IOS手势操作（拖动、捏合、旋转、点按、长按、轻扫、自定义）

下面通过图文并茂的方式给大家分享下ios手势操作（拖动、捏合、旋转、点按、长按、轻扫、自定义）的相关内容。

1、uigesturerecognizer 介绍
手势识别在 ios 中非常重要，他极大地提高了移动设备的使用便捷性。

ios 系统在 3.2 以后，他提供了一些常用的手势（uigesturerecognizer 的子类），开发者可以直接使用他们进行手势操作。

uipangesturerecognizer（拖动）

uipinchgesturerecognizer（捏合）

uirotationgesturerecognizer（旋转）

uitapgesturerecognizer（点按）

uilongpressgesturerecognizer（长按）

​uiswipegesturerecognizer（轻扫）

另外，可以通过继承 uigesturerecognizer 类，实现自定义手势（手势识别器类）。

ps：自定义手势时，需要 #import <uikit/uigesturerecognizersubclass.h>，一般需实现如下方法：

- (void)reset;

- (void)touchesbegan:(nsset *)touches withevent:(uievent *)event;
- (void)touchesmoved:(nsset *)touches withevent:(uievent *)event;
- (void)touchesended:(nsset *)touches withevent:(uievent *)event;
- (void)touchescancelled:(nsset *)touches withevent:(uievent *)event;
//以上方法在分类 uigesturerecognizer (uigesturerecognizerprotected) 中声明，更多方法声明请自行查看

uigesturerecognizer 的继承关系如下：

2、手势状态
在六种手势识别中，只有一种手势是离散型手势，他就是 uitapgesturerecognizer。

离散型手势的特点就是：一旦识别就无法取消，而且只会调用一次手势操作事件（初始化手势时指定的回调方法）。

​换句话说其他五种手势是连续型手势，而连续型手势的特点就是：会多次调用手势操作事件，而且在连续手势识别后可以取消手势。从下图可以看出两者调用操作事件的次数是不同的：

手势状态枚举如下：

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
};

对于离散型手势 uitapgesturerecgnizer 要么被识别，要么失败，点按（假设点按次数设置为1，并且没有添加长按手势）下去一次不松开则此时什么也不会发生，松开手指立即识别并调用操作事件，并且状态为3（已完成）。
但是连续型手势要复杂一些，就拿旋转手势来说，如果两个手指点下去不做任何操作，此时并不能识别手势（因为我们还没旋转）但是其实已经触发了触摸开始事件，此时处于状态0；如果此时旋转会被识别，也就会调用对应的操作事件，同时状态变成1（手势开始），但是状态1只有一瞬间；紧接着状态变为2（因为我们的旋转需要持续一会），并且重复调用操作事件（如果在事件中打印状态会重复打印2）；松开手指，此时状态变为3，并调用1次操作事件。

3、使用手势的步骤
使用手势很简单，分为三步：

创建手势识别器对象实例。创建时，指定一个回调方法，当手势开始，改变、或结束时，执行回调方法。

设置手势识别器对象实例的相关属性（可选部分）

添加到需要识别的 view 中。每个手势只对应一个 view，当屏幕触摸在 view 的边界内时，如果手势和预定的一样，那就会执行回调方法。

ps：一个手势只能对应一个 view，但是一个 view 可以有多个手势。建议在真机上测试这些手势，模拟器操作不太方便，可能导致认为手势失效的情况。（模拟器测试捏合和旋转手势时，按住 option 键，再用触摸板或鼠标操作）

4、举例说明
功能描述：

附加到两个图片视图 uiimageview 的有『拖动』、『捏合』、『旋转』、『点按』；

而『轻扫』和『自定义手势 kmgesturerecognizer』附加在根视图 uiview 中。

拖动：进行当前图片视图位置移动

捏合：进行当前图片视图缩放

旋转：进行当前图片视图角度旋转

点按：双击恢复当前图片视图的缩放、角度旋转、不透明度

长按：设置当前图片视图的不透明度为0.7

轻扫：左右轻扫设置两个图片视图为居中，同时以垂直居中的特定偏移量定位

自定义手势：挠痒功能，左右扫动共3次或以上，设置两个图片视图为居中，同时以水平居中的特定偏移量定位

效果如下：

kmgesturerecognizer.h

 #import <uikit/uikit.h>
 
 typedef ns_enum(nsuinteger, direction) {
  directionunknown,
  directionleft,
  directionright
 };
 
 @interface kmgesturerecognizer : uigesturerecognizer
 @property (assign, nonatomic) nsuinteger ticklecount; //挠痒次数
 @property (assign, nonatomic) cgpoint currentticklestart; //当前挠痒开始坐标位置
 @property (assign, nonatomic) direction lastdirection; //最后一次挠痒方向
 
 @end
kmgesturerecognizer.m

 #import "kmgesturerecognizer.h"
 #import <uikit/uigesturerecognizersubclass.h>
 
 @implementation kmgesturerecognizer
 #define kminticklespacing 20.0
 #define kmaxticklecount 3
 
 - (void)reset {
  _ticklecount = 0;
  _currentticklestart = cgpointzero;
  _lastdirection = directionunknown;
  
  if (self.state == uigesturerecognizerstatepossible) {
   self.state = uigesturerecognizerstatefailed;
  }
 }
 
 - (void)touchesbegan:(nsset *)touches withevent:(uievent *)event {
  uitouch *touch = [touches anyobject];
  _currentticklestart = [touch locationinview:self.view]; //设置当前挠痒开始坐标位置
 }
 
 - (void)touchesmoved:(nsset *)touches withevent:(uievent *)event {
  //『当前挠痒开始坐标位置』和『移动后坐标位置』进行 x 轴值比较，得到是向左还是向右移动
  uitouch *touch = [touches anyobject];
  cgpoint tickleend = [touch locationinview:self.view];
  cgfloat ticklespacing = tickleend.x - _currentticklestart.x;
  direction currentdirection = ticklespacing < 0 ? directionleft : directionright;
  
  //移动的 x 轴间距值是否符合要求，足够大
  if (abs(ticklespacing) >= kminticklespacing) {
   //判断是否有三次不同方向的动作，如果有则手势结束，将执行回调方法
   if (_lastdirection == directionunknown ||
    (_lastdirection == directionleft && currentdirection == directionright) ||
    (_lastdirection == directionright && currentdirection == directionleft)) {
    _ticklecount++;
    _currentticklestart = tickleend;
    _lastdirection = currentdirection;
    
    if (_ticklecount >= kmaxticklecount && self.state == uigesturerecognizerstatepossible) {
     self.state = uigesturerecognizerstateended;
     //nslog(@"自定义手势成功，将执行回调方法");
    }
   }
  }
 }
 
 - (void)touchesended:(nsset *)touches withevent:(uievent *)event {
  [self reset];
 }
 
 - (void)touchescancelled:(nsset *)touches withevent:(uievent *)event {
  [self reset];
 }
 
 @end

viewcontroller.h
#import <uikit/uikit.h>
#import "kmgesturerecognizer.h"

@interface viewcontroller : uiviewcontroller
@property (strong, nonatomic) uiimageview *imgv;
@property (strong, nonatomic) uiimageview *imgv2;
@property (strong, nonatomic) kmgesturerecognizer *customgesturerecognizer;

@end
viewcontroller.m

 #import "viewcontroller.h"
 
 @interface viewcontroller ()
 - (void)handlepan:(uipangesturerecognizer *)recognizer;
 - (void)handlepinch:(uipinchgesturerecognizer *)recognizer;
 - (void)handlerotation:(uirotationgesturerecognizer *)recognizer;
 - (void)handletap:(uitapgesturerecognizer *)recognizer;
 - (void)handlelongpress:(uilongpressgesturerecognizer *)recognizer;
 - (void)handleswipe:(uiswipegesturerecognizer *)recognizer;
 - (void)handlecustomgesturerecognizer:(kmgesturerecognizer *)recognizer;
 
 - (void)bindpan:(uiimageview *)imgvcustom;
 - (void)bindpinch:(uiimageview *)imgvcustom;
 - (void)bindrotation:(uiimageview *)imgvcustom;
 - (void)bindtap:(uiimageview *)imgvcustom;
 - (void)bindlongpress:(uiimageview *)imgvcustom;
 - (void)bindswipe;
 - (void)bingcustomgesturerecognizer;
 - (void)layoutui;
 @end
 
 @implementation viewcontroller
 
 - (void)viewdidload {
  [super viewdidload];
  
  [self layoutui];
 }
 
 - (void)didreceivememorywarning {
  [super didreceivememorywarning];
  // dispose of any resources that can be recreated.
 }
 
 #pragma mark - 处理手势操作
 /**
 * 处理拖动手势
 *
 * @param recognizer 拖动手势识别器对象实例
 */
 - (void)handlepan:(uipangesturerecognizer *)recognizer {
  //视图前置操作
  [recognizer.view.superview bringsubviewtofront:recognizer.view];
  
  cgpoint center = recognizer.view.center;
  cgfloat cornerradius = recognizer.view.frame.size.width / 2;
  cgpoint translation = [recognizer translationinview:self.view];
  //nslog(@"%@", nsstringfromcgpoint(translation));
  recognizer.view.center = cgpointmake(center.x + translation.x, center.y + translation.y);
  [recognizer settranslation:cgpointzero inview:self.view];
  
  if (recognizer.state == uigesturerecognizerstateended) {
  //计算速度向量的长度，当他小于200时，滑行会很短
  cgpoint velocity = [recognizer velocityinview:self.view];
  cgfloat magnitude = sqrtf((velocity.x * velocity.x) + (velocity.y * velocity.y));
  cgfloat slidemult = magnitude / 200;
  //nslog(@"magnitude: %f, slidemult: %f", magnitude, slidemult); //e.g. 397.973175, slidemult: 1.989866
  
  //基于速度和速度因素计算一个终点
  float slidefactor = 0.1 * slidemult;
  cgpoint finalpoint = cgpointmake(center.x + (velocity.x * slidefactor),
          center.y + (velocity.y * slidefactor));
  //限制最小［cornerradius］和最大边界值［self.view.bounds.size.width - cornerradius］，以免拖动出屏幕界限
  finalpoint.x = min(max(finalpoint.x, cornerradius),
       self.view.bounds.size.width - cornerradius);
  finalpoint.y = min(max(finalpoint.y, cornerradius),
       self.view.bounds.size.height - cornerradius);
  
  //使用 uiview 动画使 view 滑行到终点
  [uiview animatewithduration:slidefactor*2
       delay:0
       options:uiviewanimationoptioncurveeaseout
      animations:^{
       recognizer.view.center = finalpoint;
      }
      completion:nil];
 }
}

/**
* 处理捏合手势
*
* @param recognizer 捏合手势识别器对象实例
*/
- (void)handlepinch:(uipinchgesturerecognizer *)recognizer {
 cgfloat scale = recognizer.scale;
 recognizer.view.transform = cgaffinetransformscale(recognizer.view.transform, scale, scale); //在已缩放大小基础下进行累加变化；区别于：使用 cgaffinetransformmakescale 方法就是在原大小基础下进行变化
 recognizer.scale = 1.0;
}

/**
* 处理旋转手势
*
* @param recognizer 旋转手势识别器对象实例
*/
- (void)handlerotation:(uirotationgesturerecognizer *)recognizer {
 recognizer.view.transform = cgaffinetransformrotate(recognizer.view.transform, recognizer.rotation);
 recognizer.rotation = 0.0;
 }
 
 /**
 * 处理点按手势
 *
 * @param recognizer 点按手势识别器对象实例
 */
 - (void)handletap:(uitapgesturerecognizer *)recognizer {
  uiview *view = recognizer.view;
  view.transform = cgaffinetransformmakescale(1.0, 1.0);
  view.transform = cgaffinetransformmakerotation(0.0);
  view.alpha = 1.0;
 }
 
 /**
 * 处理长按手势
 *
 * @param recognizer 点按手势识别器对象实例
 */
 - (void)handlelongpress:(uilongpressgesturerecognizer *)recognizer {
  //长按的时候，设置不透明度为0.7
  recognizer.view.alpha = 0.7;
 }
 
 /**
 * 处理轻扫手势
 *
 * @param recognizer 轻扫手势识别器对象实例
 */
 - (void)handleswipe:(uiswipegesturerecognizer *)recognizer {
  //代码块方式封装操作方法
  void (^positionoperation)() = ^() {
   cgpoint newpoint = recognizer.view.center;
   newpoint.y -= 20.0;
   _imgv.center = newpoint;
   
   newpoint.y += 40.0;
   _imgv2.center = newpoint;
  };
  
  //根据轻扫方向，进行不同控制
  switch (recognizer.direction) {
   case uiswipegesturerecognizerdirectionright: {
    positionoperation();
    break;
   }
   case uiswipegesturerecognizerdirectionleft: {
    positionoperation();
    break;
   }
   case uiswipegesturerecognizerdirectionup: {
    break;
   }
   case uiswipegesturerecognizerdirectiondown: {
    break;
   }
  }
 }
 
 /**
 * 处理自定义手势
 *
 * @param recognizer 自定义手势识别器对象实例
 */
 - (void)handlecustomgesturerecognizer:(kmgesturerecognizer *)recognizer {
  //代码块方式封装操作方法
  void (^positionoperation)() = ^() {
   cgpoint newpoint = recognizer.view.center;
   newpoint.x -= 20.0;
   _imgv.center = newpoint;
   
   newpoint.x += 40.0;
   _imgv2.center = newpoint;
  };
  
  positionoperation();
 }
 
 
 #pragma mark - 绑定手势操作
 /**
 * 绑定拖动手势
 *
 * @param imgvcustom 绑定到图片视图对象实例
 */
 - (void)bindpan:(uiimageview *)imgvcustom {
  uipangesturerecognizer *recognizer = [[uipangesturerecognizer alloc] initwithtarget:self
                     action:@selector(handlepan:)];
  [imgvcustom addgesturerecognizer:recognizer];
 }
 
 /**
 * 绑定捏合手势
 *
 * @param imgvcustom 绑定到图片视图对象实例
 */
 - (void)bindpinch:(uiimageview *)imgvcustom {
  uipinchgesturerecognizer *recognizer = [[uipinchgesturerecognizer alloc] initwithtarget:self
                      action:@selector(handlepinch:)];
  [imgvcustom addgesturerecognizer:recognizer];
  //[recognizer requiregesturerecognizertofail:imgvcustom.gesturerecognizers.firstobject];
 }
 
 /**
 * 绑定旋转手势
 *
 * @param imgvcustom 绑定到图片视图对象实例
 */
 - (void)bindrotation:(uiimageview *)imgvcustom {
  uirotationgesturerecognizer *recognizer = [[uirotationgesturerecognizer alloc] initwithtarget:self
                       action:@selector(handlerotation:)];
  [imgvcustom addgesturerecognizer:recognizer];
 }
 
 /**
 * 绑定点按手势
 *
 * @param imgvcustom 绑定到图片视图对象实例
 */
 - (void)bindtap:(uiimageview *)imgvcustom {
  uitapgesturerecognizer *recognizer = [[uitapgesturerecognizer alloc] initwithtarget:self
                     action:@selector(handletap:)];
  //使用一根手指双击时，才触发点按手势识别器
  recognizer.numberoftapsrequired = 2;
  recognizer.numberoftouchesrequired = 1;
  [imgvcustom addgesturerecognizer:recognizer];
 }
 
 /**
 * 绑定长按手势
 *
 * @param imgvcustom 绑定到图片视图对象实例
 */
 - (void)bindlongpress:(uiimageview *)imgvcustom {
  uilongpressgesturerecognizer *recognizer = [[uilongpressgesturerecognizer alloc] initwithtarget:self action:@selector(handlelongpress:)];
  recognizer.minimumpressduration = 0.5; //设置最小长按时间；默认为0.5秒
  [imgvcustom addgesturerecognizer:recognizer];
 }
 
 /**
 * 绑定轻扫手势；支持四个方向的轻扫，但是不同的方向要分别定义轻扫手势
 */
 - (void)bindswipe {
  //向右轻扫手势
  uiswipegesturerecognizer *recognizer = [[uiswipegesturerecognizer alloc] initwithtarget:self
                      action:@selector(handleswipe:)];
  recognizer.direction = uiswipegesturerecognizerdirectionright; //设置轻扫方向；默认是 uiswipegesturerecognizerdirectionright，即向右轻扫
  [self.view addgesturerecognizer:recognizer];
  [recognizer requiregesturerecognizertofail:_customgesturerecognizer]; //设置以自定义挠痒手势优先识别
  
  //向左轻扫手势
  recognizer = [[uiswipegesturerecognizer alloc] initwithtarget:self
               action:@selector(handleswipe:)];
  recognizer.direction = uiswipegesturerecognizerdirectionleft;
  [self.view addgesturerecognizer:recognizer];
  [recognizer requiregesturerecognizertofail:_customgesturerecognizer]; //设置以自定义挠痒手势优先识别
 }
 
 /**
 * 绑定自定义挠痒手势；判断是否有三次不同方向的动作，如果有则手势结束，将执行回调方法
 */
 - (void)bingcustomgesturerecognizer {
  //当 recognizer.state 为 uigesturerecognizerstateended 时，才执行回调方法 handlecustomgesturerecognizer:
  
  //_customgesturerecognizer = [kmgesturerecognizer new];
  _customgesturerecognizer = [[kmgesturerecognizer alloc] initwithtarget:self
                  action:@selector(handlecustomgesturerecognizer:)];
  [self.view addgesturerecognizer:_customgesturerecognizer];
 }
 
 - (void)layoutui {
  //图片视图 _imgv
  uiimage *img = [uiimage imagenamed:@"emoticon_tusiji_icon"];
  cgfloat cornerradius = img.size.width;
  _imgv = [[uiimageview alloc] initwithimage:img];
  _imgv.frame = cgrectmake(20.0, 20.0,
        cornerradius * 2, cornerradius * 2);
  _imgv.userinteractionenabled = yes;
  _imgv.layer.maskstobounds = yes;
  _imgv.layer.cornerradius = cornerradius;
  _imgv.layer.borderwidth = 2.0;
  _imgv.layer.bordercolor = [uicolor graycolor].cgcolor;
  [self.view addsubview:_imgv];
  
  //图片视图 _imgv2
  img = [uiimage imagenamed:@"emoticon_tusiji_icon2"];
  cornerradius = img.size.width;
  _imgv2 = [[uiimageview alloc] initwithimage:img];
  _imgv2.frame = cgrectmake(20.0, 40.0 + _imgv.frame.size.height,
        cornerradius * 2, cornerradius * 2);
  _imgv2.userinteractionenabled = yes;
  _imgv2.layer.maskstobounds = yes;
  _imgv2.layer.cornerradius = cornerradius;
  _imgv2.layer.borderwidth = 2.0;
  _imgv2.layer.bordercolor = [uicolor orangecolor].cgcolor;
  [self.view addsubview:_imgv2];
  
  
  [self bindpan:_imgv];
  [self bindpinch:_imgv];
  [self bindrotation:_imgv];
  [self bindtap:_imgv];
  [self bindlongpress:_imgv];
  
  [self bindpan:_imgv2];
  [self bindpinch:_imgv2];
  [self bindrotation:_imgv2];
  [self bindtap:_imgv2];
  [self bindlongpress:_imgv2];
  
  //为了处理手势识别优先级的问题，这里需先绑定自定义挠痒手势
  [self bingcustomgesturerecognizer];
  [self bindswipe];
 }
 
 @end

以上代码就是关于ios手势操作（拖动、捏合、旋转、点按、长按、轻扫、自定义）的详解，希望对大家有所帮助。