trying to make a button spin in Xcode with 6.3.2 objective-C - xcode6

Question

I watched a video on how to make a button spin in Objective-C. I entered all the code exactly like in video except I got some syntex errors/ "!". I am very new to Xcode and only know some of the basics to javascript. Please help have been trying to figure this out for too long.
This is what I did in ViewController.h:
// ViewController.h
#import <UIKit/UIKit.h>
#import <QuartzCore/QuartzCore.h>
#import <AVFoundation/AVFoundation.h>
This part in the code I get "!", it doesn't seem to like the "()". when I take that part out it's fine but the button doesn't seem to be recognized when it is called later on in ViewController.m. I'll explain what each "!" says to the write of the code where I'm getting each error. to separate it from the code ill put 2 "//" next to it.
#interface ViewController : UIViewController( // ! Method type specifier must start with '-' or '+'
I get 3 error messages on this next line of code.
IBOutlet UIButton *button; //! IBOutlet attribute ignored when parsing type, Expected selector for Objective-C method, and Expected ')'
) //! Expected identifier or '('
- (IBAction)spin:(id)sender;
#end
Now here's what I did in ViewController.m
// ViewController.m
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)spin:(id)sender {
CABasicAnimation *fullRotation = [CABasicAnimation
animationWithKeyPath:#"transform.rotate" ];
fullRotation.fromValue = [NSNumber numberWithFloat:0];
fullRotation.toValue = [NSNumber numberWithFloat:((360*M_PI)/180)];
fullRotation.duration = 2.0;
fullRotation.repeatCount = 300;
in this part of the code I get the "!" again no matter what I do to change it
[button.layer addAnimation:fullRotation forKey:#"360"]; //! Use of undeclared identifier 'button'
}
#end

Answer 1

UIViewController( should not have the ( on the end.

Answer 2

just use:
// ViewController.h
#interface ViewController : UIViewController
#property(nonatomic, weak) UIButton *button;
- (IBAction)spin:(id)sender;
It's recommended to use #property since it generates getter/setter and you can set weak reference.
and in the implementation file add self.
[self.button.layer addAnimation:fullRotation forKey:#"360"]