Question

I’m still quite new to Xcode etc, so Im a bit fuzzy when it comes do creating/using objects in Xcode.

For example, I used a tutorial for creating a GestureRecognizer in code – it’s pretty simple.

Right now I have only this in my .h:

@interface PlayPage : UIViewController <UIGestureRecognizerDelegate>

And this in my .m:

UITapGestureRecognizer *tapTwo=[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doubleTap)];
[tapTwo setDelegate:self];
[tapTwo setNumberOfTapsRequired:2];
[tapTwo setNumberOfTouchesRequired:1];
[self.view addGestureRecognizer:tapTwo]; //adds it to view

Here are my question(s):

1) If I also want to see the GestureRecognizer in IB along with the above code (perhaps so I can change some settings since I’m not familiar with everything) how do I accomplish that?

2) How would you decide when to use all code vs. a mix of code/IB ? Is it strictly a matter of style/comfort/familiarity?

3) It seems declaring different objects requires different ‘setup’ code (UITextLabel vs GestureRecognizer vs UITextField,for example) – how do you know when to use which code?

Thanks for helping to clear this up.

Answer 1

1. In Xcode 4.x Interface builder there are UIGestureRecognizer objects that you can drag onto your views. So you would need to add the UIGestureRecognizer in Interface builder (if you need to do any more config in code then connect them up with an outlet as well).

2. I try and do anything I can in IB and drop to code when I have to but it is a matter of preference.

   • I’d rather eyeball the position of views and use the snap guides than spend a while figuring it out in code.
   • You can hide a lot of boiler plate code if you do it in IB

3. Start typing and look at the autocompletion options to jog your memory. But more importantly every time you use a class you have not used before you should at least skim the documentation to see what is suggested. Half of the questions on this site could easily be solved if the question poster actually bothered to look at the vast documentation available.

---

Update

You need to create the UIGestureRecognizer in Interface Builder not your code.

In Interface Builder ensure that the Utilities pain is visible and drag and drop a UIGestureRecognizer of the required class onto your view

This is what the UIGestureRecognizer class look like:

You then configure the object in the Utilities panel. If you want to be able to access this object in your code then you will need an IBOutlet.

In your classes header file add a new ivar for this

@property (nonatomic, retain) IBOutlet UITapGestureRecognizer *tapGestureRecognizer;

In the implementation file synthesize this

@synthesize tapGestureRecognizer = _tapGestureRecognizer;

Then back in Interface builder connect this up by ctrl + click + dragging from the File's Owner to the UIGestureRecognizer subclass. Then selecting your ivar from the window that appears: