How to programmatically call a view controller?

Question

I have looked through all the training materials that I can find on this and I still have no answer. I need to call another view from code. I am using UIStoryboards . I changed the view several times by dragging a control from UIButtons , but now it should be from code. I am trying to call up the information page from the main menu if this is the first time the user has opened the application. However, I cannot find a way to change the views from the code. All my views are controlled by the same files ( ViewController2 ). identifier my main menu is ViewControllerMain , and the identifier information page is ViewControllerInfo . First I tried this:

 [ViewControllerMain presentViewController: ViewControllerInfo animated:YES completion: NULL]; 

Then I tried to make different UIViewControllers for each and say:

 [ViewController2 presentViewController: ViewController animated:YES completion: NULL]; 

None of them worked. For the first, he says:

Using an undeclared ViewControllerMain identifier.

In the second, he says:

unexpected interface name "ViewController": expected identifier.

What can I do?

Answer 1

To create a view controller:

 UIViewController * vc = [[UIViewController alloc] init]; 

To call a view controller (must be called from another view manager):

 [self presentViewController:vc animated:YES completion:nil]; 

For one, use null, not null.

---

Loading the view controller from the storyboard:

 NSString * storyboardName = @"MainStoryboard"; UIStoryboard *storyboard = [UIStoryboard storyboardWithName:storyboardName bundle: nil]; UIViewController * vc = [storyboard instantiateViewControllerWithIdentifier:@"IDENTIFIER_OF_YOUR_VIEWCONTROLLER"]; [self presentViewController:vc animated:YES completion:nil]; 

Identifier identifier of your view controller is either the class name of your view controller or the storyboard identifier that you can assign in the identity inspector of your storyboard.

Answer 2

You need to create an instance of the view controller from the storyboard, and then show it:

 ViewControllerInfo* infoController = [self.storyboard instantiateViewControllerWithIdentifier:@"ViewControllerInfo"]; [self.navigationController pushViewController:infoController animated:YES]; 

This example assumes that you have a navigation controller to return to the previous view. You can, of course, also use presentViewController: animated: completion :. The main thing is that your storyboard creates your target view controller using the target view controller identifier.

Answer 3

Swift

This gets the view controller from the storyboard and presents it.

 let storyboard = UIStoryboard(name: "Main", bundle: nil) let secondViewController = storyboard.instantiateViewController(withIdentifier: "secondViewControllerId") as! SecondViewController self.present(secondViewController, animated: true, completion: nil) 

Change the name of the storyboard, the name of the controller of the controller and, if necessary, check the identifier of the controller.

Answer 4

There are two ways to do this:

1, create a segue for your ViewController in your storyboard, as described in my answer here: How to make a session not related to user input in iOS 5?

2, give your ViewController and id and call it using the code in my answer here: Programmatic script call script (no segue needed)?

Answer 5

You can call the ViewController this way if you want with the NavigationController

1. In the current screen: Loading a new screen

 VerifyExpViewController *addProjectViewController = [[VerifyExpViewController alloc] init]; [self.navigationController pushViewController:addProjectViewController animated:YES]; 

2.1 Downloaded: Add below to .h file

 @interface VerifyExpViewController : UIViewController <UINavigationControllerDelegate> 

2.2 Downloaded: Add below to the .m file

  @implementation VerifyExpViewController - (void)viewDidLoad { [super viewDidLoad]; self.navigationController.delegate = self; [self setNavigationBar]; } -(void)setNavigationBar { self.navigationController.navigationBar.backgroundColor = [UIColor clearColor]; self.navigationController.navigationBar.translucent = YES; [self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:@"B_topbar.png"] forBarMetrics:UIBarMetricsDefault]; self.navigationController.navigationBar.titleTextAttributes = @{NSForegroundColorAttributeName: [UIColor whiteColor]}; self.navigationItem.hidesBackButton = YES; self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"Btn_topback.png"] style:UIBarButtonItemStylePlain target:self action:@selector(onBackButtonTap:)]; self.navigationItem.leftBarButtonItem.tintColor = [UIColor lightGrayColor]; self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"Save.png"] style:UIBarButtonItemStylePlain target:self action:@selector(onSaveButtonTap:)]; self.navigationItem.rightBarButtonItem.tintColor = [UIColor lightGrayColor]; } -(void)onBackButtonTap:(id)sender { [self.navigationController popViewControllerAnimated:YES]; } -(IBAction)onSaveButtonTap:(id)sender { //todo for save button } @end 

Hope this will be helpful to someone out there :)

Answer 6

The basic logic of this is: _,

 NSString * storyboardIdentifier = @"SecondStoryBoard"; UIStoryboard *storyboard = [UIStoryboard storyboardWithName:storyboardIdentifier bundle: nil]; UIViewController * UIVC = [storyboard instantiateViewControllerWithIdentifier:@"YourviewControllerIdentifer"]; [self presentViewController:UIVC animated:YES completion:nil]; 

Answer 7

Import the view controller class you want to show and use the following code

 KartViewController *viewKart = [[KartViewController alloc]initWithNibName:@"KartViewController" bundle:nil]; [self presentViewController:viewKart animated:YES completion:nil]; 

Answer 8

  UIStoryboard* storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard_iPhone_iOS7" bundle:nil]; AccountViewController * controller = [storyboard instantiateViewControllerWithIdentifier:@"accountView"]; // [self presentViewController:controller animated:YES completion:nil]; UIViewController *topRootViewController = [UIApplication sharedApplication].keyWindow.rootViewController; while (topRootViewController.presentedViewController) { topRootViewController = topRootViewController.presentedViewController; } [topRootViewController presentViewController:controller animated:YES completion:nil];