Image sorting bug in Scrollview - iPad application - iphone

Question

We are building a catalog app that has 2 rows of sorted images with varying widths but same height. We draw the artwork on scrollview in sorted order (from A to Z) As per attached image.
We search using a alphabetically ordered bar on top that has letters (A to Z) If i touch on letter J the i want the artwork which starts from j comes first. The code we are using is not working well. E.g. clicking on J takes us to A. Will greatly appreciate your help or advice.
Code is as follows:
NSString *newStr = [currentArtworkTitle substringWithRange:NSMakeRange(0,1)];
if([newStr isEqualToString:self.searchString])
if (scrollViewTopRowWidth > scrollViewBottomRowWidth) {
xCordForSortedView = scrollViewTopRowWidth - c - imgForButton.size.width;//self.touchLengthCount;//50 ;// -10//c scrollViewBottomRowWidth
}
else {
xCordForSortedView = scrollViewBottomRowWidth - c - imgForButton.size.width;// self.touchLengthCount;//40;//scrollViewTopRowWidth
}
// For shifting the screen
if(scrollViewTopRowWidth > scrollViewBottomRowWidth){
int tmpMargin = scrollViewTopRowWidth - xCordForSortedView;
if(tmpMargin < 1024)
scrollView.contentSize = CGSizeMake(scrollViewTopRowWidth+1024,scrollView.bounds.size.height);
}
else{
int tmpMargin = scrollViewBottomRowWidth - xCordForSortedView;
if(tmpMargin < 1024)
scrollView.contentSize = CGSizeMake(scrollViewBottomRowWidth+1024,scrollView.bounds.size.height);
}
[scrollView scrollRectToVisible:CGRectMake(xCordForSortedView, 0,scrollView.frame.size.width, scrollView.frame.size.height) animated:YES];

Answer 1

I won't edit your code but I can give you a hint.
Look, when you populate the scrollwiew, by adding an imageview, add also an entry into a NSMutableDictionary (instance variable), so the key will be the A-Z letter, and the value will be the x position of the image. When you finish populating the scrollview, you will have also the dictionary containing the position of all your images (and you need only the x) and the corresponding letter. Now you tap "J" and hit "Search" - you parse your dictionary to fing the object with the key "J" and read it's value. Use this (x) value to set your srollview's contentOffset. Tada!