UITapGestureRecognizer 未触发以编程方式创建的 UIImageView

Question

我正在使用 XCode 4.5.1。

我在 .h 文件和 .m 文件的开头添加了<UIGestureRecognizerDelegate>

@interface FirstViewController ()

@property (nonatomic, strong) UIImageView *img1;

@end

然后在viewDidLoad 中，以编程方式创建UIImageView

self.img1 = [[UIImageView alloc] initWithFrame:CGRectMake(50, -30, 44, 44)];
[self.img1 setImage:[UIImage imageNamed:@"image1.png"]];
[self.img1 setAlpha:0.8];
[self.img1 setHidden:NO];
[self.img1 setUserInteractionEnabled:YES];
[self.img1 setTag:901];

然后

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(guessTapObject:)];
tap.numberOfTapsRequired = 1;
tap.numberOfTouchesRequired = 1;
tap.delegate = self;

[self.img1 addGestureRecognizer:tap];

[self.view addSubview:self.img1];
[self.view bringSubviewToFront:self.img1];

最后

- (void)guessTapObject:(UITapGestureRecognizer *) gesture
{
    // guessing the image
    UIImageView *tapImageView = (UIImageView*) gesture.view;
    NSLog(@"Gesture Tag: %d", tapImageView.tag);
}

我有 4 个不同的图像，并如上所述以编程方式创建它们。并应用动画将它们从上到下移动。

我希望当用户点击图像时，它应该动画并消失（我知道那个代码）。但是代码没有触发点击事件。我将断点放在guessTapObject 函数的开头，但永远不要去那里。

在UITapGestureRecognizer 声明处，调试显示guessTapObject 附加到识别器以执行点击操作。

请帮忙为什么点击事件没有触发它的选择器方法？？？

提前感谢您的帮助。

---

编辑： 我还尝试使用 for 循环为每个图像视图分别设置手势识别器

for (UIView * view in self.view.subviews) {
    if (view.tag > 900){
        UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(guessTapObject:)];
        tap.numberOfTapsRequired = 1;
        tap.numberOfTouchesRequired = 1;
    //    tap.delegate = self;
        [view addGestureRecognizer:tap];
        NSLog(@"tapView: %@", tap.view);
        NSLog(@"tap: %i", tap.enabled);
    }
}

Answer 1

我遇到了类似的问题..确保 userInteraction 的 imageView 设置为 true..

imageView.userInteractionEnabled = YES;

它对我有用！

Answer 2

检查一下
将以下代码添加到您的视图控制器

• 在 viewController.h 文件中
  

  @property (nonatomic, strong) UIImageView *img1;
  @property (nonatomic, strong) UIImageView *img2;
  @property (nonatomic, strong) UIImageView *img3;
  

• 在 viewController.m 文件中
  viewDidLoad 方法内部
  

  // Init Image 1 
  self.img1 = [[UIImageView alloc] initWithFrame:CGRectMake(50, 30, 44, 44)];
  [self.img1 setImage:[UIImage imageNamed:@"image1_name.jpg"]];
  [self.img1 setAlpha:0.8];
  [self.img1 setHidden:NO];
  [self.img1 setUserInteractionEnabled:YES];
  [self.img1 setTag:901];
  
  // Init Image 2
  self.img2 = [[UIImageView alloc] initWithFrame:CGRectMake(100, 30, 44, 44)];
  [self.img2 setImage:[UIImage imageNamed:@"image2_name.jpg"]];
  [self.img2 setAlpha:0.8];
  [self.img2 setHidden:NO];
  [self.img2 setUserInteractionEnabled:YES];
  [self.img2 setTag:902];
  
  // Init Image 3
  self.img3 = [[UIImageView alloc] initWithFrame:CGRectMake(50, 130, 44, 44)];
  [self.img3 setImage:[UIImage imageNamed:@"image3_name.jpg"]];
  [self.img3 setAlpha:0.8];
  [self.img3 setHidden:NO];
  [self.img3 setUserInteractionEnabled:YES];
  [self.img3 setTag:903];
  
  // Add Images to view
  [self.view addSubview:self.img1];
  [self.view bringSubviewToFront:self.img1];
  
  [self.view addSubview:self.img2];
  [self.view bringSubviewToFront:self.img2];
  
  [self.view addSubview:self.img3];
  [self.view bringSubviewToFront:self.img3];
  
  // Set Tap Gesture to each image of view
  for (UIView * view in self.view.subviews) {
    if (view.tag > 900){
       UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] 
                                        initWithTarget:self 
                                        action:@selector(guessTapObject:)];
       tap.numberOfTapsRequired = 1;
       tap.numberOfTouchesRequired = 1;
       [view addGestureRecognizer:tap];
       NSLog(@"tapView: %@", tap.view);
       NSLog(@"tap: %i", tap.enabled);
    }
  }
  

确保在 for 循环之前添加图片（使用子视图数组添加 TapGesture）

Answer 3

我通过在视图上应用手势来解决问题，而不是单独的每个图像视图。

[self.view addGestureRecognizer:tap];

然后在处理程序/选择器guessTapObject 函数中，我使用了这个

CGPoint tapLocation = [gesture locationInView:self.view]; // gives the tap coordinates
for (UIView * view in self.view.subviews) { // gives view by iterating on each subview
    CGRect dropRect = [[[view layer] presentationLayer] frame]; // specific way of getting the frame with respect to its layer

    if(CGRectContainsPoint(dropRect, tapLocation)){ // checks for tap in the boundaries of view frame
        if (view.tag > 900) // my specific view
             // done what i want to do with that specific one
             // as i removed it from my superview
        }
    }
}