Swift version: 5.6
Swift makes it easy to write special code that should be executed only in the iOS Simulator. This is helpful to test situations where the simulator and devices don't match, for example testing the accelerometer or camera.
If you want certain code to be run only in the iOS simulator, you should use this:
#if targetEnvironment(simulator)
// your code
#endif
Any code between the #if
and #endif
won't even exist when the app is run on devices, so it has zero performance impact. If you want to specify alternate code that should only be run on devices (and never on the simulator) you should use #else
, like this:
func updateMotion() {
#if targetEnvironment(simulator)
// we're on the simulator - calculate pretend movement
if let currentTouch = lastTouchPosition {
let diff = CGPoint(x: currentTouch.x - player.position.x, y: currentTouch.y - player.position.y)
physicsWorld.gravity = CGVector(dx: diff.x / 100, dy: diff.y / 100)
}
#else
// we're on a device – use the accelerometer
if let accelerometerData = motionManager.accelerometerData {
physicsWorld.gravity = CGVector(dx: accelerometerData.acceleration.y * -50, dy: accelerometerData.acceleration.x * 50)
}
#endif
}
BUILD THE ULTIMATE PORTFOLIO APP Most Swift tutorials help you solve one specific problem, but in my Ultimate Portfolio App series I show you how to get all the best practices into a single app: architecture, testing, performance, accessibility, localization, project organization, and so much more, all while building a SwiftUI app that works on iOS, macOS and watchOS.
Sponsor Hacking with Swift and reach the world's largest Swift community!
Available from iOS 7.0 – see Hacking with Swift tutorial 26
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
Link copied to your pasteboard.