A reusable, zoomable image gallery for iOS using the datasource and delegate patterns. Handles device orientation changes and memory warnings.

Features

GVPhotoBrowser is extremely flexible. Where other photo browsers expect an array of UIImage objects or maybe NSURL's, GVPhotoBrowser instead uses the datasource pattern and will ask you to provide it with a UIImageView for every image. It's very similar to UITableView.

GVPhotoBrowser consists of GVPhotoBrowser, a UIScrollView subclass to be used directly in your own view controllers; and GVPhotoBrowserViewController which you can subclass, and which will take care of creating the GVPhotoBrowser with the correct frame and auto resizing masks, and the delegate and datasource set to itself. Again, very similar to UITableView and UITableViewController.

It does not come with title or UIPageControl handling. Adding a page control is easily done in your view controller, use the delegate to set the current page. And if you want to show titles or captions, this can be done by customizing the UIImageView that your datasource returns. These design decisions are what make GVPhotoBrowser so flexible.

Example

An example of using the photo browser to load remote images using SDWebImage (something like SDWebImage-ProgressView would be a very good fit as well):

@interface ViewController : GVPhotoBrowserViewController
@property (strong, nonatomic) NSArray *imageUrls;
@end

@implementation ViewController

#pragma mark - GVPhotoBrowserDataSource

- (NSUInteger)numberOfPhotosInPhotoBrowser:(GVPhotoBrowser *)photoBrowser {
    return [self.imageUrls count];
}

- (UIImageView *)photoBrowser:(GVPhotoBrowser *)photoBrowser customizeImageView:(UIImageView *)imageView forIndex:(NSUInteger)index {
    NSURL *url = self.imageUrls[index];
    [imageView setImageWithURL:url];
    return imageView;
}

#pragma mark - GVPhotoBrowserDelegate

- (void)photoBrowser:(GVPhotoBrowser *)photoBrowser didSwitchToIndex:(NSUInteger)index {
    self.title = [NSString stringWithFormat:@"%i of %i", index+1, [self.imageUrls count]];
}

If you don't want to use the GVPhotoBrowserViewController subclass, you can just use GVPhotoBrowser directly.

@interface ViewController : UIViewController <GVPhotoBrowserDataSource, GVPhotoBrowserDelegate>
@property (weak, nonatomic) IBOutlet GVPhotoBrowser *photoBrowser;
@end