<>ios14.3 Development using pure code creation UITabbarController

Here we are IOS edition 14.3.Xcode
Version selection is .12.3 edition ; come from apple abreast of the times xcode edition , This version supports the latest swift Grammar and minimal bug, Support for new api function .
Number of celebrities , Look at the present . Try to be as good as before apple ios The system is perfect , Apple is always bringing forth new things , We have to learn and use new technology ios system . Source code please in my home page Resource library search .

scene scene Two files to delete .m and .h Get rid of all the papers
main.stroyboard delete ,plist What should be deleted should be deleted ,
delegate.h Header file Add a code
@property(nonatomic,strong)UIWindow *windows; // use strong Make strong references
AppDelegate.m Write off useless and redundant code , Or delete it ; That's it
set up window The root controller of is created for pure code tabbarViewController
The core code is as follows ;
Don't worry about reporting mistakes , Search for documents , Be sure to learn .
// // AppDelegate.m // 23-tabbarController // // Created by Lu Jun on 2021/2/14. //
#import "AppDelegate.h" @interface AppDelegate () @end @implementation
AppDelegate- (BOOL)application:(UIApplication *)application
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { // Override point
for customization after application launch. self.window =[[UIWindow alloc]
initWithFrame:[UIScreen mainScreen].bounds]; UITabBarController *tab =[[
UITabBarController alloc] init]; UIViewController *v1 = [[UIViewController alloc
]init]; UIViewController *v2 = [[UIViewController alloc]init]; UIViewController
*v3 = [[UIViewController alloc]init]; v1.view.backgroundColor=[UIColor grayColor
]; v2.view.backgroundColor=[UIColor orangeColor]; v3.view.backgroundColor=[
UIColor blueColor]; v1.tabBarItem.title = @" news "; v2.tabBarItem.title = @" contacts ";
v3.tabBarItem.title = @" set up "; //tab_recent_nor tab_buddy_nor tab_me_nor v1.
tabBarItem.image=[UIImage imageNamed:@"tab_recent_nor"]; v2.tabBarItem.image=[
UIImage imageNamed:@"tab_buddy_nor"]; v3.tabBarItem.image=[UIImage imageNamed:
@"tab_me_nor"]; v1.tabBarItem.badgeValue = @"999"; [tab addChildViewController:
v1]; [tab addChildViewController:v2]; [tab addChildViewController:v3]; self.
window.backgroundColor = [UIColor greenColor]; self.window.rootViewController =
tab; [self.window makeKeyAndVisible]; // NSLog(@"%@",tab.tabBar); //<UITabBar:
0x7fa179c077f0; frame = (0 519; 320 49); autoresize = W+TM; gestureRecognizers
= <NSArray: 0x600003b526d0>; layer = <CALayer: 0x600003551e40>> return YES; }