Question

我添加了程序化的子视图。对于每个子视图，我正在添加一个手势重新识别器：

UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
    imageView.frame = CGRectMake((position*1024)+200,0,image.size.width,image.size.height);
    UITapGestureRecognizer *singleFingerTap = [[UITapGestureRecognizer alloc]
                                               initWithTarget:self action:@selector(singleFingerTap:)];
    singleFingerTap.numberOfTapsRequired = 1;
    [imageView addGestureRecognizer:singleFingerTap];
    [singleFingerTap release];

但是点击没有响应我如何验证手势是否已将其添加到子视图？

Answer 1

在代码后添加：

NSLog(@"imageView.gestureRecognizers: %@", [imageView.gestureRecognizers description]);

如果您已正确添加了gestureRecognizers，它会将每个描述打印到控制台。如果没有，它将在控制台中显示（NULL）或空数组。

您还可以设置手势识别器委托：

[singleFingerTap setDelegate:self];

然后添加委托方法并设置断点以确保它被调用：

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {
    NSLog(@"gestureRecognizerShouldBegin: called");
    return YES;
}

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

如何知道UITapGestureRecognizer是否已添加到子视图中

1 个答案: