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
UITapGestureRecognizer(敲击)
UIPinchGestureRecognizer(捏合，用于缩放)
UIPanGestureRecognizer(拖拽)
UISwipeGestureRecognizer(轻扫)
UIRotationGestureRecognizer(旋转)
UILongPressGestureRecognizer(长按)
使用方法
// 创建点按手势
UITapGestureRecognizer *gesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tap:)];
// 给imageView添加手势，默认imageView不响应事件
// 设置imageView 响应事件
self.imageView.userInteractionEnabled = YES;
[self.imageView addGestureRecognizer:gesture];
响应手势事件，可以在里面进行形变
// 响应手势事件
- (void)tap:(UITapGestureRecognizer *)tap
{
NSLog(@"%s",__func__);
// 旋转
self.imageView.transform = CGAffineTransformRotate(self.imageView.transform, M_PI_4);
}
手势的状态
typedef NS_ENUM(NSInteger, UIGestureRecognizerState) {
// 没有触摸事件发生，所有手势识别的默认状态
UIGestureRecognizerStatePossible,
// 一个手势已经开始但尚未改变或者完成时
UIGestureRecognizerStateBegan,
// 手势状态改变
UIGestureRecognizerStateChanged,
// 手势完成
UIGestureRecognizerStateEnded,
// 手势取消，恢复至Possible状态
UIGestureRecognizerStateCancelled,
// 手势失败，恢复至Possible状态
UIGestureRecognizerStateFailed,
// 识别到手势识别
UIGestureRecognizerStateRecognized = UIGestureRecognizerStateEnded
};
手势的一些代理方法
#pragma mark - 手势代理方法
// 是否开始手势
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
return YES;
}
//是否允许同时支持多个手势，默认是不支持多个手势
// 返回yes表示支持多个手势
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}
// 是否允许接收手指的触摸点
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
// NSLog(@"%@",touch);
return YES;
}
逐个实现每个手势
1、点按 UITapGestureRecognizer
#pragma mark - 各种手势
// UITapGestureRecognizer
// 点按
- (void)tapImage
{
// 创建点按手势
UITapGestureRecognizer *gestur = [[UITapGestureRecognizeralloc] initWithTarget:selfaction:@selector(tap:)];
// 给imageView添加手势，默认imageView不响应事件
gestur.delegate = self;
gestur.numberOfTapsRequired = 2; // 点击次数
[self.imageView addGestureRecognizer:gestur];
}
// 响应点按手势事件
- (void)tap:(UITapGestureRecognizer *)tap
{
// 连续点按两次就更换显示图片
if (tap.numberOfTapsRequired == 2) {
self.imageView.image = [UIImage imageNamed:@"qianbao"];
}
}
2、捏合 可以使用两个手指进行缩放 UIPinchGestureRecognizer
//UIPinchGestureRecognizer
// 捏合，可以缩放
- (void)pinchImage
{
UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizeralloc] initWithTarget:selfaction:@selector(pinch:)];
//pinch.delegate = self;
[self.imageViewaddGestureRecognizer:pinch];
}
- (void)pinch:(UIPinchGestureRecognizer *)pinch
{
self.imageView.transform = CGAffineTransformScale(self.imageView.transform, pinch.scale,pinch.scale);
// 复位
pinch.scale = 1;
}
3、长按 UILongPressGestureRecognizer
// UILongPressGestureRecognizer
// 长按,默认会触发两次,开始时调用一次，结束时调用一次，可以根据手势状态
- (void)longPressImage
{
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizeralloc] initWithTarget:selfaction:@selector(longPress:)];
[self.imageView addGestureRecognizer:longPress];
}
- (void)longPress:(UILongPressGestureRecognizer *)longP
{
// 判断手势状态，只在手势开始的时候执行。
if(longP.state == UIGestureRecognizerStateBegan)
{
self.imageView.transform = CGAffineTransformRotate(self.imageView.transform, M_PI);
}
}
4、清扫 轻轻向某个方向滑动
// UISwipeGestureRecognizer
// 清扫手势，默认向右
- (void)swipeImage
{
UISwipeGestureRecognizer *swipe = [[UISwipeGestureRecognizeralloc] initWithTarget:selfaction:@selector(swipe:)];
[self.imageViewaddGestureRecognizer:swipe];
// 如果以后想要一个控件支持多个方向的轻扫，必须创建多个轻扫手势，一个轻扫手势只支持一个方向
// 默认轻扫的方向是往右
UISwipeGestureRecognizer *swipeUp = [[UISwipeGestureRecognizeralloc] initWithTarget:selfaction:@selector(swipe:)];
swipeUp.direction = UISwipeGestureRecognizerDirectionUp;
[self.imageView addGestureRecognizer:swipeUp];
}
- (void)swipe:(UISwipeGestureRecognizer *)swipe
{
// 输出状态
NSLog(@"%s\n%ld",__func__,swipe.direction);
}
5、旋转 UIRotationGestureRecognizer
// UIRotationGestureRecognizer
// 旋转手势
- (void)rotateImage
{
UIRotationGestureRecognizer *rotate = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotate:)];
[self.imageView addGestureRecognizer:rotate];
}
- (void)rotate:(UIRotationGestureRecognizer *)rotate
{
self.imageView.transform = CGAffineTransformRotate(self.imageView.transform, rotate.rotation);
// 复位
rotate.rotation = 0;
}
6、拖拽 UIPanGestureRecognizer
// 拖拽
- (void)panImage
{
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizeralloc] initWithTarget:selfaction:@selector(pan:)];
[self.imageViewaddGestureRecognizer:pan];
}
- (void)pan:(UIPanGestureRecognizer *)pan
{
// 获取手势移动点
CGPoint curP = [pan translationInView:self.imageView];
self.imageView.transform = CGAffineTransformTranslate(self.imageView.transform, curP.x, curP.y);
// 复位,一定要复位
[pan setTranslation:CGPointZeroinView:self.imageView];
}
在视图加载时进行调用即可
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
// 设置imageView 响应事件
self.imageView.userInteractionEnabled = YES;
// 点按图形
[self tapImage];
// 长按
[selflongPressImage];
// 清扫
[self swipeImage];
// 旋转
[self rotateImage];
// 缩放
[self pinchImage];
// 拖拽
// [self panImage];
}
简单效果如下
