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JTSImageViewController

An interactive iOS image viewer that does it all: double tap to zoom, flick to dismiss, et cetera.

Pull Requests

Pull requests are welcome, but should be submitted on the dev branch. Exceptions will be made for critical bug fixes.

What Does it Do?

JTSImageViewController is like a “light box” for iOS. It’s similar to image viewers you may have seen in apps like Twitter, Tweetbot, and others. It presents an image in a full-screen interactive view. Users can pan and zoom, and use Tweetbot-style dynamic gestures to dismiss it with a fun flick.

Screenshot

How Does it Work?

Usage is pretty simple, though there are some cool options and delegate methods if you need them. Here’s what your simplest implementation might look like:

- (void)someBigImageButtonTapped:(id)sender {

    // Create image info
    JTSImageInfo *imageInfo = [[JTSImageInfo alloc] init];
    imageInfo.image = YOUR_SOURCE_IMAGE;
    imageInfo.referenceRect = self.bigImageButton.frame;
    imageInfo.referenceView = self.bigImageButton.superview;

    // Setup view controller
    JTSImageViewController *imageViewer = [[JTSImageViewController alloc]
                                           initWithImageInfo:imageInfo
                                           mode:JTSImageViewControllerMode_Image
                                           backgroundStyle:JTSImageViewControllerBackgroundStyle_ScaledDimmedBlurred];

    // Present the view controller.
    [imageViewer showFromViewController:self transition:JTSImageViewControllerTransition_FromOriginalPosition];
}

That’s it.

Extras and Options

  • Image Downloads: If you don’t have the source image already, just use the imageURL property when setting up the JTSImageInfo instance. JTSImageViewController will handle downloading the image for you.

  • Background Styles: Choose between a scaled-and-dimmed style or a scaled-dimmed-and-blurred background style. The latter is like the one used in Tweetbot.

  • Alt-Text Mode: Need to show the alt text for an image? JTSImageViewController includes an alternate mode that shows a full-screen, centered text view using the same style as the image mode.

  • Handle Long-Presses: Implement an interactionsDelegate to respond to long presses on the image, or to temporarily disable user interactions (comes in handy if you show an overlay that could cause gesture conflict).

License

MIT License, see the included file.