[self.window makeKeyAndVisible];

iOS 9 HTTP 请求报错：

App Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app's Info.plist file.

• 解决方案：

1.在 Info.plist 中添加 NSAppTransportSecurity 类型 Dictionary。
2.在 NSAppTransportSecurity 下添加 NSAllowsArbitraryLoads 类型 Boolean, 值设为 YES