iOS 手勢(shì)

    1.如果一個(gè)控件繼承于 UIControl巍实，那么它將不需要手勢(shì)
    2.所有控件都可以添加手勢(shì)
    [控件 addGestureRecognizer: ]
    3.iOS 系統(tǒng)提供的手勢(shì)有哪些
 
    UITapGestureRecognizer 點(diǎn)擊
    UISwipeGestureRecognizer 輕掃
    UIPanGestureRecognizer 拖動(dòng)
    UIRotationGestureRecognizer 旋轉(zhuǎn)
    UIPinchGestureRecognizer 捏合
    UILongPressGestureRecognizer 長(zhǎng)按
 
    4.iOS 自定義的手勢(shì)都是具有相同的父類  UIGestureRecognizer
    5.UIGestureRecognizer 這個(gè)手勢(shì)父類是如何封裝滓技？
    
    UIGestureRecognizer  這個(gè)父類可以看做一個(gè)抽象類，并不具備手勢(shì)的具體功能棚潦，但是它提供了子類共有的初始化方法令漂、屬性孽亲、代理
    <共有的初始化方法>
    - (instancetype)initWithTarget:(nullable id)target action:(nullable SEL)action 
 
    <2>手勢(shì)的狀態(tài)  state
    <3>手勢(shì)是否有效 enable
    <4>代理 delegate
    <5>被添加手勢(shì)的 view

手勢(shì).gif

/** 圖片 */
@property (nonatomic,strong) UIImageView *imageView;
/** 數(shù)組 */
@property (nonatomic,strong) NSArray *images;
/** 圖片張數(shù) */
@property int count;

     _count = 0;
     _images = @[[UIImage imageNamed:@"00"],[UIImage imageNamed:@"01"],[UIImage imageNamed:@"02"]];
     _imageView = [[UIImageView alloc] initWithFrame:CGRectMake([UIScreen mainScreen].bounds.size.width / 2 - 50, [UIScreen mainScreen].bounds.size.height / 2 -100, 100, 200)];
     _imageView.image = _images[_count];
     _imageView.contentMode = UIViewContentModeScaleAspectFit;
     [self.view addSubview:_imageView];

• 手勢(shì)需要開(kāi)啟用戶交互

    //手勢(shì)需要開(kāi)啟用戶交互
    _imageView.userInteractionEnabled = YES;

點(diǎn)擊手勢(shì)

• 單擊手勢(shì)

    //單擊手勢(shì)
    UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(singleTapAction:)];
    [_imageView addGestureRecognizer:singleTap];

• 雙擊手勢(shì) 添加 numberOfTapsRequired屬性 能判斷點(diǎn)擊次數(shù)

    UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doubleTapAction:)];
    //判斷點(diǎn)擊次數(shù)
    doubleTap.numberOfTapsRequired = 2;
    [singleTap requireGestureRecognizerToFail:doubleTap];
    [_imageView addGestureRecognizer:doubleTap];

• 三擊手勢(shì)

    UITapGestureRecognizer *threeTop = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(TapGestureAction:)];
    threeTop.numberOfTapsRequired = 3;
    [doubleTap requireGestureRecognizerToFail:threeTop];
    [_imageView addGestureRecognizer:threeTop];

• 點(diǎn)擊事件方法

    -(void)TapGestureAction:(UITapGestureRecognizer *)sender
    {
        if (sender.numberOfTapsRequired == 1) {
            NSLog(@"單擊");
    }
        else if (sender.numberOfTapsRequired == 2) {
            NSLog(@"雙擊");
    }
        else
    {
            NSLog(@"三擊");
    }
    }

輕掃手勢(shì)

• 向左輕掃

    UISwipeGestureRecognizer *leftSwipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeAction:)];
    leftSwipe.direction = UISwipeGestureRecognizerDirectionLeft; //左
    [_imageView addGestureRecognizer:leftSwipe];

• 向右輕掃

    UISwipeGestureRecognizer *rightSwipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeAction:)];
    rightSwipe.direction = UISwipeGestureRecognizerDirectionRight;
    [_imageView addGestureRecognizer:rightSwipe];

• 輕掃手勢(shì)（左右）的事件方法

-(void)swipeAction:(UISwipeGestureRecognizer *)sender
{
    switch (sender.direction) {
        case UISwipeGestureRecognizerDirectionLeft:
        {
            NSLog(@"向左輕掃");
            if (_count > _images.count - 2) {
                
                //掃到最右一張彈出警示框
                UIAlertController *alertController = [UIAlertController alertControllerWithTitle:nil message:@"最后一張" preferredStyle:UIAlertControllerStyleAlert];
                
                UIAlertAction *sure = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil];
                
                [alertController addAction:sure];
                [self presentViewController:alertController animated:YES completion:nil];
                
                break;
            }
            [UIView beginAnimations:nil context:nil];
            [UIView setAnimationDuration:1.0f];
            [UIView setAnimationTransition:UIViewAnimationTransitionCurlDown forView:_imageView cache:YES];
            [UIView commitAnimations];
            
            
               _imageView.image = _images[++_count];
        }
            break;
            case UISwipeGestureRecognizerDirectionRight:
        {
            NSLog(@"向右輕掃");
            if (_count < _images.count - 2) {
                UIAlertController *alertController = [UIAlertController alertControllerWithTitle:nil message:@"第一張" preferredStyle:UIAlertControllerStyleAlert];
                
                UIAlertAction *sure = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil];
                
                [alertController addAction:sure];
                [self presentViewController:alertController animated:YES completion:nil];
                
                break;
            }
            [UIView beginAnimations:nil context:nil];
            [UIView setAnimationDuration:1.0f];
            [UIView setAnimationTransition:UIViewAnimationTransitionCurlDown forView:_imageView cache:YES];
            [UIView commitAnimations];
            
            _imageView.image = _images[--_count];
        }
        default:
            break;
    }
}

拖動(dòng)手勢(shì)

• 拖動(dòng)

    UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGestureAction:)];
    [_imageView addGestureRecognizer:panGesture];

• 拖動(dòng)事件方法

-(void)panGestureAction:(UIPanGestureRecognizer *)sender
{
    NSLog(@"拖動(dòng)");
    //轉(zhuǎn)換坐標(biāo)系
   CGPoint point = [sender translationInView:self.view];
    _imageView.center = CGPointMake(_imageView.center.x + point.x, _imageView.center.y + point.y);
    [sender setTranslation:CGPointZero inView:self.view];
}

旋轉(zhuǎn)手勢(shì)

• 旋轉(zhuǎn)

    UIRotationGestureRecognizer *rotationGestur = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotationAction:)];
    [_imageView addGestureRecognizer:rotationGestur];

• 旋轉(zhuǎn)事件方法

    -(void)rotationAction:(UIRotationGestureRecognizer *)sender
    {
        NSLog(@"旋轉(zhuǎn)");
        _imageView.transform = CGAffineTransformMakeRotation(sender.rotation);
    }

捏合手勢(shì)

• 捏合

    UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinchGestureAction:)];
    [_imageView addGestureRecognizer:pinchGesture];

• 捏合事件方法

-(void)pinchGestureAction:(UIPinchGestureRecognizer *)sender
{
    NSLog(@"捏合");
    _imageView.transform = CGAffineTransformMakeScale(sender.scale,sender.scale);
}

長(zhǎng)按事件

• 長(zhǎng)按

    UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressAction:)];
    [_imageView addGestureRecognizer:longPress];

• 長(zhǎng)按事件方法

-(void)longPressAction:(UILongPressGestureRecognizer *)sender
{
    NSLog(@"長(zhǎng)按");
    
    if (sender.state == UIGestureRecognizerStateBegan) {
        
        UIAlertController *alertController = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleActionSheet];
        
        UIAlertAction *cancle = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
            
        }];
        [alertController addAction:cancle];
        
        
        UIAlertAction *savePhoto = [UIAlertAction actionWithTitle:@"保存到相冊(cè)" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            
            UIImageWriteToSavedPhotosAlbum(_imageView.image, self, @selector(image:didFinishSavingWithError:contextInfo:), NULL);
            
        }];
        [alertController addAction:savePhoto];
        
        
        UIAlertAction *openPhoto = [UIAlertAction actionWithTitle:@"打開(kāi)相冊(cè)" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            
            UIImagePickerController *picker = [[UIImagePickerController alloc] init];
            //資源類型為打開(kāi)相冊(cè)
            picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
            picker.delegate = self;
            //選擇后的圖片可以被編輯
            picker.allowsEditing = YES;
            
            [self presentViewController:picker animated:YES completion:nil];
            
        }];
        [alertController addAction:openPhoto];
        
        
        UIAlertAction *turnonCamer = [UIAlertAction actionWithTitle:@"打開(kāi)相機(jī)" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            
            UIImagePickerController *picker = [[UIImagePickerController alloc] init];
            picker.sourceType = UIImagePickerControllerSourceTypeCamera;
            picker.delegate = self;
            picker.allowsEditing = YES;
            
            [self presentViewController:picker animated:YES completion:nil];
        }];
        [alertController addAction:turnonCamer];
        
        [self presentViewController:alertController animated:YES completion:^{
            
        }];
    }
}

• 保存照片的事件方法

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
    NSString *msg = nil;
    if (!error) {
        msg = @"保存成功";
    }
    else
    {
        msg = @"圖片保存失敗";
    }
    
    NSLog(@"%@",msg);
    
}

• 打開(kāi)相冊(cè)和打開(kāi)相機(jī)的事件方法

    -(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info
    {
    //打開(kāi)相機(jī)
    if (picker.sourceType == UIImagePickerControllerSourceTypeCamera) {
        
        _imageView.image = info[@"UIImagePickerControllerEditedImage"];
    }
    //打開(kāi)相冊(cè)
    else
    {
        NSLog(@"info = %@",info);
        //獲取永華編輯之后的圖片
        _imageView.image = info[@"UIImagePickerControllerEditedImage"];
       
    }
    [self dismissViewControllerAnimated:YES completion:nil];
    }