how to show the views added in view controller - ios

Question

I had created the the view programatically but it does not display on the screen
and gives a message in the console that
Failed to instantiate the default view controller for UIMainStoryboardFile 'Main' - perhaps
the designated entry point is not set?
Here is my code
-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary
*)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] ;
exmTableViewController *vc =[[exmTableViewController alloc] init];
self.window.rootViewController=vc;
self.window.backgroundColor =[UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
}
*Code In Viewdidload *
- (void)viewDidLoad
{
[super viewDidLoad];
UIImageView *img =[[UIImageView alloc] initWithFrame:CGRectMake(10, 10, 100, 20)];
self.imageView=img;
[self.view addSubview:self.imageView];
UILabel *lbl =[[UILabel alloc] initWithFrame:CGRectMake(10, 10, 100, 20)];
lbl.text =#"Hello";
self.view =lbl;
}

Answer 1

Instead this line self.view =lbl;, use [self.view addSubview:lbl]; to add subview to your view.

Answer 2

try this
- (void)viewDidLoad
{
[super viewDidLoad];
UIImageView *img =[[UIImageView alloc] initWithFrame:CGRectMake(10, 10, 100, 20)];
self.imageView=img;
[self.view addSubview:self.imageView];
UILabel *lbl =[[UILabel alloc] initWithFrame:CGRectMake(10, 10, 100, 20)];
lbl.text =#"Hello";
[self.view addSubview:lbl];
}

Answer 3

-(void)viewDidLoad
{
[super viewDidLoad];
UIImageView *img =[[UIImageView alloc] initWithFrame:CGRectMake(10, 10, 100, 20)]; [self.view addSubview:img];
UILabel *lbl =[[UILabel alloc] initWithFrame:CGRectMake(10, 200, 100, 20)];
lbl.text =#"Hello";
[self.view addSubview:lbl];
}
Try like this. self.view = lbl; in this line you assign self.view is as label you want to add subview [self.view addSubview:yourSubView]; do like this.

Answer 4

When you are creating View controller from storyboard, view controller is initiated by storyboard. You should not create windows root controller by yourself. You need to provide story board name in Plist.
After loading view viewDidLoad method will be called. Here you need to set up view(Adding and configuring subviews). But you are changing viewControllers view property, that is set by storyboard. If you want to change your view controllers view you can use,
- (void)loadView
// inside this method you can assign new view to view property.
If you are adding view as subview use view's method
- (void)addSubview:(UIView *)view