手势操作

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;
}

UISwipeGestureRecognizer轻扫, 手指按下然后在屏幕上滑动

轻扫分四个方向（上下左右），并且如果要在一个控件上同时添加一个以上的轻扫动作，必须对每个动作添加一个对象。也就是说每个方向的动作对应一个对象。

direction: 指定轻扫动作的方向

typedef NS_OPTIONS(NSUInteger, UISwipeGestureRecognizerDirection) {
UISwipeGestureRecognizerDirectionRight = 1 << 0, // 从左向右
UISwipeGestureRecognizerDirectionLeft  = 1 << 1, // 从右向左
UISwipeGestureRecognizerDirectionUp    = 1 << 2, // 从下往上
UISwipeGestureRecognizerDirectionDown  = 1 << 3  // 从上往下
};

UISwipeGestureRecognizer *swipeUp = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipe:)];

// 设置代理
swipeUp.delegate = self;

// 修改方向, 从下往上
swipeUp.direction = UISwipeGestureRecognizerDirectionUp;

[self.image addGestureRecognizer:swipeUp];

// 添加其他方向手势
UISwipeGestureRecognizer *swipeDown = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipe:)];

// 修改方向, 从下往上
swipeDown.direction = UISwipeGestureRecognizerDirectionDown;

[self.image addGestureRecognizer:swipeDown];

UIPanGestureRecognizer拖拽，按下拖动控件操作

注意点：手势的触摸点locationInView和手势的移动点translationInView是不一样的，前者是用locationInView取得是指手指在当前控件中的坐标，后者表示相对于父view的rect

UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(pan:)];

// 设置代理
pan.delegate = self;

[self.image addGestureRecognizer:pan];

// 手势的触摸点
// CGPoint p = [pan locationInView:self.image];

// 手势的移动点(每次移动的位移点)
CGPoint transP = [pan translationInView:self.image];

NSLog(@"%f, %f", transP.x, transP.y);

self.image.transform = CGAffineTransformTranslate(self.image.transform, transP.x, transP.y);

// 复位
[pan setTranslation:CGPointZero inView:self.image];