IOS 旋转+缩放(手势识别)

@interface NJViewController ()<UIGestureRecognizerDelegate>
@property (weak, nonatomic) IBOutlet UIImageView *iconView;

@end

@implementation NJViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    [self pichTest];
    [self rotationTest];
}

// 该方法返回的BOOL值决定了view是否能够同时响应多个手势
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    NSLog(@"%@ - %@", gestureRecognizer.class, otherGestureRecognizer.class);
    return YES;
}

- (void)pichTest
{
    // 捏合手势
    UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizer alloc] init];
    pinch.delegate = self;

    [self.iconView addGestureRecognizer:pinch];
    [pinch addTarget:self action:@selector(pinchView:)];
}

- (void)pinchView:(UIPinchGestureRecognizer *)pinch
{
//    NSLog(@"捏合事件 %.1f", pinch.scale);
//    self.iconView.transform = CGAffineTransformMakeScale(pinch.scale, pinch.scale);
    // 1.0 * 0.9
    self.iconView.transform = CGAffineTransformScale(self.iconView.transform, pinch.scale, pinch.scale);

    pinch.scale = 1.0;
}

- (void)rotationTest
{
    // 旋转
    UIRotationGestureRecognizer *gesture = [[UIRotationGestureRecognizer alloc] init];
    gesture.delegate = self;

    [self.iconView addGestureRecognizer:gesture];
    [gesture addTarget:self action:@selector(rotationView:)];
}

- (void)rotationView:(UIRotationGestureRecognizer *)gesture
{
//    NSLog(@"旋转事件 %.1f", gesture.rotation);

//    每次从最初的位置开始
//    self.iconView.transform = CGAffineTransformMakeRotation(gesture.rotation);

//    在传入的transform基础上递增一个弧度
    self.iconView.transform = CGAffineTransformRotate(self.iconView.transform, gesture.rotation);
    // 将旋转的弧度清零(注意不是将图片旋转的弧度清零, 而是将当前手指旋转的弧度清零)
    gesture.rotation = ;// 如果理解不了 , 记住就OK
}