手势

手势包括：

• 拖拽 (pan)
• 划屏 (swipe)
• 旋转 (rotate)
• 捏合 (pinch)
• 点击 (tap)
• 长按 (long press)

Xcode自带模拟器模拟2个手指时，需要按住Option，配合触控板（鼠标）使用。

添加手势

通过给view addGestureRecognizer来添加一个手势

1.划屏

self.swipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self                                                action:@selector(handleSwipes:)];self.swipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionRight;//向右滑动触发handleSwipes方法self.swipeGestureRecognizer.numberOfTouchesRequired = 1;//一个手指[self.view addGestureRecognizer:self.swipeGestureRecognizer];

handleSwipes

- (void)handleSwipes: (UISwipeGestureRecognizer *)sender {    if (sender.direction == UISwipeGestureRecognizerDirectionDown) {        NSLog(@"Swip down");    } else if (sender.direction == UISwipeGestureRecognizerDirectionUp) {        NSLog(@"Swip up");    } else if (sender.direction == UISwipeGestureRecognizerDirectionLeft) {        NSLog(@"Swip left");    } else if (sender.direction == UISwipeGestureRecognizerDirectionRight) {        NSLog(@"Swip right");    }}

2.旋转

self.rotationGestureRecongnizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self                                                action:@selector(handleRotation:)];[self.view addGestureRecognizer:_rotationGestureRecongnizer];

handleRotation

- (void)handleRotation: (UIRotationGestureRecognizer *)sender {    _imageView.transform = CGAffineTransformMakeRotation(self.rotationAngleInRadians + sender.rotation);    if (sender.state == UIGestureRecognizerStateEnded) {        self.rotationAngleInRadians += sender.rotation;    }}

rotationAngleInRadians是自定义的property

拖拽

_panGestureRecongizer = [[UIPanGestureRecognizer alloc] initWithTarget:self                                                action:@selector(handlePan:)];[self.view addGestureRecognizer:_panGestureRecongizer];

handlePan

- (void)handlePan: (UIPanGestureRecognizer *)sender {    if (sender.state != UIGestureRecognizerStateEnded && sender.state != UIGestureRecognizerStateFailed) {        CGPoint location = [sender locationInView:sender.view.superview];        self.imageView.center = location;//更新位置    }}

捏合

_pinchGestrueRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self                                                action:@selector(handlePinches:)];[self.view addGestureRecognizer:_pinchGestrueRecognizer];

handlePinches

- (void)handlePinches:(UIPinchGestureRecognizer *)sender {    if (sender.state == UIGestureRecognizerStateEnded) {        _currentScale = sender.scale;    } else if (sender.state == UIGestureRecognizerStateBegan && _currentScale != 0.0f) {        sender.scale = _currentScale;    }    if (sender.scale != NAN && _currentScale != 0.0f) {        sender.view.transform = CGAffineTransformMakeScale(sender.scale, sender.scale);//更新图像    }}

点击

_tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self                                                action:@selector(handleTap:)];_tapGestureRecognizer.numberOfTouchesRequired = 2;//需要2个手指才有效_tapGestureRecognizer.numberOfTapsRequired = 3;//需要点击3下[self.view addGestureRecognizer:_tapGestureRecognizer];

handleTap

- (void)handleTap: (UITapGestureRecognizer *)sender {    for (NSUInteger touchCount = 0; touchCount < _tapGestureRecognizer.numberOfTouchesRequired; touchCount++) {        CGPoint touchPoint = [sender locationOfTouch:touchCount inView:sender.view];        NSLog(@"Touch %lu, %@", touchCount + 1, NSStringFromCGPoint(touchPoint));    }}

长按

_longGestureRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self                                                action:@selector(handleLongpresses:)];_longGestureRecognizer.numberOfTouchesRequired = 2;//需要2个手指_longGestureRecognizer.allowableMovement = 100;_longGestureRecognizer.minimumPressDuration = 1.0;//最少按1s[self.view addGestureRecognizer:_longGestureRecognizer];

handleLongpresses

- (void)handleLongpresses: (UILongPressGestureRecognizer *)sender {    if ([sender isEqual:_longGestureRecognizer]) {        if (sender.numberOfTouchesRequired == _longGestureRecognizer.numberOfTouchesRequired) {            CGPoint touchPoint1 = [sender locationOfTouch:0 inView:sender.view];            CGPoint touchPoint2 = [sender locationOfTouch:1 inView:sender.view];            CGFloat midPointX = (touchPoint1.x + touchPoint2.x) / 2.0;            CGFloat midPointY = (touchPoint1.y + touchPoint2.y) / 2.0;            CGPoint midPoint = CGPointMake(midPointX, midPointY);            _imageView.center = midPoint;//更新位置        } else {            NSLog(@"Long press, fingers' not right");        }    }}

效果