IOS基础-设计模式、手势识别器

target/action设计模式

每个视图点击事件都不一样，我们无法预先知道这个视图点击之后都要实现什么效果，因此我们在类内部提前写好点击事件不科学

使用target/action实现解耦

@implementation myView


- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    NSLog(@"整个人都不好了");
    //此时，不确定有那个对象实现action方法，
    //也不确定执行什么方法，这样可以达到解耦的目的，即：实现触摸动作和触摸之后做什么操作完全分开
    [self.target performSelector:self.action withObject:self afterDelay:0];
}
@end



- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    NSLog(@"整个人都不好了");
    //此时，不确定有那个对象实现action方法，
    //也不确定执行什么方法，这样可以达到解耦的目的，即：实现触摸动作和触摸之后做什么操作完全分开
    [self.target performSelector:self.action withObject:self afterDelay:0];
}
@end





@implementation RootViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor = [UIColor colorWithRed:0 green:49/255.0 blue:79/255.0 alpha:1];
    myView *view = [[myView alloc]initWithFrame:CGRectMake(100, 100, 100, 100)];
    view.backgroundColor = [UIColor colorWithRed:113/255.0 green:150/255.0 blue:159/255.0 alpha:1];
    view.layer.cornerRadius = 8;
    [self.view addSubview:view];
    view.tag = 100;
    //设置view的目标对象为控制器（self）
    view.target =self;
    //设置view要执行的方法（行为）；
    view.action = @selector(changeColor);

手势识别器

手势识别器是对触摸事件做了封装，我们无需自己去判断某个手势是否触发，手势识别器本身起到了识别作用，我们把重心放在识别之后要做什么操作上

手势识别器是iOS中比较抽象的一个类，用于识别一个手势，即 有规律的触摸

#import "PhotoViewController.h"
#define kImageCount 6
@interface PhotoViewController ()

{
    int _currentIndex;//当前图片索引
}





@end

@implementation PhotoViewController

- (void)dealloc{
    [_imageView release];
    [super dealloc];
}


- (void)viewDidLoad {
    [super viewDidLoad];
    
    [self initLayout];
    [self addGesture];
    
}


#pragma mark  布局
- (void)initLayout{
    /*添加图片展示控件*/
    CGSize screenSize = [UIScreen mainScreen].applicationFrame.size;
    CGFloat topPadding = 20;
    CGFloat y = 22 + 44 +topPadding;
    CGFloat height = screenSize.height - y - topPadding;
    
    CGRect imageFrame = CGRectMake(0, y, screenSize.width, height);
    _imageView = [[UIImageView alloc] initWithFrame:imageFrame];
    _imageView.contentMode = UIViewContentModeScaleAspectFit;//设置内容模式为缩放填充
    _imageView.userInteractionEnabled = YES;//这里必须设置为yes，否则无法接收手势操作
    [self.view addSubview:_imageView];
    
    //添加默认图片
    UIImage *image = [UIImage imageNamed:@"0.png"];
    _imageView.image = image;
    [self showPhotoName];
    
}




#pragma mark  添加手势
- (void)addGesture{
    /*1.添加点按手势*/
    //创建手势对象
    UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tapImage:)];
    //设置手势属性
    tapGesture.numberOfTapsRequired = 1;//设置点按次数，默认为1，注意在iOS中很少用到双击操作
    tapGesture.numberOfTouchesRequired = 1;//点按的手指数
    //添加手势到对象（注意，这里添加到控制器视图中，而不是图片上，否则点击空白无法隐藏导航栏）
    [self.view addGestureRecognizer:tapGesture];
    
    /*2.添加长按手势*/
    //创建手势对象
    UILongPressGestureRecognizer *longPressGesture = [[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(longPressGesture:)];
    longPressGesture.minimumPressDuration = 0.5;//设置时长，默认0.5
    //注意由于是长按图片操作，所以手势添加在图片，而不是视图控制器上
    [_imageView addGestureRecognizer:longPressGesture];
    
    /*3.添加捏合手势*/
    UIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinchGesture:)];
    [self.view addGestureRecognizer:pinchGesture];
    
    /*4.添加旋转手势*/
    UIRotationGestureRecognizer *rotationGesture = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotationGesture:)];
    [self.view addGestureRecognizer:rotationGesture];
    
    /*5.添加拖动手势*/
    UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGesture:)];
    [self.view addGestureRecognizer:panGesture];
    
//    6.添加清扫手势
    UISwipeGestureRecognizer *swipeGestureToRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeGesture:)];
    swipeGestureToRight.direction = UISwipeGestureRecognizerDirectionRight;//默认是向右轻扫
    [self.view addGestureRecognizer:swipeGestureToRight];
    
    UISwipeGestureRecognizer *swipeGestureToLeft = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeGesture:)];
    swipeGestureToLeft.direction = UISwipeGestureRecognizerDirectionLeft;
    [self.view addGestureRecognizer:swipeGestureToLeft];
    
//    解决在图片上滑动时拖动手势和轻扫手势的冲突
    [panGesture requireGestureRecognizerToFail:swipeGestureToRight];
    [panGesture requireGestureRecognizerToFail:swipeGestureToLeft];
    
    //解决拖动和长按手势之间的冲突
    [longPressGesture requireGestureRecognizerToFail:panGesture];
    
    
}



#pragma mark  显示图片名称
- (void)showPhotoName{
    NSString *title = [NSString stringWithFormat:@"%i.png",_currentIndex];
    [self setTitle:title];
}

#pragma mark  下一张图片
- (void)nextImage{
    int index = (_currentIndex + kImageCount + 1) % kImageCount;
    NSString *imageName = [NSString stringWithFormat:@"%i.png",index];
    _imageView.image = [UIImage imageNamed:imageName];
    _currentIndex = index;
    [self showPhotoName];
}






#pragma mark  上一张图片
- (void)lastImage{
    int index = (_currentIndex + kImageCount - 1) % kImageCount;
    NSString *imageName = [NSString stringWithFormat:@"%i.png",index];
    _imageView.image = [UIImage imageNamed:imageName];
    [self showPhotoName];
}




#pragma mark  - 手势操作
#pragma mark   点按隐藏或者显示导航栏
- (void)tapImage:(UITapGestureRecognizer *)gesture{
    NSLog(@"点按隐藏或显示导航");
    BOOL hidden = !self.navigationController.navigationBarHidden;
    [self.navigationController setNavigationBarHidden:hidden animated:YES];
}

#pragma mark  长按显示是否删除
- (void)longPressGesture:(UILongPressGestureRecognizer *)gesture{
    NSLog(@"长按删除");
    //注意在手势里面有一个view属性可以获取点按的视图
//    UIImageView *imageView = (UIImageView *)gesture.view;
    
    if (gesture.state == UIGestureRecognizerStateBegan) {
        UIActionSheet *actionSheet = [[UIActionSheet alloc] initWithTitle:@"系统提示" delegate:nil cancelButtonTitle:@"取消" destructiveButtonTitle:@"删除图片" otherButtonTitles: nil];
        [actionSheet showInView:self.view];
    }
}

#pragma mark 捏合时缩放图片
- (void)pinchGesture:(UIPinchGestureRecognizer *)gesture{
    NSLog(@"捏合缩放图片");
    if (gesture.state == UIGestureRecognizerStateChanged) {
        //捏合手势scale属性记录的缩放比例
        _imageView.transform = CGAffineTransformMakeScale(gesture.scale, gesture.scale);
    }
    else if(gesture.state == UIGestureRecognizerStateEnded){
        [UIView animateWithDuration:.5 animations:^{
            _imageView.transform = CGAffineTransformIdentity;//取消一切形变
        }];
    }
}

#pragma mark  旋转图片
- (void)rotationGesture:(UIRotationGestureRecognizer *)gesture{
    NSLog(@"旋转跳跃");
    if (gesture.state == UIGestureRecognizerStateChanged) {
        //旋转手势中rotation属性记录了旋转弧度
        _imageView.transform = CGAffineTransformMakeRotation(gesture.rotation) ;
    }else if(gesture.state == UIGestureRecognizerStateEnded){
        [UIView animateWithDuration:.8 animations:^{
            _imageView.transform = CGAffineTransformIdentity;//取消形变
        }];
    }
    
}

#pragma  mark  拖动图片
- (void)panGesture:(UIPanGestureRecognizer *)gesture{
    NSLog(@"拖动图片");
    if (gesture.state == UIGestureRecognizerStateChanged) {
        CGPoint transLocation = [gesture translationInView:self.view];
        _imageView.transform = CGAffineTransformMakeTranslation(transLocation.x, transLocation.y);
        NSLog(@"transLoaction.x =%f ",transLocation.x);
    }else if(gesture.state == UIGestureRecognizerStateEnded){
        CGPoint transLocation = [gesture translationInView:self.view];
        if (transLocation.x > 150) {
            [self nextImage];
            [UIView animateWithDuration:.5 animations:^{
                _imageView.transform = CGAffineTransformIdentity;
            }];
        }else
        [UIView animateWithDuration:.5 animations:^{
            _imageView.transform = CGAffineTransformIdentity;
        }];
        if (transLocation.x < -150) {
            [self lastImage];
            [UIView animateWithDuration:.5 animations:^{
                _imageView.transform = CGAffineTransformIdentity;
            }];
        }else
            [UIView animateWithDuration:.5 animations:^{
                _imageView.transform = CGAffineTransformIdentity;
            }];
    }
}

#pragma mark  轻扫查看上一张或下一张
- (void)swipeGesture:(UISwipeGestureRecognizer *)gesture{
    //注意，轻扫是连续手势，但是只有在识别结束后才触发，不用判断状态
    if (gesture.state == UIGestureRecognizerStateEnded) {
        if (gesture.direction == UISwipeGestureRecognizerDirectionRight) {
            [self nextImage];
            NSLog(@"right");
        }else if(gesture.direction == UISwipeGestureRecognizerDirectionLeft){
            [self lastImage];
            NSLog(@"left");
        }
    }
}