Question

In my application, I have a ViewController (ViewController 1) that has a UITextField and a UIButton. In my ViewController 2, I have a UINavigationBar. I want to be able to type something in the ViewController 1 textfield, press the button, then have the UINavigationBar text in ViewController 2 be set as the UITextField from ViewController 1. But of course, Xcode will not let you declare objects from another ViewController without doing more work. How can I do this?

Answer 1

Your question is not very clear but from what I could understand you want a ViewController‘s UIButton to set the NavigationBar‘s title of a second ViewController?

Seems like a pretty weird behavior to me but here’s what I think might help you.

On your first ViewController create a protocol/delegate functionality so that when your UIButton is pressed you can call:

-(IBAction) changeTitle:(id) sender {    
[self.delegate buttonPressed:txtView.text];
}

And with that send your UITextField‘s text to your AppDelegate, or whoever creates these two ViewControllers, and there you will receive that text and send it to your second ViewController.

-(void)buttonPressed:(NSString *)text{
secondViewController.title = text;
} 

Perhaps you will have to implement a method that changes the title in your second ViewController if that line does not work. Hope this is useful for you and that I understood your question.