用home键以外的其他方式退出应用程序真的不是ios风格的方法。

我做了这个助手，虽然，没有使用私人的东西:

void crash()
{ [[NSMutableArray new] addObject:NSStringFromClass(nil)]; }

但对我来说还是不适合生产。它用于测试崩溃报告，或在核心数据重置后快速重新启动。只是使它安全不被拒绝，如果功能留在生产代码。

用home键以外的其他方式退出应用程序真的不是ios风格的方法。

我做了这个助手，虽然，没有使用私人的东西:

void crash()
{ [[NSMutableArray new] addObject:NSStringFromClass(nil)]; }

但对我来说还是不适合生产。它用于测试崩溃报告，或在核心数据重置后快速重新启动。只是使它安全不被拒绝，如果功能留在生产代码。

- (IBAction)logOutButton:(id)sender
{
   //show confirmation message to user
   CustomAlert* alert = [[CustomAlert alloc] initWithTitle:@"Confirmation" message:@"Do you want  to exit?" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"OK", nil];
   alert.style = AlertStyleWhite;
   [alert setFontName:@"Helvetica" fontColor:[UIColor blackColor] fontShadowColor:[UIColor clearColor]];
   [alert show];
}
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{

   if (buttonIndex != 0)  // 0 == the cancel button
   {
      //home button press programmatically
      UIApplication *app = [UIApplication sharedApplication];
      [app performSelector:@selector(suspend)];
      //wait 2 seconds while app is going background
      [NSThread sleepForTimeInterval:2.0];
      //exit app when app is in background
      NSLog(@"exit(0)");
      exit(0);
  }
}

你不应该直接调用函数exit(0)，因为它会立即退出应用程序，看起来就像你的应用程序崩溃了。所以最好是给用户显示一个确认提醒，让他们自己去做。

斯威夫特4.2

func askForQuit(_ completion:@escaping (_ canQuit: Bool) -> Void) {
    let alert = UIAlertController(title: "Confirmation!", message: "Do you want to quit the application", preferredStyle: .alert)
    alert.addAction(UIAlertAction(title: "Yes", style: UIAlertAction.Style.default, handler: { (action) in
        alert.dismiss(animated: true, completion: nil)
        completion(true)
    }))
    alert.addAction(UIAlertAction(title: "No", style: UIAlertAction.Style.cancel, handler: { (action) in
        alert.dismiss(animated: true, completion: nil)
        completion(false)
    }))
    self.present(alert, animated: true, completion: nil)
}

/// Will quit the application with animation
func quit() {
    UIApplication.shared.perform(#selector(NSXPCConnection.suspend))
    /// Sleep for a while to let the app goes in background
    sleep(2)
    exit(0)
}

用法:

self.askForQuit { (canQuit) in
     if canQuit {
         self.quit()
     }
}

点击这里查看问答:https://developer.apple.com/library/content/qa/qa1561/_index.html

Q: How do I programmatically quit my iOS application? There is no API provided for gracefully terminating an iOS application. In iOS, the user presses the Home button to close applications. Should your application have conditions in which it cannot provide its intended function, the recommended approach is to display an alert for the user that indicates the nature of the problem and possible actions the user could take — turning on WiFi, enabling Location Services, etc. Allow the user to terminate the application at their own discretion. WARNING: Do not call the exit function. Applications calling exit will appear to the user to have crashed, rather than performing a graceful termination and animating back to the Home screen. Additionally, data may not be saved, because -applicationWillTerminate: and similar UIApplicationDelegate methods will not be invoked if you call exit. If during development or testing it is necessary to terminate your application, the abort function, or assert macro is recommended

在iPadOS 13中，你现在可以像这样关闭所有场景会话:

for session in UIApplication.shared.openSessions {
    UIApplication.shared.requestSceneSessionDestruction(session, options: nil, errorHandler: nil)
}

这将在你的应用委托上调用applicationWillTerminate(_ application: UIApplication)，并在最后终止应用。

但要注意两件事:

这当然不是用来关闭所有的场景。(参见https://developer.apple.com/design/human-interface-guidelines/ios/system-capabilities/multiple-windows/) 它在iPhone的iOS 13上编译和运行良好，但似乎什么都不做。

更多关于iOS/iPadOS 13场景的信息:https://developer.apple.com/documentation/uikit/app_and_environment/scenes