iOS手势操作总结
手势操作种类
UITapGestureRecognizer: 敲击，点击 UILongPressGestureRecognizer: 长按 UIPinchGestureRecognizer: 缩放 UIRotationGestureRecognizer: 旋转 UISwipeGestureRecongizer: 轻扫 UIPanGestureRecognizer: 拖拽手势操作的代理方法(UIGestureRecognizerDelegate)
手势可能发生的条件，返回NO可以阻止此手势的发生或者此手势不产生任何效果
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer;
是否允许多个手势同时发生
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)
gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:
(UIGestureRecognizer *)otherGestureRecognizer;
UITapGestureRecognier敲击，点击手势
设置属性numberOfTapsRequired可以指定需要几根手指才能触发事件 numberOfTouchesRequired：可以设置需要敲击几次触发事件
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tap:)];
// 设置代理
tap.delegate = self;
// 设置点击次数触发手势事件
tap.numberOfTapsRequired = 1;
// 设置需要点击的手指数
tap.numberOfTouchesRequired = 1;
[self.image addGestureRecognizer:tap];
UILongPressGestureRecongnizer长按
minimumPressDuration设置长按的最小间隔时间，也就是说按下开始和手指离开时的中间间隔，如果小于这个值则不会被认为是长按操作 allowableMovement：长按过程中是否允许移动
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)];
// 代理
longPress.delegate = self;
// 设置最小间隔时间, 手指按下与离开间隔时间
longPress.minimumPressDuration = 1.0;
// 按下过程中允许移动的像素
longPress.allowableMovement = 30;
[self.image addGestureRecognizer:longPress];
UIPinchGestureRecognizer缩放手势
scale: 设置缩放比例，相对于原来大小
UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinch:)];
// 代理
pinch.delegate = self;
// 设置缩放比例
pinch.scale = 1.2;
[self.image addGestureRecognizer:pinch];
UIRotationGestureRecognizer旋转手势
rotation: 旋转弧度，要保证每次都在上一次位置开始旋转，而不是回归初始位置，必须要在动作方法里将此值清零
- (void)setupRotation
{
UIRotationGestureRecognizer *rotation = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotation:)];
// 设置代理
rotation.delegate = self;
[self.image addGestureRecognizer:rotation];
}
- (void)rotation:(UIRotationGestureRecognizer *)rotation
{
// 旋转角度
CGFloat radian = rotation.rotation;
self.image.transform = CGAffineTransformRotate(self.image.transform, radian);
// 复位，保证每次都是在上一次位置开始转，而不是每次都回归初始位置再转
rotation.rotation = 0;
}
