ios 使用xcode11 新建项目工程的步骤详解

- (void)scene:(UIScene *)scene willConnectToSession:(UISceneSession *)session options:(UISceneConnectionOptions *)connectionOptions API_AVAILABLE(ios(13.0)){
 
 self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
 
 //1.创建Tab导航条控制器
 UITabBarController *tabControl = [[UITabBarController alloc] init];
 tabControl.tabBar.barStyle = UIBarStyleBlack;
 
 //2.创建相应的子控制器（viewcontroller）
 ViewController *control = [[ViewController alloc] init];
 control.tabBarItem = [[UITabBarItem alloc] initWithTitle:@"first" image:[UIImage imageNamed:@"icon_contact_normal"] selectedImage:[UIImage imageNamed:@"icon_contact_normal"]];
 UINavigationController * nav = [[UINavigationController alloc]initWithRootViewController: control];
 
 ViewController2 *control2 = [[ViewController2 alloc] init];
 control2.tabBarItem = [[UITabBarItem alloc] initWithTitle:@"first" image:[UIImage imageNamed:@"icon_contact_normal"] selectedImage:[UIImage imageNamed:@"icon_contact_normal"]];
 UINavigationController * nav2 = [[UINavigationController alloc]initWithRootViewController: control2];
 
 //将Tab导航条控制器设为window根控制器
 self.window.rootViewController = @[nav, nav2];
 
 //显示window
 [self.window makeKeyAndVisible];
 
}