IOS手势识别，捏合，旋转，轻扫等

//点按手势的创建，这里需要实现响应事件的方法
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tap)];

tap.delegate = self;
//  添加到需要手势的视图
[_imageView addGestureRecognizer:tap];

//长按手势的创建
// 长按手势时间比较长，可以根据手势的状态states，设置功能；
UILongPressGestureRecognizer*longPres = [[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(longPress:)];

[_imageView addGestureRecognizer:longPres];

// 添加轻扫手势，轻扫默认的方向：向右
//一个轻扫手势只能支持一个方向
//一个控件可以添加很多手势
UISwipeGestureRecognizer*swipeLeft = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
    //在响应方法中，可以根据轻扫的方向（direction）做事情；
//这是一个枚举类型，上下左右；
swipeLeft.direction=
UISwipeGestureRecognizerDirectionLeft;
[_imageView addGestureRecognizer:swipeLeft];
   
UISwipeGestureRecognizer*swipeRight = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
   
swipeRight.direction=
UISwipeGestureRecognizerDirectionRight;
[_imageView addGestureRecognizer:swipeRight];

//拖拽手势的创建
UIPanGestureRecognizer*pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(pan:)];

[_imageView addGestureRecognizer:pan];

- (void)pan:(UIPanGestureRecognizer*)pan

{

    //
获取手指偏移量，相对于最原始位置的偏移量
   CGPoint
transP = [pantranslationInView:_imageView];
   //
改imageView形变
   _imageView.transform=
CGAffineTransformTranslate(_imageView.transform, transP.x,
transP.y);
   //
复位，相对于上一次
    [pansetTranslation:CGPointZeroinView:_imageView];
}

//在使用模拟器模拟一下两个手势的时候，需要按住option + 鼠标左键实现两个手指点击（反向运动）；shift + option + 鼠标左键（同向运动）；

//旋转手势的创建
UIRotationGestureRecognizer*rotation = [[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(rotation:)];
rotation.delegate=
self;
[_imageView addGestureRecognizer:rotation];

//方法的实现
- (void)rotation:(UIRotationGestureRecognizer*)rotationGestureRecognizer
{
   _imageView.transform=
CGAffineTransformRotate(_imageView.transform,
rotationGestureRecognizer.rotation);
   //
复位
    rotationGestureRecognizer.rotation = 0;
}

//捏合缩放手势的实现
UIPinchGestureRecognizer*pinch = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(pinch:)];

pinch.delegate=
self;
[_imageView addGestureRecognizer:pinch];

//响应方法的实现
- (void)pinch:(UIPinchGestureRecognizer*)pinch

{

    //
获取相对于最原始的缩放比例
   CGFloat
scale = pinch.scale;
    // x,y，x表示宽度缩放多少，y表示高度缩放
   _imageView.transform=
CGAffineTransformScale(_imageView.transform,
scale, scale);

    //
复位
    pinch.scale = 1; 
}

手势代理方法的实现：
//当View需要同时实现多个手势的时候。需要返回YES；
- (BOOL)gestureRecognizer:(UIGestureRecognizer*)gestureRecognizer
shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer*)otherGestureRecognizer;

//可以控制点击区域是否实现手势；通过UITouch获取当前点击的点，通过坐标控制区域
- (BOOL)gestureRecognizer:(UIGestureRecognizer*)gestureRecognizer shouldReceiveTouch:(UITouch*)touch;