iOS六种手势操作

在我们平时使用app的时候，会涉及到一些比较奇特的功能，比如在查看图片的时候，大部分软件我们都可以双击放大图片，包括一些按钮，它的点按和长按也会有不同的效果，对于这些要怎么实现呢？

iOS 系统在 3.2 以后，他提供了六种常用的手势（UIGestureRecognizer 的子类），开发者可以直接使用他们进行手势操作。

手势操作类型

🎇

• UIPanGestureRecognizer（拖动）
• UIPinchGestureRecognizer（捏合）
• UIRotationGestureRecognizer（旋转）
• UITapGestureRecognizer（点按）
• UILongPressGestureRecognizer（长按）
  ​- UISwipeGestureRecognizer（轻扫）

除此之外，我们还可以自定义手势，通过一个继承于UIGestureRecognizer 的子类。

手势操作状态

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};

1.轻点手势（UITapGestureRecognizer）

    //创建手势对象(轻点）UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapClick:)];//设置相关属性//点击次数（默认1）tap.numberOfTapsRequired = 1;//手指的个数（默认1）tap.numberOfTouchesRequired = 1;//添加到视图[self.testView addGestureRecognizer:tap];

//点按
- (void)tapClick:(UITapGestureRecognizer *)tap {NSLog(@"轻点手势响应！");self.view.backgroundColor = [UIColor systemPinkColor];
}

2.长按手势(UILongPressGestureRecognizer)

    //创建手势对象（长按）UILongPressGestureRecognizer *longPressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressClick:)];//设置相关属性//用几个手指触屏，默认1longPressGesture.numberOfTouchesRequired = 1;//设置最短长按时间，单位为秒（默认0.5）longPressGesture.minimumPressDuration = 1;//设置手势识别期间所允许的手势可移动范围longPressGesture.allowableMovement = 10;//添加到视图[self.testView addGestureRecognizer:longPressGesture];

//长按
- (void)longPressClick:(UILongPressGestureRecognizer *)press {//state属性是所有手势父类提供的方法，用于记录手势的状态if (press.state == UIGestureRecognizerStateBegan) {NSLog(@"长按手势开始响应!");} else if (press.state == UIGestureRecognizerStateChanged) {NSLog(@"长按手势状态发生改变!");} else {NSLog(@"长按手势结束!");}
}

3.轻扫手势(UISwipeGestureRecognizer)

    //创建手势对象（左扫）UISwipeGestureRecognizer *leftSwipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeGestureClick:)];//设置轻扫的方向leftSwipe.direction = UISwipeGestureRecognizerDirectionLeft;//添加到视图[self.testView addGestureRecognizer:leftSwipe];//右扫UISwipeGestureRecognizer *rightSwipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeGestureClick:)];rightSwipe.direction = UISwipeGestureRecognizerDirectionRight;[self.testView addGestureRecognizer:rightSwipe];

//轻扫
-(void)swipeGestureClick:(UISwipeGestureRecognizer *)swpie{//如果是左扫if (swpie.direction == UISwipeGestureRecognizerDirectionLeft ) {self.view.backgroundColor = [UIColor blueColor];NSLog(@"左扫!");} else {self.view.backgroundColor = [UIColor grayColor];NSLog(@"右扫!");}
}

4.平移手势(UIPanGestureRecognizer)

    //创建手势对象(平移)UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGestureClick:)];//添加到视图[self.testView addGestureRecognizer:panGesture];

//平移
- (void)panGestureClick:(UIPanGestureRecognizer *)pan {NSLog(@"响应！！");//通过pan手势，能够获取到pan.view在self.view上的偏移量CGPoint point = [pan translationInView:self.view];NSLog(@"x=%.2lf y=%.2lf",point.x,point.y);//改变中心点坐标（原来的中心点+偏移量=当前的中心点）CGPoint newCenter = CGPointMake(pan.view.center.x + point.x, pan.view.center.y + point.y);//CGPointZero<==>CGPointMake(0,0)//限制拖动范围newCenter.y = MAX(pan.view.frame.size.height/2, newCenter.y);newCenter.y = MIN(self.view.frame.size.height - pan.view.frame.size.height/2,  newCenter.y);newCenter.x = MAX(pan.view.frame.size.width/2, newCenter.x);newCenter.x = MIN(self.view.frame.size.width - pan.view.frame.size.width/2, newCenter.x);pan.view.center = newCenter;//每次调用之后，需要重置手势的偏移量，否则偏移量会自动累加[pan setTranslation:CGPointZero inView:self.view];
}

5.捏合手势(UIPinchGestureRecognizer)

    //创建手势对象(捏合)UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pichGestureClick:)];//添加到视图[self.testView addGestureRecognizer:pinchGesture];

//捏合
- (void)pichGestureClick:(UIPinchGestureRecognizer *)pinch {//缩放的系数NSLog(@"%.2lf", pinch.scale);//固定写法pinch.view.transform = CGAffineTransformScale(pinch.view.transform, pinch.scale, pinch.scale);//重置缩放系数（否则系数会累加）pinch.scale = 1.0;
}

6.旋转手势(UIRotationGestureRecognizer)

    //创建手势对象（旋转）UIRotationGestureRecognizer *rotationGesture = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotationGestureClick:)];//添加到视图[self.testView addGestureRecognizer:rotationGesture];

//旋转
- (void)rotationGestureClick:(UIRotationGestureRecognizer *)rotation {//rotation.rotation 手势旋转的角度rotation.view.transform = CGAffineTransformRotate(rotation.view.transform, rotation.rotation);//重置角度rotation.rotation = 20;
}

在之前看到安卓组同学写项目的时候用到了，一个左侧抽屉视图，在iOS中我尝试去找怎么写抽屉视图，查到的资料有用到第三方库的方法，但是这个方法讲的有些抽象，并没有太理解，经过学长的指导，这个抽屉视图用到的方法就是手势操作和动画之间的操作，通过平移操作来完成这一视图。