UIImageView 在动画到 alpha 0 时如何被触摸？

Question

有人帮忙！

这是我想要实现的：

• 当 UIImageView 变为 alpha 0（隐藏）时
• 可以触摸
• 使其 alpha 变为 1（未隐藏）。

但是 UIImageView 在动画时没有被触摸（=变成 alpha 0）。

我在stackoverflow上尝试了一百个技能，但没有奏效。

他们是.......

1. UIViewAnimationOptionAllowUserInteraction
2. setUserInteractionEnabled:YES;
3. 触摸开始
4. 手势识别器选项
5. 等等..

只有函数“hitTest”有效，但在动画期间无效。

请回复。谢谢你。 以下是我的代码。

#import "ViewController.h"
#define AD @"text.png"
#import <QuartzCore/QuartzCore.h>

@interface ViewController ()

@end

@implementation ViewController


@synthesize scrollData=_scrollData;
@synthesize adImage=_adImage;



   - (void)viewDidLoad
    {
        //_adImage is UIImageView
        _adImage=[[adImage alloc] initWithImage:[UIImage imageNamed:AD]];
_scrollData.scrollView.delegate = self;

    UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(singleTapGestureCaptured:)];

        [_adImage addGestureRecognizer:singleTap];
        [_adImage setMultipleTouchEnabled:YES];
        [_adImage setUserInteractionEnabled:YES];

        [self.view addSubview:_adImage];
        _adImage.alpha=0;
        [_adImage setUp_pt:CGPointMake(160,250)];
        _adImage.center=_adImage.up_pt;

        [super viewDidLoad];
        [self hideImage:_adImage delay:0];
        [self becomeFirstResponder];
    }


    - (void)hideImageComplete:(UIView*)v
    {
        [self hideImage:v delay:0];
    }

    - (void)hideImage:(UIImageView*)v delay:(int)nDelay
    {
        [_adImage becomeFirstResponder];

        [UIView animateWithDuration:1
                              delay:nDelay
                            options:
         (UIViewAnimationOptionCurveEaseIn | UIViewAnimationOptionAllowUserInteraction)
                         animations: ^
         {
                 _adImage.alpha=0.0f;
         }
                         completion:^(BOOL completed){
                             [self hideImageComplete:v];
                         }];
    }

- (void)singleTapGestureCaptured:(UITapGestureRecognizer *)gesture
{
    NSLog(@"Gesture event on view");
    _adImage.alpha=1;
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    return YES;
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch{
    return YES;
}




- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    NSLog(@"hit!!");
    [super touchesBegan:touches withEvent:event];
    UITouch *touch = [touches anyObject];
    CGPoint touchPoint = [touch locationInView:self.view];
    CGPoint touchLocation = [touch locationInView:self.view];
    _adImage.alpha=1;

}


@end



@implementation adImage
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [touches anyObject];
    CGPoint touchPoint = [touch locationInView:self];
    if ([[[self layer] presentationLayer] hitTest:touchPoint]) {
        [self.layer removeAllAnimations];
    }
}
-(UIView*)hitTest:(CGPoint)point withEvent:(UIEvent *)event{
    if ([[self.layer presentationLayer] hitTest:point]) {
        NSLog(@"hit!!");
        self.alpha=1;
        return self;
    }
    return [super hitTest:point withEvent:event];
}

@synthesize up_pt;


@end

这是我的 ViewController.h 代码。

#import <UIKit/UIKit.h>


@interface adImage : UIImageView {
}


//@property (strong, nonatomic) UIImageView *imageView;

@property (assign)CGPoint up_pt;


@end



@interface ViewController : UIViewController <UIScrollViewDelegate>{
}

- (void)hideImageComplete:(UIView*)v;
- (void)hideImage:(UIView*)v delay:(int)nDelay;

@property (strong, nonatomic) adImage *adImage;
@property(nonatomic, strong) IBOutlet UIWebView *scrollData;


@end

Answer 1

我有答案，但首先：

• 总是以大写字母命名一个类，即 AdImageView（它也是一个图像视图而不是纯视图子类）

• 我拿走了你的代码，但注释掉了你可能需要也可能不需要的所有触摸方法

• 这里的根本问题是，如果 alpha 为 0，UIGestureRecognizer 将不起作用，因此您会看到 alpha=0 的动画被分成两部分，几乎为 0，然后为 0。如果用户点击取消，然后最后的完成块将视图返回到 0

代码：

- (void)hideImage:(UIImageView*)v delay:(int)nDelay
{
    //[_adImage becomeFirstResponder];

    [UIView animateWithDuration:(3.0f - 0.1f)
                          delay:nDelay
                        options: (UIViewAnimationOptionCurveEaseIn | 
                                  UIViewAnimationOptionAllowUserInteraction)
                     animations: ^
     {
             _adImage.alpha=0.1f;
     }
                     completion:^(BOOL completed)
                     {
                        NSLog(@"completed=%d", completed);
                        if(completed) {
                            [UIView animateWithDuration:0.1f animations:^{
                                _adImage.alpha=0.0f;
                            }];
                        } else {
                            _adImage.alpha=1;
                        }
                     }];
}

- (void)singleTapGestureCaptured:(UITapGestureRecognizer *)gesture
{
    NSLog(@"Gesture event on view");
    [_adImage.layer removeAllAnimations];
}

Answer 2

这对我在 iOS7.1+ 上非常有用：

self.viewWithTapgesture.backgroundColor = [UIColor colorWithWhite:1.0 alpha:0.01];