UIImageView 未显示在 UIScrollView 内部

Question

我有一个 iPhone 应用程序，应该在 UIScrollView 中显示图像。我认为我可以使用 Interface Builder 手动添加 UIScrollView，然后使用 UIImageView 添加图像。

我的做法是否错误？例如，我应该直接将图像添加到 UIScrollView 中吗？

这是我的代码：

- (void)request:(FBRequest *)request didLoad:(id)result {

    //Code for array of photos
    NSArray *photoAlbumArray=(NSArray*)[result valueForKey:@"data"];
    arrayCount=[photoAlbumArray count];

    //check to see if I did that correctly
    [self.label setText:[NSString stringWithFormat:@"%i", arrayCount]];

    //should have an array of photo objects and the number of objects, correct?
    scrollWidth = 0;
    scroller.contentSize=CGSizeMake(arrayCount*scroller.frame.size.width, scroller.frame.size.height);

    for (int i = 0; i < arrayCount;i++) {
        CGRect rect = scroller.frame;
        rect.size.height = scroller.frame.size.height;
        rect.size.width = scroller.frame.size.width;
        rect.origin.x = scroller.frame.origin.x + scrollWidth;
        rect.origin.y = scroller.frame.origin.y;
        UIImageView *scrollImageView = [[UIImageView alloc] initWithFrame:rect];
        id individualPhoto = [photoAlbumArray objectAtIndex:i];
        NSLog(@"%@",individualPhoto);
        NSArray *keys=[individualPhoto allKeys];
        NSLog(@"%@",keys);
        NSString *imageURL=[individualPhoto objectForKey:@"source"];
        //here you can use this imageURL to get image-data and display it in imageView  
        NSURL *url = [NSURL URLWithString:imageURL];
        NSData  *data = [NSData dataWithContentsOfURL:url];
        UIImage *img = [[UIImage alloc] initWithData:data];
        //check to make sure the proper URL was passed
        [self.label setText:imageURL];
        scrollImageView.image = img;
        //I have an imageView next to the UIScrollView to test whether that works - it does.
        imageView.image = img;
        [scroller addSubview:scrollImageView];
        [img release];
        [scrollImageView release];
        scrollWidth += scroller.frame.size.width;
    }

    pageControl.numberOfPages=arrayCount;
    pageControl.currentPage=0;
}

基于此调用：

-(IBAction)showAlbum:(UIButton *)sender
{
    //Go goes here to get an album and display it in the UIScrollView
    [_facebook requestWithGraphPath:@"ALBUM_ID/photos" andDelegate:self];    
}

我在 UIScrollView 左侧的 UIImageView 中显示图像（用于测试目的），并且 UIImageView 工作得很好。所以这就是为什么我想知道我是否在处理这个错误，或者我只是在编码中犯了错误。

你能帮忙吗？因为过去几个小时我一直在研究这个问题，但还没有取得任何进展。

更新 - 这是我根据克里斯的建议所做的。它对我有用，但如果仍然有任何问题，请指出。

        UIImageView *scrollImageView = [[UIImageView alloc] initWithFrame:[scroller bounds]];
        CGRect rect = scrollImageView.frame;
        rect.origin.x = scrollImageView.frame.origin.x + scrollWidth;
        rect.origin.y = scrollImageView.frame.origin.y;
        scrollImageView.frame = rect;

Answer 1

检查您发送到scrollImageView的框架，在这个代码区域：

rect.size.height = scroller.frame.size.height;
rect.size.width = scroller.frame.size.width;
rect.origin.x = scroller.frame.origin.x + scrollWidth;
rect.origin.y = scroller.frame.origin.y;
UIImageView *scrollImageView = [[UIImageView alloc] initWithFrame:rect];

您正在使用滚动条的框架来放置对象，但滚动条的框架将是它在其父视图中的坐标。因此，通过混合不同的坐标集，您很可能将scrollImageView定位在滚动条的内容区域之外。

您可能想改用scroller.bounds，它是滚动条内容区域的矩形。