Image from bundle loads ok in SwiftUI but not in UIKit

Question

I have developed a framework that consists of some colors in the asset catalogue. I packaged it in the cocoapod and integrated in another project where I try to access the assets from the framework. Everything works correctly as long as I'm in the SwiftUI domain, if I try to do exactly the same thing in UIKit, suddenly the images are no longer available (or at least this is what the UIImage constructor claims).

func testAssetSDKBundleAccess() {
    let bundle = Assets.bundle
    XCTAssertNotNil(bundle, "The Assets.bundle should not be nil")
    XCTAssertNotNil(Image("Switzerland", bundle: bundle))
    XCTAssertNotNil(UIImage(named: "Switzerland", in: bundle, compatibleWith: nil)) <- XCTAssertNotNil failed
}

When I run the same test case in my asset framework - it passes fine. Looks like something UIKit specific, but it got me puzzled for a couple of days now and I can't figure it out.

Xcode 13.2.1, Swift version 5

Answer 1

This turned out to be a problem connected with cocoapods. My assets framework exposes it's bundle with Assets.bundle and inside there you have to check what is available to you - when building from source you access the bundle in a different way than when using xcframework. So, our bundle access code tried one way, when it failed it tried the other. We changed the order and suddenly it started working - I don't understand why it works now but I take it. The correct order below:

public static let bundle: Bundle = {
    let bundleName = "MyFramework"
    
    /* Bundle should be present here when linked as pod dependency. */
    let podBundle = Bundle(for: MyFramework.self)
    if let path = podBundle.path(forResource: bundleName, ofType: "bundle"), let bundle = Bundle(path: path) {
        return bundle
    }
    
    /* Bundle should be present here when running local tests or linked as xcframework. */
    if let bundle = Bundle(identifier: "com.app.example.\(bundleName)") {
        return bundle
    }
    
    fatalError("Unable to load bundle named \(bundleName)")
}()