Stop Using Swift Timers: Use CADisplayLink
Hyperbole, but based in truth
Before we start
Some basic animations, like my loading animation run fine using times to repeat the code blocks and make a UI that looks rather nice to the user.
But this has nothing to do with the framerate of the user’s device, and this may produce a rather horrible drift of the expected animation. In other words, we can do better!
Difficulty: Beginner | Easy | Normal | Challenging
This article has been developed using Xcode 12.2, and Swift 5.3
Keywords and Terminology
CADisplayLink: A timer object that allows your application to synchronize its drawing to the refresh rate of the display
The Repo
I’ve prepared a Repo
The theory
A timer isn’t locked to the screen refreshes, and if we think about the standard 60fps that Apple devices tend to work at, we could have a timer fire right after a screen refresh.
In order to do just that, CADisplayLink calls a method that you define when a redraw happens.
We can compare an implementation of a timer updating at 1 / 60 with an implementation…
