Catalyst today, Swift IU tomorrow, Apple is preparing the future of interfaces

Marzipan had to be the star of WWDC. After having unveiled its final name, ” project Catalyst “, Craig Fedherighi him, finally spent just a few minutes. This is done to steal the limelight by Swift UI, a new framework allowing the creation of interfaces for all Apple devices, with a declarative syntax in Swift. Promising ” less code for best apps “, it seems to prefigure the future of application development for the Apple platform.

The declaration of an interface element with Swift UI.

Swift IU, therefore, is a new framework that allows the construction of interfaces, coded ” Swift and Swift “. The whole point of Swift UI lies in its declarative approach : it declares the structure and the arrangement of the interface, it provides textual and graphic elements, and the system takes care of the rest. Spacing, location, mode support dark and Dynamic Type, animations… unless the developers are willing to change, Swift UI automatically provides all the default behaviors.

Swift IU evokes the way in which we can design interfaces on Android, or with frameworks such as React Native. The code is more simple and more clear, but the result is more flexible and resilient, and — most importantly — runs on all devices. Foundations to the interface, the developers can share more code between the different “versions” of an application. The goal is clear : that the same application runs watchOS to macOS via iOS, with the same code, with the exception of some adjustments that are specific to each screen size.

But then, what about Catalyst ? It appears as a transition technology — realize that it is based on a hack that installs a folder system iOS, iOSSupport, within macOS. Swift IU seems to be a solution far more robust, perfectly integrated in Xcode, though still very young. For the moment, Swift IU cohabiting with AppKit on mac os, UIKit on iOS and macOS, and WatchKit for watchOS. For the time being…