SwiftUI Multi-platform the Old-school Approach

Alex Nadein
2 min readJan 4, 2022
la vieille école

I decided to write a multi-platform SwiftUI app for this winter holidays. Actually, I wanted to write a separate macOS app. But AppKit is a pain, so I soon switched to the idea of a SwiftUI multi-platform app.

I previously had a limited experience with SwiftUI only in iOS apps. And the first challenge came with List.
I created List from an array of items like this:

Le code

And the result I got:

SwiftUI List rendered on iOS (iPadOS)
SwiftUI List rendered on macOS

iOS result was great, but the macOS version lacks separator lines.

So I modified code with Divider():

Le diviseur

Which produced the next result:

SwiftUI List with dividers rendered on macOS
SwiftUI List with dividers rendered on iOS (iPadOS)

MacOS version looked as I wanted but iOS was messed up.

I also wanted to add UI for deleting rows from my list. So I modified a code like this:


On iOS it resulted in beautiful swipe-to-delete behavior.

But on macOS — it did nothing. So I needed to add delete buttons for rows.

To fix both issues, I decided to add an OS check logic. The usual way of doing it was with UIDevice.current.model. But UIDevice is part of UIKit, and UIKit is not supported by macOS. And I wanted a pure SwiftUI in my app.

At this point, I remembered an OS check trick I used back in Objective-C days. The Preprocessor Directives!

et voilà le résultat

It works and fits the SwiftUI style. That how’s old-school C trick saved the day.
Happy hacking holidays!