Reuse cells of a scroll view - iphone

Question

I am using a scrollview to display various items in a horizontal fashion.
How can I "reuse the cells" to conserve memory:
Edit: Apologies for not being clear. I plan to place a few labels and and another ImageView inside each ImageView so I am keen to reuse this each time instead of instantiating new items each time. e.g. change the image's and update the labels instead of re-create it.
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[super viewDidLoad];
// load all the images from our bundle and add them to the scroll view
// NSUInteger i;
for (int i = 0; i <= 150; i++)
{
NSString *imageName = #"tempImage.jpg";
UIImage *image = [UIImage imageNamed:imageName];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
// setup each frame to a default height and width, it will be properly placed when we call "updateScrollList"
CGRect rect = imageView.frame;
rect.size.height = kScrollObjHeight;
rect.size.width = kScrollObjWidth;
imageView.frame = rect;
imageView.tag = i; // tag our images for later use when we place them in serial fashion
[self.bestSellScrollView addSubview:imageView];
[imageView release];
}
[self layoutScrollImages]; // now place the photos in serial layout within the scrollview
}
- (void)layoutScrollImages
{
UIImageView *view = nil;
NSArray *subviews = [self.bestSellScrollView subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 0;
for (view in subviews)
{
if ([view isKindOfClass:[UIImageView class]] && view.tag > 0)
{
CGRect frame = view.frame;
frame.origin = CGPointMake(curXLoc, 0);
view.frame = frame;
curXLoc += (kScrollObjWidth);
}
}
// set the content size so it can be scrollable
[self.bestSellScrollView setContentSize:CGSizeMake((150 * kScrollObjWidth),
[self.bestSellScrollView bounds].size.height)];
}

Answer 1

If you mean like what happens with respect UITableViewCell in a UITableView, then its not possible in the horizontal scroller.
The reusable cells property for a table view is provided by the system and it not applicable for horizontal scroller.
You have to write on your own logic in order to achieve it, perhaps! Its a good question though. Will be tuned to other answers just in case if anything is possible.

Answer 2

If you mean you'd like to keep the UIImageView(s) where they are in the scrollview, but you'd like to change the UIImage that they show, try something like this:
-(void)changeImageViewWithTag:(NSInteger)aTag toImage:(UIImage *)anImage
{
UIImageView *theView = [self.bestSellScrollView viewWithTag:aTag];
if (theView)
{
[theView setImage:anImage];
}
}

Answer 3

I am assuming that you intend to reuse the UIImageView cell instances in the UIScrollView.
I hope that Daniel Tull's implementation may be helpful--
https://github.com/danielctull/DTGridView
You may like to see an Apple sample code on UIScrollView as well(I don't have the link, but u can easily find it on the web)
Thanks!
Ishank