AFNetworking UIImageView need scroll to load the images - iphone

Question

I'm inserting images in a UITableViewCell with AFNetworking. The problem is that i need to scroll the table to see the images.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"cell" forIndexPath:indexPath];
Recipe *recipe = [self.fetchedResultsController objectAtIndexPath:indexPath];
cell.textLabel.text = recipe.value;
NSURL *url = [NSURL URLWithString:[BaseURLString stringByAppendingString:recipe.img]];
[cell.imageView setImageWithURL:url];
return cell;
}

Answer 1

There is such a method already implemented by AFNetworking in UIImageView+AFNetworking category.
[imageView setImageWithURLRequest:request placeholderImage:nil success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
blockImageView.image = image;
} failure:nil];
Note that if you pass in nil in success the image is set to the imageview you call the method on. In my case imageView.
So here i guess you can do reload data if you need.

Answer 2

In addition to Peter Segerblom's answer, I would recommend using a __weak reference in place of the __block blockImageVariable variable to avoid a retain cycle.
If you just use __block, the copy of the imageView will never be deallocated and the count will always remain even after the tableView is gone because the pointer is referencing another memory address.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
cell.textLabel.text = #"Cell text";
NSURLRequest *request = [NSURLRequest requestWithURL:imageURL];
__weak UITableView *weakTableView = tableView;
__weak UITableViewCell *weakCell = cell;
__weak UIImageView *weakImageView = cell.imageView;
[cell.imageView setImageWithURLRequest:request
placeholderImage:placeholderImage
success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
weakImageView.image = image;
if ([weakTableView.visibleCells containsObject:weakCell]) {
[weakTableView reloadRowsAtIndexPaths:#[ indexPath ] withRowAnimation:UITableViewRowAnimationNone];
}
} failure:nil];
return cell;
}

Answer 3

#pxpgraphics: I had to replace
NSURLRequest *request = [NSURLRequest requestWithURL:imageURL];
with
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:[NSURL URLWithString:imageURL]];
to prevent a runtime error .

Answer 4

Swift equivalent:
let request = NSURLRequest(URL: book.mediumImageURL)
cell.imageView.setImageWithURLRequest(request, placeholderImage: nil, success: { [weak cell] request, response, image in
if cell {
cell!.imageView.image = image
}
if tableView.visibleCells().bridgeToObjectiveC().containsObject(cell) {
tableView.reloadRowsAtIndexPaths([indexPath], withRowAnimation: .None)
}
}, failure:nil)

Answer 5

I think this is the best code to use:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"SimpleTableItem";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
}
NSURL *url = [NSURL URLWithString:#"http://www.myimageurl.com"]; //Change this URL];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
__weak UITableViewCell *weakCell = cell;
__weak UIImageView *weakImageView = cell.imageView;
[cell.imageView setImageWithURLRequest:request placeholderImage:[UIImage imageNamed:#"granaziOrange"] success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
weakImageView.image = image;
[weakCell setNeedsLayout];
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
NSLog(#"Failed to get image");
}];
return cell;
}

Answer 6

This post has an answer that works: http://jabbleashish.blogspot.com/2013/12/setting-uitableviewcell-imageview-via.html
NSURLRequest *imageRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:#"YOUR_URL"]];
[cell.imageView setImageWithURLRequest:imageRequest placeholderImage:nil
success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image){
NSLog(#"success");
cell.imageView.image = image;
cell.imageView.contentMode = UIViewContentModeScaleAspectFit;
cell.imageView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
[cell setNeedsLayout];// To update the cell {if not using this, your image is not showing over cell.}
}failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error){
NSLog(#"Failure");}
This seems straightforward without having to reload the cell according to index path.

Answer 7

it depends on the cell type - if you have a custom cell with your own UIImageView inside, make sure you DON'T call its outlet "imageView"! Because there is already internal imageView inside every cell.
I solved the problem by renaming linked IBOutlet with something like *myImageView and now everything works fine with code:
[cell.myImageView setImageWithURL:[NSURL URLWithString:#"http://placehold.it/100x100"]];