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iOS UIScrollview + UIimageviews memory crash

I

igorladessa

macrumors newbie
Original poster
Dec 10, 2012
6
0
I need to scroll over 200 images. I ahve found a tutorial that says that I can over 1000 images with the tutorial code. The tutorial is:

http://soulwithmobiletechnology.blogspot.com.br/2011/05/how-to-load-1000s-of-uiimageview-on.html?m=1

I followed the tutorial, but when I use 100 images aprox..the app crash with memory warning.

My code is here:

http://pastebin.com/BKmsdXxf

I have already with UIIMagenamed, with initWithContentsOfFile

but the problem persist. Pls , help me!
 
I

Ides

macrumors member
Mar 27, 2012
95
0
Well how big are the images you're loading? If they are very large then they will cause memory warnings, if you're loading 100+.
 
PhoneyDeveloper

PhoneyDeveloper

macrumors 68040
Sep 2, 2008
3,114
93
Use a tableview if you can. Otherwise set things up so that only a small number of image views exist at a time. Unload the image views when they scroll off.
 
dejo

dejo

Moderator emeritus
Sep 2, 2004
15,982
452
The Centennial State
igorladessa said:
1,5 mb
Click to expand...
Those are quite large. You might want to consider creating thumbnail versions for display most of the time.

PhoneyDeveloper said:
Use a tableview if you can. Otherwise set things up so that only a small number of image views exist at a time. Unload the image views when they scroll off.
Click to expand...
Yeah, UICollectionView (iOS 6) might be a good solution, if UITableView is not, because it works similar in that cells are reused.
 
I

igorladessa

macrumors newbie
Original poster
Dec 10, 2012
6
0
solved!!

I release all ImageViews and load the current and next imageView, when scrolling!


Code: 
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGPoint scrollOffset=scrollView.contentOffset;
int pagAtual = scrollOffset.x/scroll.frame.size.width;
if(pagAtual != 0) { //always release all imageViews and load the current and next
for(int iCnt = 0; iCnt < [scroll.subviews count]; iCnt++) {
    UIView *viewLiberar = [scroll.subviews objectAtIndex:iCnt];
 if ([viewLiberar isKindOfClass:UIImageView.class]) {
    [viewLiberar removeFromSuperview];
     viewLiberar = nil;
   }
 }
}

if(pageOnScrollView < ((int)scrollOffset.x/scroll.frame.size.width))
 { 

 //load the next page
[self loadNextPage:(pagAtual)];
[self loadNextPage:(pagAtual + 1)];
 }
else if(pageOnScrollView > ((int)scrollOffset.x/scroll.frame.size.width))
  {
  if(pagAtual>0)[self loadNextPage:((int)scrollOffset.x/scroll.frame.size.width)-1];
    }

     pageOnScrollView=scrollOffset.x/scroll.frame.size.width;
      }

It works!
 
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