(Objective-C) SceneDelegate使用及移除注意事项

一) 项目中使用SceneDelegate

1）使用Main.StoryBoard(Default)

无需特殊处理，Xcode 11及其以上版本，默认生成使用'Main.StoryBoard'模板

2）不使用Main.StoryBoard

2.1）在info.plist文件中找到Storyboard Name键值对，将其移除

Storyboard Name

2.2）在Base.lproj文件夹中找到Main.storyboard，将其移除

Main

2.3）在侧边栏TARGETS下，选中General选项卡，找到Deployment Info项，在Status Bar Style选项中,勾选Supports multiple windows选项

Status Bar Style

2.4）在AppDelegate.h文件中，新增window属性

@property (strong, nonatomic) UIWindow *window;

2.5）打开SceneDelegate.m文件，在willConnectToSession代理方法中，创建window窗口，初始化rootViewController

- (void)scene:(UIScene *)scene willConnectToSession:(UISceneSession *)session options:(UISceneConnectionOptions *)connectionOptions {
    UIWindowScene *windowScene = (UIWindowScene *)scene;
    self.window = [[UIWindow alloc] initWithWindowScene:windowScene];
    self.window.frame = windowScene.coordinateSpace.bounds;
    self.window.rootViewController = ViewController.new;
    [self.window makeKeyAndVisible];
}

二) 项目中不使用SceneDelegate

1）使用Main.StoryBoard

1.1）在info.plist文件中找到Application Scene Manifest键值对，将其移除

Application Scene Manifest

1.2）打开AppDelegate.m文件，找到UISceneSession lifecycle代理方法，将其全部移除，
即configurationForConnectingSceneSession 和didDiscardSceneSessions两个方法

#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.
}

2）不使用Main.StoryBoard

2.1）在 info.plist 文件中找到 Application Scene Manifest 键值对，将其移除

Application Scene Manifest

2.2）在 info.plist 文件中找到 Main storyboard file base name 键值对，将其移除

Main storyboard file base name

2.3）在Base.lproj文件夹中找到Main.storyboard，将其移除

Main

2.4）在AppDelegate.h文件中，新增window属性

@property (strong, nonatomic) UIWindow *window;

2.5）打开AppDelegate.m文件，在didFinishLaunchingWithOptions代理方法中，创建window窗口，初始化rootViewController

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
    self.window.backgroundColor = UIColor.whiteColor;
    self.window.rootViewController = UITabBarController.new;
    [self.window makeKeyAndVisible];
    return true;
}