小编bra*_*dev的帖子

我有一个带有imageView的scrollView.这scrollView是superView的一个子视图,而imageView是一个子视图scrollView.我还有一个标签(在超级视图级别),每隔毫秒从NSTimer接收其text属性的更新值.

问题是:在滚动期间,标签停止显示更新.滚动结束时,标签上的更新将重新开始.更新重启时,它们是正确的; 这意味着label.text值按预期更新,但在滚动时,更新显示在某处覆盖. 无论滚动与否,我都希望在标签上显示更新.

以下是标签更新的实现方式:

- (void)startElapsedTimeTimer {

     [self setStartTime:CFAbsoluteTimeGetCurrent()];
     NSTimer *elapsedTimeTimer = [NSTimer scheduledTimerWithTimeInterval:0.001 target:self selector:@selector(updateElapsedTimeLabel) repeats:YES];
}

- (void)updateElapsedTimeLabel {

    CFTimeInterval currentTime = CFAbsoluteTimeGetCurrent();
    float theTime = currentTime - startTime;

    elapsedTimeLabel.text = [NSString stringWithFormat:@"%1.2f sec.", theTime];
}

谢谢你的帮助.

我正在尝试在imageView中使用单击识别器(也是一个scrollView子项).在Interface Builder中,我只创建并引用了scrollView.滚动工作,但无法识别单击事件(没有记录任何内容).这是代码:

- (void)loadView {
[super loadView];

UIImage *myImage = [UIImage imageNamed:@"img1.jpg"];
imageView = [[UIImageView alloc] initWithImage:myImage];

[myImage release];

// add gesture recognizers to the image view
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleSingleTap:)];

[imageView addGestureRecognizer:singleTap];

[singleTap release];

[imageScrollView setContentSize:CGSizeMake(imageView.frame.size.width, imageView.frame.size.height)];

[imageScrollView addSubview:imageView]; }

- (void)handleSingleTap:(UIGestureRecognizer *)gestureRecognizer {
// single tap handling
NSLog(@"sinlgeTap called"); }

我环顾了几个小时,尝试了很多东西.也许看别人可以帮助更多.谢谢.

我有一个CollectionViewController

- (void)viewDidLoad 
{
   [super viewDidLoad];    
   // assign layout (subclassed below)
   self.collectionView.collectionViewLayout = [[CustomCollectionLayout alloc] init];
}

// data source is working, here's what matters:
- (UICollectionViewCell *)collectionView:(UICollectionView *)cv cellForItemAtIndexPath:(NSIndexPath *)indexPath {
   ThumbCell *cell = (ThumbCell *)[cv dequeueReusableCellWithReuseIdentifier:@"ThumbCell" forIndexPath:indexPath];

   return cell;
}

我还有一个UICollectionViewLayout子类:CustomCollectionLayout.m

#pragma mark - Overriden methods
- (CGSize)collectionViewContentSize
{
    return CGSizeMake(320, 480);
}

- (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect
{
    return [[super layoutAttributesForElementsInRect:rect] mutableCopy];
}

- (UICollectionViewLayoutAttributes *)layoutAttributesForItemAtIndexPath:(NSIndexPath *)indexPath
{
    // configure CellAttributes
    cellAttributes = [super layoutAttributesForItemAtIndexPath:indexPath];

    // random position
    int …