UIGestureRecognizer
为了完成手势识别，必须借助于手势识别器—-UIGestureRecognizer，利用UIGestureRecognizer，能轻松识别用户在某个view上面做的一些常见手势UIGestureRecognizer是一个抽象类，定义了所有手势的基本行为，使用它的子类才能处理具体的手势，要实现<UIGestureRecognizerDelegate>
手势状态：
typedef NS_ENUM(NSInteger, UIGestureRecognizerState) { UIGestureRecognizerStatePossible, // 尚未识别是何种手势操作（但可能已经触发了触摸事件），默认状态 UIGestureRecognizerStateBegan, // 手势已经开始，此时已经被识别，但是这个过程中可能发生变化，手势操作尚未完成 UIGestureRecognizerStateChanged, // 手势状态发生转变 UIGestureRecognizerStateEnded, // 手势识别操作完成（此时已经松开手指） UIGestureRecognizerStateCancelled, // 手势被取消，恢复到默认状态 UIGestureRecognizerStateFailed, // 手势识别失败，恢复到默认状态 UIGestureRecognizerStateRecognized = UIGestureRecognizerStateEnded // 手势识别完成，同UIGestureRecognizerStateEnded };
常用的六种手势：
- 轻击手势（TapGestureRecognizer）
- 轻扫手势 （SwipeGestureRecognizer）
- 长按手势（LongPressGestureRecognizer）
- 拖动手势（PanGestureRecognizer）
- 捏合手势（PinchGestureRecognizer）
- 旋转手势（RotationGestureRecognizer）
1． 轻击手势（TapGestureRecognizer）
1) 初始化轻击手势识别器对象 UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] init]; 2) 设置手势识别器对象的具体属性 // 连续敲击2次 tap.numberOfTapsRequired = 2; // 需要2根手指一起敲击 tap.numberOfTouchesRequired = 2; //添加手势识别器到对应的view上 [self.iconView addGestureRecognizer:tap]; 3) 监听手势的触发 [tap addTarget:self action:@selector(tapIconView:)]; 4) 代理 tap.delegate = self; //轻击手势触发方法 -(void) tapIconView:(UITapGestureRecognizer *)sender { NSLog(@"我用两只手指敲击屏幕成功了！"); } #pragma mark - 代理方法 /** * 当点击view的时候,会先调用这个方法 */ - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch { CGPoint pos = [touch locationInView:touch.view]; if (pos.x <= self.iconView.frame.size.width * 0.5) { return YES; } return NO; }
2． 轻扫手势 （SwipeGestureRecognizer）
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初始化轻扫手势识别器对象 UISwipeGestureRecognizer *swipeGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeGesture:)]; //设置轻扫的向右方向 swipeGesture.direction = UISwipeGestureRecognizerDirectionRight; //向右 [self.view addGestureRecognizer:swipeGesture]; UISwipeGestureRecognizer *swipeGestureLeft = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeGesture:)]; //设置轻扫的方向 swipeGestureLeft.direction = UISwipeGestureRecognizerDirectionLeft; //向左 [self.view addGestureRecognizer:swipeGestureLeft]; //轻扫手势触发方法 -(void)swipeGesture:(id)sender { UISwipeGestureRecognizer *swipe = sender; if (swipe.direction == UISwipeGestureRecognizerDirectionLeft) { //向左轻扫 } if (swipe.direction == UISwipeGestureRecognizerDirectionRight) { //向右轻扫 } }
3． 长按手势（LongPressGestureRecognizer）
初始化轻扫手势识别器对象 UILongPressGestureRecognizer *longPressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressGesture:)]; //设置长按时间 longPressGesture.minimumPressDuration = 0.5; [self.view addGestureRecognizer:longPressGesture]; //长按手势触发方法 -(void)longPressGesture:(id)sender { UILongPressGestureRecognizer *longPress = sender; if (longPress.state == UIGestureRecognizerStateBegan) { //your code } } 说明：长按手势的常用状态如下 开始：UIGestureRecognizerStateBegan 改变：UIGestureRecognizerStateChanged 结束：UIGestureRecognizerStateEnded 取消：UIGestureRecognizerStateCancelled 失败：UIGestureRecognizerStateFailed
4． 拖动手势（PanGestureRecognizer）
初始化轻扫手势识别器对象 UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGesture:)]; [self.view addGestureRecognizer:panGesture]; //拖动手势触发方法 -(void) panGesture:(id)sender { UIPanGestureRecognizer *panGesture = sender; CGPoint movePoint = [panGesture translationInView:self.view]; //your code }
5． 捏合手势（PinchGestureRecognizer）
初始化轻扫手势识别器对象 UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGesture:)]; [self.view addGestureRecognizer:panGesture]; //拖动手势触发方法 -(void) panGesture:(id)sender { UIPanGestureRecognizer *panGesture = sender; CGPoint movePoint = [panGesture translationInView:self.view]; //your code }
6． 旋转手势（RotationGestureRecognizer）
初始化轻扫手势识别器对象 UIRotationGestureRecognizer *rotationGesture = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotationGesture:)]; [self.view addGestureRecognizer:rotationGesture]; //旋转手势触发方法 -(void)rotationGesture:(id)sender { UIRotationGestureRecognizer *gesture = sender; if (gesture.state==UIGestureRecognizerStateChanged) { _imageView.transform=CGAffineTransformMakeRotation(gesture.rotation); } if(gesture.state==UIGestureRecognizerStateEnded) { [UIView animateWithDuration:1 animations:^{ _imageView.transform=CGAffineTransformIdentity;//取消形变 }]; } }