We've covered 3D Touch quite a bit here, we checked out View Controller Previews with Peek and Pop back in Bite #80.

Peek/Pop are great features, it's a shame only our users with the latest hardware can take advantage of them. Today, we'll check out a brand new library that aims to remedy this. It's from Roy Marmelstein and called PeekPop. Let's dive in.

The basic idea of PeekPop is to allow us to support 3D Touch style peeking and popping on devices that don't actually have 3D Touch hardware

The API is quite similar to UIKit's built-in one, let's try it out.

First, we'll register as a delegate, then conform to it:

peekPop = PeekPop(viewController: self)
peekPop?.registerForPreviewingWithDelegate(self, sourceView: collectionView!)

func previewingContext(previewingContext: PreviewingContext, viewControllerForLocation location: CGPoint) -> UIViewController? {
  return self.previewControllerForLocation(location)
}

func previewingContext(previewingContext: PreviewingContext, commitViewController viewControllerToCommit: UIViewController) {
  self.navigationController?.pushViewController(viewControllerToCommit, animated: false)
}

That's it! Neat.

PeekPop will use 3D Touch if available, then fall back on older devices to monitoring signficant changes in a UITouch's majorRadius property. (Pressing harder usually causes this to increase, even on older devices, since often more of the surface area of the finger is in contact with the screen).

More info about PeekPop can be found at git.io/peekpop