ios. ScrollView only showing one subview with image - ios

Question

I have a UIScrollView that I want to load a list of images from flickr. Then I want the photos to be displayed like that of the native stock iphone photo app where you scroll through the photos.
Here is my code
- (void)viewDidLoad
{
[super viewDidLoad];
for (int i = 0; i < self.urlArray.count; i++) {
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
UIView *subview = [[UIView alloc] initWithFrame:frame];
[self returnImageFromFlickr:[self.urlArray objectAtIndex:i]];
UIImageView *imageView = self.largePhoto;
[subview addSubview:imageView];
[self.scrollView addSubview:subview];
}
self.scrollView.contentSize = CGSizeMake(self.scrollView.frame.size.width * self.urlArray.count, self.scrollView.frame.size.height);
}
-(void)returnImageFromFlickr:(NSURL *)url {
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
[self.largePhoto setImageWithURLRequest:request placeholderImage:[UIImage imageNamed:#"placeholder.png"] success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
[self.largePhoto setImageWithURL:url placeholderImage:[UIImage imageNamed:#"placeholder.png"]];
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
}];
}
What is happening only the last image is being shown.
I tried your solution as I understood it and got this. This is not brining up a photo. Just a white screen. Plus a warning in the returnImageFromFlicrk method at
[imageView setImageWithURL:url placeholderImage:[UIImage imageNamed:#"placeholder.png"]];
saying
Capturing 'imageView' strongly in this block is likely to lead to a retain cycle
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
/*for (int i = 0; i < self.urlArray.count; i++) {
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
UIView *subview = [[UIView alloc] initWithFrame:frame];
[self returnImageFromFlickr:[self.urlArray objectAtIndex:i]];
UIImageView *imageView = self.largePhoto;
[subview addSubview:imageView];
//subview.backgroundColor = [colors objectAtIndex:i];
[self.scrollView addSubview:subview];
}*/
for (int i = 0; i < self.urlArray.count; i++) {
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
UIImageView *imageView = [[UIImageView alloc] init];
[self returnImageFromFlickr:[self.urlArray objectAtIndex:i] imageview:imageView];
[self.scrollView addSubview:imageView];
}
self.scrollView.contentSize = CGSizeMake(self.scrollView.frame.size.width * self.urlArray.count, self.scrollView.frame.size.height);
}
-(void)returnImageFromFlickr:(NSURL *)url imageview:(UIImageView *)imageView {
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
[imageView setImageWithURLRequest:request placeholderImage:[UIImage imageNamed:#"placeholder.png"] success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
[imageView setImageWithURL:url placeholderImage:[UIImage imageNamed:#"placeholder.png"]];
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
}];
}

Answer 1

You are not setting right parameters to the Scroll content pan that is why all the images you want are not displaying in scrollView. Try updating ScrollView's content pan to fit the width of all images. Like
self.scrollView.contentSize = CGSizeMake(Width, Height);
in this case height will be the hight of single image and width will be (width of single image * total number of images)

Answer 2

You overwrite self.largePhoto, you need set your imageView in returnImageFromFlickr
try this
UIImageView *imageView = [[UIImageView alloc] init];
[self returnImageFromFlickr:[self.urlArray objectAtIndex:i] imageview:imageView];
and
-(void)returnImageFromFlickr:(NSURL *)url imageview:(UIImageView *)imageView {
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
[imageView setImageWithURLRequest:request placeholderImage:[UIImage imageNamed:#"placeholder.png"] success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
[imageView setImage:image];
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
}];
}

Answer 3

All I needed to do was move the code from viewDidLoad to viewDidApear