#import "HMViewController.h"

#define angle2radian(x) ((x) / 180.0 * M_PI)

@interface HMViewController ()

@property (weak, nonatomic) IBOutlet UIImageView *imageView;

@end

@implementation HMViewController

- (void)viewDidLoad

{

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)];

    [_imageView addGestureRecognizer:longPress];

}

- (void)longPress:(UILongPressGestureRecognizer *)longPress

{

    if (longPress.state == UIGestureRecognizerStateBegan) {

        CAKeyframeAnimation *anim = [CAKeyframeAnimation animation];

        anim.keyPath = @"transform.rotation";

        anim.values = @[@(angle2radian(-)),@(angle2radian()),@(angle2radian(-))];

        anim.repeatCount = MAXFLOAT;

        anim.duration = 0.5;

        [_imageView.layer addAnimation:anim forKey:nil];

    }

}

@end