手势---iOS笔记摘录

目录
    1. 系统自带手势
    2. 自定义手势
    3. 手势基类

注意：
    UIImageView 和 UILabel 是少数几个不可交互的控件
    需要设置userInteractionEnabled为true，否则不允许交互。

1. 系统自带手势

1. 单击手势 UITapGestureRecognizer

    UITapGestureRecognizer *tapG=[[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(handleTap:)];
    tapG.numberOfTapsRequired=1;    // 点击次数（默认：1）
    tapG.numberOfTouchesRequired=1; // 点击手指数（默认：1）
    [imgV1 addGestureRecognizer:tapG];  // imgV 必须设置为可交互

-(void)handleTap:(UITapGestureRecognizer *)tapG{
    //
    UIImageView *imgV=(UIImageView *)tapG.view;
}

2. 缩放手势 UIPinchGestureRecognizer

    // 缩放手势
    UIPinchGestureRecognizer *pinchG=[[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(handlePinch:)];
    [pinchG setScale:0.5];  // 缩放比例
    // pinchG.velocity(readOnly)
    [[UIImageView new]addGestureRecognizer:pinchG];

-(void)handlePinch:(UIPinchGestureRecognizer *)pinchG{
    //
    UIImageView *imgV=(UIImageView *)pinchG.view;
    // pinchG.scale  
}

3.旋转手势 UIRotationGestureRecognizer

    // 旋转手势
    UIRotationGestureRecognizer *roteG=[[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(handleRote:)];
    [roteG setRotation:M_PI_2]; // 旋转角度
    // roteG.velocity
    [[UIImageView new]addGestureRecognizer:roteG];

-(void)handleRote:(UIRotationGestureRecognizer *)roteG{
    //
    UIImageView *imgV=(UIImageView *)roteG.view;
    // roteG.rotation
}

4.扫动手势 UISwipeGestureRecognizer

    // 扫动手势
    UISwipeGestureRecognizer *swipeG=[[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleSwipe:)];
    swipeG.numberOfTouchesRequired=1;   // 默认：1
    swipeG.direction=UISwipeGestureRecognizerDirectionLeft; // 如果多个方向，则添加多个手势
    [[UIImageView new]addGestureRecognizer:swipeG];

-(void)handleSwipe:(UISwipeGestureRecognizer *)swipeG{
    //
    UIImageView *imgV=(UIImageView *)swipeG.view;
}

5. 拖动手势 UIPanGestureRecognizer

    // 拖动手势
    UIPanGestureRecognizer *panG=[[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(handlePan:)];
    [panG setMaximumNumberOfTouches:2]; // 最小手指数
    [panG setMinimumNumberOfTouches:1]; // 最大手指数
    [[UIImageView new]addGestureRecognizer:panG];

-(void)handlePan:(UIPanGestureRecognizer *)panG{
    //
    UIButton *itemButton=(UIButton *)panG.view;
    CGPoint transP=[panG translationInView:self];
    NSLog(@"%f  %f",transP.x,transP.y);
    
    //
    if(transP.x>0&&transP.x<294-95){
        [UIView animateWithDuration:0.1 animations:^{
            [itemButton setTransform:CGAffineTransformMakeTranslation(transP.x, 0)];
        }];
    }else if(transP.x>=294){
        [self.subject sendNext:@(100)];
    }
    
    //
    if(panG.state==UIGestureRecognizerStateEnded){
        [UIView animateWithDuration:0.1 animations:^{
            [itemButton setTransform:CGAffineTransformIdentity];
        }];
    }
  
    // [panG setTranslation:CGPointZero inView:self.view]; // reset
}

6. 长按手势 UILongPressGestureRecognizer

    // 长按手势
    UILongPressGestureRecognizer *longPressG=[[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(handleLongPress:)];
    longPressG.numberOfTouchesRequired=1;   // 手指数（默认：1）
    longPressG.numberOfTapsRequired=1;      // 点击数（默认：0）
    longPressG.minimumPressDuration=1;      // 最小的长按时间(默认：0.5)
    longPressG.allowableMovement=10;        // 最大的移动距离（默认：10ps）
    [[UIImageView new]addGestureRecognizer:longPressG];

-(void)handleLongPress:(UIPanGestureRecognizer *)longPressG{
    //
    UIImageView *imgV=(UIImageView *)longPressG.view;
    
}

2. 自定义手势

#import <UIKit/UIKit.h>
@interface CustomGestureRecognizer : UIGestureRecognizer
@end

#import "CustomGestureRecognizer.h"
#import <UIkit/UIGestureRecognizerSubclass.h>
@implementation CustomGestureRecognizer

-(instancetype)initWithTarget:(id)target action:(SEL)action{
    return [super initWithTarget:target action:action];
}

// 开始触摸时调用
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
// 触摸移动时调用
-(void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
// 触摸结束时调用
-(void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
// 触摸取消时调用
-(void)touchesCancelled:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
@end

3. 手势基类

UIGestureRecognizer : NSObject   
    所有手势的基类，通常不直接使用

    // 
    UIGestureRecognizer *g=[[UIGestureRecognizer alloc]initWithTarget:self action:@selector(handleG)];
    // 添加targetAction
    [g addTarget:OtherVC action:@selector(handleG)];
    // 移除targetAction
    [g removeTarget:OtherVC action:@selector(handleG)];

    // 手势的当前状态(readOnly)
    UIGestureRecognizerState state=g.state;
    // 获取 手势操作的View（readonly）
    UIView *view=g.view;
    // 获取 手指数（readonly）
    NSUInteger numberOfTouches=g.numberOfTouches;

    // 设置 是否可用（默认：true）
    [g setEnabled:true];
    // 获取 是否可用
    BOOL isEnabled=g.isEnabled;
    // 设置 手势名
    [g setName:@""];
    // 获取 手势名
    NSString *name=g.name;


    // 获取 指定触摸点的坐标
    CGPoint touchPoint=[g locationOfTouch:0 inView:g.view];
    // 获取 触摸点的坐标
    CGPoint touchPoint2=[g locationInView:g.view];

    // 当两个手势有【冲突】时,手势1只会在手势2失败时才会有效
    [g1 requireGestureRecognizerToFail:g2];

    // 设置 是否同时考虑不同手势（true会忽略不同手势）
    [g setRequiresExclusiveTouchType:true]；


    /*
     手势识别和触摸事件是两个独立的事，只是可以通过以下3个属性互相影响
     在默认情况下（即这3个属性都处于默认值的情况下），如果触摸window，首先由window上最先符合条件的控件(该控件记为hit-test view)接收到该touch并触发触摸事件touchesBegan。同时如果某个控件的手势识别器接收到了该touch，就会进行识别。手势识别成功之后发送触摸事件touchesCancelled给hit-testview，hit-test view不再响应touch。
     */
    // 默认为YES,这种情况下当手势识别器识别到touch之后，会发送touchesCancelled给hit-testview以取消hit-test view对touch的响应，这个时候只有手势识别器响应touch。当设置成NO时，手势识别器识别到touch之后不会发送touchesCancelled给hit-test，这个时候手势识别器和hit-test view均响应touch。
    [g setCancelsTouchesInView:true];
    // 默认是NO，这种情况下当发生一个touch时，手势识别器先捕捉到到touch，然后发给hit-testview，两者各自做出响应。如果设置为YES，手势识别器在识别的过程中（注意是识别过程），不会将touch发给hit-test view，即hit-testview不会有任何触摸事件。只有在识别失败之后才会将touch发给hit-testview，这种情况下hit-test view的响应会延迟约0.15ms。
    [g setDelaysTouchesBegan:true];
    // 默认为YES。这种情况下发生一个touch时，在手势识别成功后,发送给touchesCancelled消息给hit-testview，手势识别失败时，会延迟大概0.15ms,期间没有接收到别的touch才会发送touchesEnded。如果设置为NO，则不会延迟，即会立即发送touchesEnded以结束当前触摸。
    [g setDelaysTouchesEnded:true];
    
    
    // 设置 允许触摸的类型
    [g setAllowedTouchTypes:@[[NSNumber numberWithInt:0]]];
    // 设置 允许按压的类型
    [g setAllowedPressTypes:@[[NSNumber numberWithInt:0]]];

dele

    // dele<UIGestureRecognizerDelegate>
    [g setDelegate:self];

#pragma mark dele -UIGestureRecognizerDelegate
/*
 是否允许手势
 */
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer{
    return true;
}
// 解决有水平方向滚动的ScrollView时边缘返回手势失效的问题
// 是否支持多手势（默认：false，识别到第一个手势则停止识别第二个手势）（true，则识别到第一个手势，还会去识别第二个手势）
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
    return YES;
}
// 当第一个手势和第二个手势发生冲突时，第二个失效
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
    return [gestureRecognizer isKindOfClass:UIScreenEdgePanGestureRecognizer.class];
}


// 当第一个手势和第二个手势发生冲突时，第一个失效
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRequireFailureOfGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
    return true;
}
// 是否允许 手势识别（默认：true）
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch{
    return false;   // 禁止识别
}
// 开始识别手势时调用（可用于：控件某范围有效）
-(BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer{
    return true;
}

UIViewController 或 UIView 中可覆写

// UIViewController：UIResponder
// 开始触摸
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
// 触摸后移动
-(void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
// 触摸结束
-(void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}
// 触摸取消
-(void)touchesCancelled:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
}

获取到侧滑手势（侧滑手势继承于：UIPanGestureRecognizer）

        // 获取到侧滑手势
        NSArray *gestureArray = self.navigationController.view.gestureRecognizers;
        for (UIGestureRecognizer *gesture in gestureArray) {
            if ([gesture isKindOfClass:[UIScreenEdgePanGestureRecognizer class]]) {
                
            }
        }