Create custom UIImage from json data

Question

could you please provide me by sample code for creation a UIImage object with specific width and height programmatically in the code then load an Image in it which supposed to fetch from json (it has to be an image URL).

If I use synchronous network request for loading the picture does it block my UI till loading be completed or not? if so what's the solution?

Thanks in Advance

Answer 1

Pull out the image URL from your json data, download the image, and then use the image as needed.

NSString *imageURL = url from your json string;
NSURL *url = [NSURL URLWithString:imageURL];
UIImageView *imageView = [UIImageView alloc] initWithFrame:CGRectMake(0,0,50,75)];
[yourParentView addSubview: imageView];

dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);

dispatch_async(queue, ^{
    UIImage *image = [UIImage imageWithData: [NSData dataWithContentsOfURL:url]];
    dispatch_sync(dispatch_get_main_queue(), ^{
        imageView.image = image;
        CGRect frame = CGRectMake(imageView.origin.x, imageView.origin.y, image.size.width, image.size.height);
        imageView.frame = frame;
    });
});