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iOS

Posted by Christian Opalinski
Christian Opalinski
6,853 Points

Code Challenge: Connecting to an API Challenge Task 1

Can some one please help me with this code? I'm not seeing what I'm doing wrong.

Any help is much appreciated!

Challenge is: It looks like we've written a bug. When we set our image on the image view, it's not working quite right. Fix this by setting the image on the image view using the main queue.

import "AwesomeViewController.h"

@implementation AwesomeViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    NSURL *url = [NSURL URLWithString:@"http://blog.teamtreehouse.com/wp-content/themes/treehouse/images/logo-blog2x.png"];

    NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
    NSURLSession *session = [NSURLSession sharedSession];

    NSURLSessionDownloadTask *task = [session downloadTaskWithRequest:request 
                     completionHandler:^(NSURL *location, NSURLResponse *response, NSError *error) {
        NSData *data = [[NSData alloc] initWithContentsOfURL:location];
        UIImage *image = [[UIImage alloc] initWithData:data];
    dispatch_async(dispatch_get_main.queue(),^{self.imageView.image = image;});
    }];

    [task resume];
}

@end

1 Answer

Daniel Konrad
Daniel Konrad
Courses Plus Student 5,973 Points

Hey Christian,

you almost did it right, there is just a little typo in your code.

If you put "dispatch_get_main_queue" instead of "dispatch_get_main.queue" it will pass the challenge...

It should look like the following:

import "AwesomeViewController.h"

@implementation AwesomeViewController

  • (void)viewDidLoad { [super viewDidLoad];

    NSURL *url = [NSURL URLWithString:@"http://blog.teamtreehouse.com/wp-content/themes/treehouse/images/logo-blog2x.png"];

    NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url]; NSURLSession *session = [NSURLSession sharedSession];

    NSURLSessionDownloadTask *task = [session downloadTaskWithRequest:request completionHandler:^(NSURL *location, NSURLResponse *response, NSError *error) { NSData *data = [[NSData alloc] initWithContentsOfURL:location]; UIImage *image = [[UIImage alloc] initWithData:data];

            dispatch_async(dispatch_get_main_queue(), ^{
    self.imageView.image = image;
});

    }];

    [task resume]; }

@end

Cheers Daniel