Я использовал файл .xib и соответствующие ему файлы .h и .m, чтобы показать простой сканер штрих-кода в моем приложении. Код Appdelegate имеет вид:
#import "AppDelegate.h"
#import "BarcodeScannerVC.h"
@interface AppDelegate ()
@end
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.
self.window = [[UIWindow alloc]initWithFrame:[[UIScreen mainScreen] bounds]];
BarcodeScannerVC *homeVc = [[BarcodeScannerVC alloc]initWithNibName:@"BarcodeScannerVC" bundle:nil];
UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:homeVc];
self.window.rootViewController = nav;
[self.window makeKeyAndVisible];
return YES;
}
#pragma mark - UISceneSession lifecycle
- (UISceneConfiguration *)application:(UIApplication *)application configurationForConnectingSceneSession:(UISceneSession *)connectingSceneSession options:(UISceneConnectionOptions *)options {
// Called when a new scene session is being created.
// Use this method to select a configuration to create the new scene with.
return [[UISceneConfiguration alloc] initWithName:@"Default Configuration" sessionRole:connectingSceneSession.role];
}
- (void)application:(UIApplication *)application didDiscardSceneSessions:(NSSet<UISceneSession *> *)sceneSessions {
// Called when the user discards a scene session.
// If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
// Use this method to release any resources that were specific to the discarded scenes, as they will not return.
}
@end
Но, по незнанию, происходит сбой приложения в строке «self.window», которую можно увидеть на изображении ниже:
![enter image description here](https://i.stack.imgur.com/RgiIM.png)
![enter image description here](https://i.stack.imgur.com/wmUvo.png)
Это структура файла:
![enter image description here](https://i.stack.imgur.com/7JLBd.png)
В чем проблема?