Bizarre UIScrollView behavior - iphone

Question

I've got myself totally baffled with this scrollview. For some reason, on the third pass of this loop, an extra two UIImageViews get added as subviews. I assume i'm addressing bad memory, or something to that effect, but I can't figure out where it is coming from for the life of me.
Here's the code:
scrollview=[[[UIScrollView alloc] initWithFrame:CGRectMake(x, y+40, 300, 225)] retain];
NSArray *chunks=[lesson.photoString componentsSeparatedByString:#"|"];
ALAssetsLibrary *assetLibrary;
__block CGRect workingFrame = scrollview.bounds;
__block UIImageView *imageview=nil;
workingFrame.origin.x = 0;
NSLog(#"Chunks: %d\n",[chunks count]);
for(NSString *url in chunks) {
//
if(url && [url length])
{
NSURL *asseturl = [NSURL URLWithString:url];
assetLibrary = [[[ALAssetsLibrary alloc] init] autorelease];
[assetLibrary assetForURL:asseturl
resultBlock:^(ALAsset *myasset)
{
UIView *sub=[[UIView alloc] initWithFrame:workingFrame];
imageview=[[UIImageView alloc] initWithImage:[UIImage imageWithCGImage:[[myasset defaultRepresentation] fullScreenImage]]];
[imageview setContentMode:UIViewContentModeScaleAspectFit];
imageview.frame = sub.bounds;
[sub addSubview:imageview];
[imageview release];
UIButton *imgfull=[UIButton buttonWithType:UIButtonTypeCustom];
[imgfull setFrame:sub.bounds];
imgfull.backgroundColor=[UIColor clearColor];
[imgfull addTarget:self action:#selector(imageViewToFullScreen) forControlEvents:UIControlEventTouchUpInside];
[sub addSubview:imgfull];
[imgfull release];
[scrollview addSubview: sub];
[sub release];
NSLog(#"%#",[scrollview subviews]);
workingFrame.origin.x = workingFrame.origin.x + workingFrame.size.width;
[scrollview setContentSize:CGSizeMake(workingFrame.origin.x, workingFrame.size.height)];
if(scrollview.contentSize.width>300)
[scrollview flashScrollIndicators];
}
failureBlock:^(NSError *myerror){
NSLog(#"Failure - %#",[myerror localizedDescription]);
}
];
}
}
[scrollview setPagingEnabled:YES];
[self.view addSubview:scrollview];
Here's the output:
2011-05-04 11:53:00.331 AppName[24896:207] Chunks: 4
2011-05-04 11:53:00.369 AppName[24896:207] (
"<UIView: 0x6685960; frame = (0 0; 300 225); layer = <CALayer: 0x6685990>>"
)
2011-05-04 11:53:00.394 AppName[24896:207] (
"<UIView: 0x6685960; frame = (0 0; 300 225); layer = <CALayer: 0x6685990>>",
"<UIView: 0x642db00; frame = (300 0; 300 225); layer = <CALayer: 0x6420c80>>"
)
2011-05-04 11:53:00.426 AppName[24896:207] (
"<UIView: 0x6685960; frame = (0 0; 300 225); layer = <CALayer: 0x6685990>>",
"<UIView: 0x642db00; frame = (300 0; 300 225); layer = <CALayer: 0x6420c80>>",
"<UIImageView: 0x666e3d0; frame = (292 1; 7 223); alpha = 0; opaque = NO; autoresize = LM; userInteractionEnabled = NO; layer = <CALayer: 0x666e400>>",
"<UIImageView: 0x6605490; frame = (1 217; 149 7); opaque = NO; autoresize = TM; userInteractionEnabled = NO; animations = { opacity=<CABasicAnimation: 0x6686ff0>; }; layer = <CALayer: 0x6664280>>",
"<UIView: 0x6686c30; frame = (600 0; 300 225); layer = <CALayer: 0x6686c60>>"
)
2011-05-04 11:53:00.439 AppName[24896:207] (
"<UIView: 0x6685960; frame = (0 0; 300 225); layer = <CALayer: 0x6685990>>",
"<UIView: 0x642db00; frame = (300 0; 300 225); layer = <CALayer: 0x6420c80>>",
"<UIImageView: 0x666e3d0; frame = (292 1; 7 223); alpha = 0; opaque = NO; autoresize = LM; userInteractionEnabled = NO; layer = <CALayer: 0x666e400>>",
"<UIView: 0x6686c30; frame = (600 0; 300 225); layer = <CALayer: 0x6686c60>>",
"<UIImageView: 0x6605490; frame = (1 217; 99 7); opaque = NO; autoresize = TM; userInteractionEnabled = NO; animations = { opacity=<CABasicAnimation: 0x6648d60>; }; layer = <CALayer: 0x6664280>>",
"<UIView: 0x6673f90; frame = (900 0; 300 225); layer = <CALayer: 0x6673fc0>>"
)
EDIT: I should also mention that I've NSLog'd sub, and it produces the results I'd expect (1 imageview, 1 button per trip through the loop). I should also mention, that as far as I know I have no imageviews of the dimensions shown from the scrollview logging (99x7 or 7x223) anywhere in my app.
EDIT 2: A bit further information: I switched the add line to [scrollview addSubview:nil]; and I'm still seeing two imageviews being added on the third pass of the loop. Also, scrollview isn't accessed from anywhere else outside the posted code section.
EDIT 3: Figured out out. I'm flashing the scrollbars too early, which is mucking with the order of the subviews within the scrollview.

Answer 1

Are these the scroll view indicators flashing?

Answer 2

If no unusual images actually appear on your scroll view, you can assume those subviews are managed internally by UIScrollView and you should ignore them. Scroll indicators, perhaps.

Answer 3

Actually These extra two images are the uiscrollindicator images that are vertical scroll indicator and horizontal scroll indicator with tag 0 That are added by UIScrollview Automatically , if you add UIIMageViews to the ScrollView make sure to assign tag greater than zero, or use some other technique , so that you can retrieve your UIIMageViews by tag greater than zero..