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iOS

Posted by Chris Bedoya
Chris Bedoya
758 Points

Displaying an Image through JSON

Following the BlogReader App example how can I show a thumbnail image when my JSON is nested:

upcoming_releases: [
    {
            id: 2,
            release_name: "Lebron X Low",
            release_price: "165",
            release_colorway: "Raspberry-Red/Blueprint-Court",
            release_date: "2013-09-07T00:00:00.000Z",
            url: "http://obscure-lake-7450.herokuapp.com/upcoming/2",
            images: [
            {
                image_file: {
                    image_file: {
                        url: "https://s3.amazonaws.com/soleresource/uploads/releases/nike-lebron-x-low-raspberry.jpg",
                    thumb: {
                        url: "https://s3.amazonaws.com/soleresource/uploads/releases/thumb_nike-lebron-x-low-raspberry.jpg"
                }
                image_file: {
                    image_file: {
                        url: "https://s3.amazonaws.com/soleresource/uploads/releases/nike-lebron-x-low-raspberry-2.jpg",
                    thumb: {
                        url: "https://s3.amazonaws.com/soleresource/uploads/releases/thumb_nike-lebron-x-low-raspberry-2.jpg"
                }               
            }
        }
    },

I want to show the Image from the FIRST thumb

Thanks.

2 Answers

Aaron Daub
PLUS
Aaron Daub
Courses Plus Student 96 Points
Aaron Daub
Aaron Daub
Courses Plus Student 96 Points 
NSDictionary* JSONObject = ... // serialize JSON
NSString* URLString = [[[[[[[JSONObject objectForKey:@"upcoming_releases"] objectAtIndex:0] objectForKey:@"images"] objectAtIndex:0] objectForKey:@"image_file"] objectForKey:@"thumb"] objectForKey:@"url"];
UIImage* image = [UIImage imageWithContentsOfURL:[NSURL URLWithString:URLString]];
Chris Bedoya
Chris Bedoya
758 Points

I added this to my UpcomingReleaseViewController.m

for (NSDictionary *bpDictionary in blogPostsArray) {
    BlogPost *blogPost = [BlogPost blogPostWithReleaseName:[bpDictionary objectForKey:@"release_name"]];
    blogPost.thumb = [[[[[[JSONObject objectAtIndex:0] objectForKey:@"images"] objectAtIndex:0] objectForKey:@"image_file"] objectForKey:@"thumb"] objectForKey:@"url"];
    [self.blogPosts addObject:blogPost];
}

But I get an error saying that No Known class method for selector 'objectAtIndex'

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    BlogPost *blogPost = [self.blogPosts objectAtIndex:indexPath.row];

    if ( [blogPost.thumb isKindOfClass:[NSString class]]) {
        NSData *imageData = [NSData dataWithContentsOfURL:blogPost.thumbnailURL];
        UIImage *image = [UIImage imageWithContentsOfURL:[NSURL URLWithString:URLString]];;

        cell.imageView.image = image;
    } else {
        cell.imageView.image = [UIImage imageNamed:@"treehouse.png"];
    }

Here I get an error saying Use of undeclared identifier URLString

Aaron Daub
Aaron Daub
Courses Plus Student 96 Points

Where are you declaring JSONObject?

Aaron Daub
Aaron Daub
Courses Plus Student 96 Points

I edited my code. I'm now accessing the top-level JSON object (a dictionary) and getting the object at the @"upcoming_releases" key. After that the code is as before.

Chris Bedoya
Chris Bedoya
758 Points
Chris Bedoya
Chris Bedoya
758 Points

I added this to my UpcomingReleaseViewController.m