Question

I read this tutorial about storyboards on iphone dev. The guy changes views through a button. But the connection of the button is made through the interface builder. How can i do this programmatically, so i can make some checks (username/password for example) before the view is changed?
Thanks in advance.

Answer 1

Connect one view with other (not the button with the view).
Change the segue to custom and give it an identifier (in IB). Ex: Login

Then create an action and assign it to the button.

In the button action use:

[self performSegueWithIdentifier:@"Login" sender:self];

Create a Segue Class object and in the .m use something like:

UIViewController *dst = [self destinationViewController];
UIViewController *nav = [self sourceViewController];

//All your custom code

[nav presentModalViewController:dst animated:YES];

Edit: Forgot something important!

In IB, in the Segue configuratión, put in Segue Class, the name of the Segue Class created. Ex: LoginSegue is the name of the segue created, in Segue Class yo has to write “LoginSegue”

Edit: To Create the Class:

1.- Create a New File extending UIStoryBoardSegue, the .h gonna be something like:

#import <Foundation/Foundation.h>

@interface LoginSegue : UIStoryboardSegue

@end

2.- In the implementation, use the code above inside an method called perform:

-(void)perform
{

UIViewController *dst = [self destinationViewController];
UIViewController *nav = [self sourceViewController];

 //Custom Code

 [nav presentModalViewController:dst animated:YES];

}

If you need to access the property of the source viewController, you need to change:

UIViewController *nav = [self sourceViewController];

to

eYourClass *nav = [self sourceViewController];

Hope this help!