我正在使用多个视图控制器和导航控制器开发应用程序。当应用程序运行并执行以下代码时,它会在尝试添加子视图时抛出异常。
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[self.window addSubview:[navigationController view]];
[self.window makeKeyAndVisible];
}
我声明导航控制器如下:
@interface SimpleContactsAppDelegate : NSObject <UIApplicationDelegate> {
NSManagedObjectModel *managedObjectModel;
NSManagedObjectContext *managedObjectContext;
NSPersistentStoreCoordinator *persistentStoreCoordinator;
UIWindow *window;
UINavigationController *navigationController;
// view for adding new contacts
UIViewController *newContactView;
UIButton *addButton;
// controls for the addContactView
UIButton *saveContactButton;
UITextField *nameField;
UITextField *emailField;
UITextField *phoneField;
UITableView *contactsTable;
}
@property (nonatomic, retain, readonly) NSManagedObjectModel *managedObjectModel;
@property (nonatomic, retain, readonly) NSManagedObjectContext *managedObjectContext;
@property (nonatomic, retain, readonly) NSPersistentStoreCoordinator *persistentStoreCoordinator;
@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) IBOutlet UINavigationController *navigationController;
@property (nonatomic, retain) IBOutlet UIButton *addButton;
@property (nonatomic, retain) IBOutlet UITableView *contactsTable;
// controller and fields for the form
@property (nonatomic, retain) IBOutlet UIViewController *newContactView;
@property (nonatomic, retain) IBOutlet UITextField *nameField;
@property (nonatomic, retain) IBOutlet UITextField *emailField;
@property (nonatomic, retain) IBOutlet UITextField *phoneField;
@property (nonatomic, retain) IBOutlet UIButton *saveContactButton;
我已将导航控制器连接到XIB中的Delegate对象。请随意查看我的完整资料来源:https://github.com/agmcleod/SimpleContacts/tree/parttwo
我尝试过使用带有NSZombie的乐器,但它似乎并没有停下来让我检查出现了什么特别错误。它也只是有时保持运行,并且不会终止。我最终不得不强制使用活动终端退出它。
答案 0 :(得分:3)
首先,您声明了一个属性,但是通过其实例变量而不是使用该属性来访问UINavigationController。
使用此:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[self.window addSubview:[self.navigationController view]];
[self.window makeKeyAndVisible];
return YES;
}
其次,您将主nib文件的名称更改为“Window.xib”。您必须将其更改回“MainWindow.xib”,否则您必须编辑SimpleContacts-Info.plist并将“主nib文件基本名称”的值更改为“Window”。