Xcode11 工程里多了两个delegate文件:SceneDelegate.h/SceneDelegate.m.对于已经习惯用纯代码的朋友,如果还用以往的方式,在AppDelegate.m里面设置window.rootViewController,就会发现程序会报错了.下面直接说两种解决方案:
方案1:
在项目的info.plist文件中,把图中箭头两行都删除,然后就可以在SceneDelegate.m里面通过代码来实现window.rootViewController的设置,这个地方代码也是有点变化的,代码如下:
- (void)scene:(UIScene *)scene willConnectToSession:(UISceneSession *)session options:(UISceneConnectionOptions *)connectionOptions {
if ([scene isKindOfClass:[UIWindowScene class]]) {
UIWindowScene *windowScene = (UIWindowScene *)scene;
UIWindow *window = [[UIWindow alloc] initWithWindowScene:windowScene];
UIViewController *vc = [[UIViewController alloc] init];
vc.view.backgroundColor = [UIColor redColor];
window.rootViewController = vc;
self.window = window;
window.backgroundColor = [UIColor whiteColor];
[window makeKeyAndVisible];
}
}
方案2:
把info.plist 文件中的 Application Scene Manifest 这一项直接删除,
然后在AppDelegate.h中添加一个属性:window,Xcode11把这个属性删除了需要我们手动添加回来;然后还要删除AppDelegate.m中的两个方法:
//- (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.
//}
做完上面这些动作,就可以按照XCode11以前的方式,在AppDelegate.h中设置window.rootviewcontroller了.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
UIViewController *v1 = [UIViewController new];
UINavigationController *nvc = [[UINavigationController alloc] initWithRootViewController:v1];
v1.view.backgroundColor = [UIColor redColor];
self.window.rootViewController = nvc;
[self.window makeKeyAndVisible];
return YES;
}