How To Insert Item in UIcollectionview after downloading data - ios

Question

Friends here I am using UICollectionview to show images but my images are coming from web services.
now the problem is that I got all data from the net but how I can insert item in UICollectionview.
I know insertItemAtIndexPath method but don't know where and how to use it.
Please help me out.
Thanks in advance.

Answer 1

You could use the delegate pattern in order to download your data.
The delegate will prevent the class that implements the protocol that the download is finished so you can load data through the method called with [YouCollectionView reloadData]
and to display your image, your collectionView could be based on an array, so for example, the delegate could send a array with your image/url.
/*! This delegate method is called when the items have been downloaded. They're then stored into an array.*/
- (void)didDownloadItems:(NSMutableArray*)responseArray{
_imgArray = responseArray;
[yourCollectionView reloadData];
}
and then in your : (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"Cell";
UICollectionViewCell *cell = [yourCollectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];
// Retrieve the img
UIImage *img = [_imgArray objectAtIndex:indexPath.row];
//do your stuff with the img
return cell;
}