Question

我的水平滚动视图中填充了UIImageViews。

我想检测UIImageView上的点击并更改其背景颜色。

不知何故，点击手势不起作用。

但是，当我向滚动视图添加点按手势时，它可以正常工作。 scrollview.background color可以更改。

但我想检测一下它包含的UIImageViews！

UIScrollView* scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 50, 768, 127)];
[scrollView setScrollEnabled:YES];
scrollView.backgroundColor = [UIColor orangeColor];
[scrollView setShowsHorizontalScrollIndicator:NO];
UIImageView *contentOfScrollView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 1, 1130, 125)];
scrollView.contentSize = CGSizeMake(contentOfScrollView.frame.size.width, contentOfScrollView.frame.size.height);

for (int aantal=0; aantal < 6; aantal++) {
    UIImageView *item = [[UIImageView alloc] initWithFrame:CGRectMake(3+(aantal*188), 0, 185, 125)];
    item.backgroundColor = [UIColor yellowColor];
    UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:item action:@selector(imageTapped:)];
    tap.numberOfTapsRequired = 1;
    tap.cancelsTouchesInView=YES;
    item.userInteractionEnabled = YES;
    [item addGestureRecognizer:tap];
    [contentOfScrollView addSubview:item];
}

//UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(imageTapped:)];
//[scrollView addGestureRecognizer:tap];
scrollView.userInteractionEnabled=YES;
scrollView.delaysContentTouches=NO;
[scrollView addSubview:contentOfScrollView];
[self.view addSubview:scrollView];

这是imageTapped函数。

-(void)imageTapped:(UITapGestureRecognizer *)gesture
{
    NSLog(@"tapped!");
    gesture.view.backgroundColor = [UIColor whiteColor];
}

Answer 1

默认情况下，NO的用户互动设置为UIImageView，因此您需要将其设置为YES。您为“item”设置为yes，但不为contentOfScrollView设置。

Answer 2

您的错误在这里：

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:item action:@selector(imageTapped:)];

您需要将目标更改为“self”而不是“item”，然后它不会崩溃。

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(imageTapped:)];

检测UIScrollView内的UIImageView上的点击

2 个答案: