iphone - 仅当用户点击 ImageView 时，才在图像的 UIScrollView 上显示 UIButton Done

Question

我如何编写 UIButton 代码，使其仅在用户点击 UIScrollView 图像时才显示。

 - (void)viewDidLoad

{    
 self.view.backgroundColor = [UIColor blackColor];
  UIScrollView *imageScrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
   imageScrollView.pagingEnabled = YES;
NSInteger numberOfViews = 61;
for (int i = 0; i < numberOfViews; i++) {
    CGFloat xOrigin = i * self.view.frame.size.width;

    UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];

    [myButton addTarget:self action:@selector(dismissView:) forControlEvents:UIControlEventTouchUpInside];

    myButton.frame = CGRectMake(xOrigin, 10, 60, 35);

    [myButton.layer setMasksToBounds:YES];

    [myButton.layer setCornerRadius:10.0f];

    myButton.layer.borderWidth = 2;

    myButton.layer.borderColor = [[UIColor whiteColor] CGColor];

    [myButton setTitle:@"Done" forState:UIControlStateNormal];

    myButton.backgroundColor = [UIColor blackColor];

    NSString *imageName = [NSString stringWithFormat:@"image%d.png", i];
    UIImage *image = [UIImage imageNamed:imageName];
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
    imageView.frame = CGRectMake(xOrigin, 0, self.view.frame.size.width, self.view.frame.size.height);
    [imageScrollView addSubview:imageView];
    [imageScrollView addSubview:myButton];
    [imageView release];
}
imageScrollView.contentSize = CGSizeMake(self.view.frame.size.width * numberOfViews, self.view.frame.size.height);
[self.view addSubview:imageScrollView];
[imageScrollView release];
}

现在它显示在每个 ImageView 上，但我希望它应该仅在点击屏幕时显示 UIButton Done。

编辑:如果我添加

 [imageView addGestureRecognizer: tap];

并启动手势识别器

  UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTap:)];
   tap.numberOfTapsRequired = 1;
  [self addGestureRecognizer:tap];
  [tap release];

那么我如何在句柄点击方法中进行编码，以在用户点击 ImageView 时显示完成按钮

 - (void)handleTap:(UIGestureRecognizer*)tap {

   }

感谢您的帮助。

Answer 1

您需要在 ImageView 上添加手势识别器，而不是在 ViewController 上。

此外，您需要为 ImageView 启用用户交互，如下所示:

imageView.userInteractionEnabled = YES;