Objective-C & Interface Builder for Dummies: How do I bind the keyboard?

So, I've开发者_如何学运维 been reading through other questions on here and Xcode's documentation, but I'm still a bit confused. Here's the scenario: I have a login screen for my app which has 3 text fields and 1 button. Each text field is bound to have a Return Key in IB: Next, Next, Go.

Now, how do I bind these return keys to actual actions where field 1 moves to the next, then field 2 moves to the next, and last field 3 triggers the button?

Some answers for similar questions suggest the use of textFieldShouldReturn method, but I'm still fuzzy on it. Somehow I can't see how it auto-magically knows what to do without having some kind of binding...

What you need to do is use an IBAction to select the next field when the return key is pressed. To do this, first add a method like this to your UIViewController. Make sure to add the method declaration to your header.

- (IBAction)selectSecondField:(id)sender
{
    //_secondField is the IBOutlet to the second field
    [_secondField becomeFirstResponder];
}

Build and then go to Interface Builder. Select the first text field and open the connections inspector (⌘2) and drag from the dot next to "Did End On Exit" to your controller with the action. A menu of actions will pop up, select selectSecondField.

You will need an action for each field. Alternatively, you could have one action and use sender to see which field was returned.

There's a handle (in the connections panel) on each text field called "nextfield" or something along those lines? (I can't remember off the top of my head) But if you drag that to the next box, that's how it knows (manually). I think generally it guesses using the X/Y location, but when you need to manually do it, just drag that handle.