ios - 在屏幕上显示 UIImageView 点击

Question

我试图在用户点击 UIImageView 时显示图像。但是在用户点击 UIImageView 之前，图像不应该显示，几秒钟后图像应该再次消失。有谁知道如何做到这一点？我通读了几个线程，但它们不适用于最新的 Xcode。感谢您的帮助和时间。

更新

好吧，我的代码现在看起来像这样:

    -(void)imageTapped:(UITapGestureRecognizer*)recognizer
    {
        recognizer.view.alpha=0.0;
        ((UIImageView*)recognizer.view).image = [UIImage imageNamed:@"twingo_main.png"];

        [UIView animateWithDuration:1.0 delay:2.0 options:0 animations:^{
            recognizer.view.alpha=1.0;
        } completion:^(BOOL finished) {
            recognizer.view.alpha=0.0;
            ((UIImageView*)recognizer.view).image = nil;
            recognizer.view.alpha=1.0;
        }];
    }

    - (void)viewDidLoad
    {

        UIImageView *hiddenImage = [[UIImageView alloc] initWithFrame:CGRectMake(0, 30, 20, 20)];
        hiddenImage.userInteractionEnabled=YES;
        [hiddenImage addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(imageTapped:)]];
        [self.view addSubview:hiddenImage];

那么，现在我的问题是，我需要如何在 View Controller 中设置 UIImageView？

Answer 1

在您的 UIViewController 的 viewDidLoad 方法中:

    ...

UIImageView *hiddenImage = [[UIImageView alloc] initWithFrame:CGRectMake(0, 30, 20, 20)];
        hiddenImage.userInteractionEnabled=YES;
        [hiddenImage addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(imageTapped:)]];
        [self.view addSubview:hiddenImage];
    ...

UITapGestureRecognizer 处理程序:

-(void)imageTapped:(UITapGestureRecognizer*)recognizer
{
    recognizer.view.alpha=0.0;
    ((UIImageView*)recognizer.view).image = [UIImage imageNamed:@"imageName"];

    [UIView animateWithDuration:1.0 delay:2.0 options:0 animations:^{
        recognizer.view.alpha=1.0;
    } completion:^(BOOL finished) {
        recognizer.view.alpha=0.0;
        ((UIImageView*)recognizer.view).image = nil;
        recognizer.view.alpha=1.0;
    }];
}