UISB UIWindow

Xode11

SceneDelegate.m

#import "SceneDelegate.h"
#import "ViewController.h"
@interface SceneDelegate ()

@end

@implementation SceneDelegate


- (void)scene:(UIScene *)scene willConnectToSession:(UISceneSession *)session options:(UISceneConnectionOptions *)connectionOptions {
   if (@available(ios 13, *)) {
       if (scene) {
           self.window = [[UIWindow alloc] initWithWindowScene:(UIWindowScene *)scene];
           self.window.frame = CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, [UIScreen mainScreen].bounds.size.height);
           self.window.backgroundColor=[UIColor redColor];
           
           UIView* view=[[UIView alloc] initWithFrame:CGRectMake(100, 100, 150, 150)];
           view.backgroundColor=[UIColor orangeColor];
           [self.window addSubview:view];
           
           
           UIView* backview =[[UIView alloc] initWithFrame:CGRectMake(0, 0, 240, 360)];
           backview.backgroundColor=[UIColor blueColor];
           [backview addSubview:view];
           
           [self.window addSubview:backview];
           

           
           [self.window makeKeyAndVisible];
       }
   }

}