- (void)viewWillLayoutSubviews;
{
  [super viewWillLayoutSubviews];
  UICollectionViewFlowLayout *flowLayout = (id)self.collectionView.collectionViewLayout;

if (UIDeviceOrientationIsLandscape([[UIApplication sharedApplication] statusBarOrientation])) {
    flowLayout.itemSize = CGSizeMake(1024.0f, 768.0f);
} else {
    flowLayout.itemSize = CGSizeMake(1024.0f, 768.0f);
}

[flowLayout invalidateLayout]; //force the elements to get laid out again with the new size

visibleItems = [self.collectionView indexPathsForVisibleItems];
self.currentIndexPath = [visibleItems firstObject];
[self.collectionView.collectionViewLayout invalidateLayout];
}

- (IBAction)addToUploadQueque:(id)sender {
NSLog(@"current: %@",self.currentIndexPath);

NSInteger section = [self numberOfSectionsInCollectionView:self.collectionView] - 1;
NSInteger item = [self collectionView:self.collectionView numberOfItemsInSection:section]-1;
NSIndexPath *lastIndexPath = [NSIndexPath indexPathForItem:item inSection:section];
NSIndexPath *firstIndexpath =[NSIndexPath indexPathForItem:0 inSection:0];

NSLog(@"current: %@",lastIndexPath);
if (self.currentIndexPath <= lastIndexPath) {
    NSInteger newLast = [self.currentIndexPath indexAtPosition:self.currentIndexPath.length-1]+1;
    self.currentIndexPath = [[self.currentIndexPath indexPathByRemovingLastIndex] indexPathByAddingIndex:newLast];
    [self.collectionView scrollToItemAtIndexPath:self.currentIndexPath
                                atScrollPosition:UICollectionViewScrollPositionCenteredHorizontally
                                        animated:YES];
}else{
    self.currentIndexPath = [visibleItems firstObject];
    [self.collectionView scrollToItemAtIndexPath:self.currentIndexPath
                                atScrollPosition:UICollectionViewScrollPositionCenteredHorizontally
                                        animated:YES];
}

}

NSInteger item = self.currentIndexPath.item;
NSInteger section = self.currentIndexPath.section;

item++;                                                                    // go to next item
if (item >= [self.collectionView numberOfItemsInSection:section]) {        // if you reached end of section ...
    item = 0;                                                              // ... go to the start of the next section
    section++;
    if (section >= [self.collectionView numberOfSections]) {               // if you reached the end of the data source ...
        // all done, so set section to zero to go back to beginning, e.g.  // ... then you're done
        section = 0;
    }
}
self.currentIndexPath = [NSIndexPath indexPathForItem:item inSection:section]; // otherwise, this is your new NSIndexPath

for (NSIndexPath *indexPath in self.collectionView.indexPathsForVisibleItems) {
    // if the cell has some visual indication to reflect upload has been initiated,
    // do that here

    // do your asynchronous upload here, where the completion block dispatches
    // updates to the cell/collectionView (to reflect that the individual upload
    // is done)
}