檢測UIScrollView內的UIImageView上的點擊

Question

我有一個填充UIImageViews的水平滾動視圖。

我想檢測UIImageView上的點擊並更改其背景顏色。

不知何故，敲擊手勢不起作用。

但是，當我向滾動視圖添加點按手勢時，它可以正常工作。 scrollview.background color可以更改。

但我想檢測它包含的UIImageViews的點擊！

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];

這是imageTapped函數。

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

Answer 1

對於UIImageView ，默認情況下用戶交互設置為NO ，因此您需要將其設置為YES 。 您為“item”設置為yes，但不為contentOfScrollView設置為yes。

Answer 2

你的錯誤在這里：

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

您需要將目標更改為“self”而不是“item”，然后它不會崩潰。

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