While I’ve introduced you quite a number of new features announced in WWDC 2020, let’s step back a bit and check out a useful framework introduced in WWDC 2019. At first glance, it does not look as significant or important as other frameworks, however it consists of a really useful tool when it is needed. That is the LinkPresentation framework, and it provides a handful of built-in functionalities that makes presenting rich links in apps a really simple and straightforward process.
LinkPresentation framework contains mechanisms that parse the website behind a link and fetch metadata necessary in order to display the link in a visually formatted, beautiful manner. In particular, it fetches the title, icon, images, and video metadata, when any of those is provided by the website through the Open Graph protocol.
Fetched metadata can be saved locally for future use, so it’s possible to avoid downloading the exact same data repeatedly. Making the local storage of metadata (caching) a reality is assisted by the custom type that represents metadata programmatically; the LPLinkMetadata class, which is serializable, so it’s easy to create Data objects out of it that can be written locally.
But the above are not the only features available. LinkPresentation also handles the appearance of a visually formatted link by providing a custom view configured based on fetched metadata, and that view also supports user interaction through single tap and long press gestures.
If there’s just one negative point we can spot in the LinkPresentation framework, then that is the fact that it’s built for UIKit (and AppKit on macOS), so integrating it in SwiftUI projects requires some additional work. But no need to worry, as in this post we’ll do exactly this; we’ll build a SwiftUI project where we’ll embed and use the LinkPresentation framework!
LinkPresentation framework works in both iOS and macOS, starting from iOS 13 and macOS 10.15. Besides than fetching metadata for remote links, it’s also possible to deal with links pointing to local files, however that’s not something we’ll discuss in this tutorial. We’ll see all the main features that were presented shortly right above, and on top of that we’ll see how LinkPresentation framework can be combined with the activity view controller in order to share links easily, taking advantage of already cached metadata.
So, keep on reading to find out some cool features of the LinkPresentation framework, but before that, let’s meet the demo application we’re going to build in the next parts of this tutorial!