I decided to implement a few views using SwiftUI in my app. The app is backwards compatible to iOS 12.
Everything works perfectly until I run it on an iOS 12 device. The app crashes immediately and the warning I get says SwiftUI cannot be loaded.
dyld: Library not loaded: /System/Library/Frameworks/SwiftUI.framework/SwiftUI
Referenced from: /var/containers/Bundle/Application/MyApp.app/MyApp
Reason: image not found
I'm using @available(iOS 13.0, *) in all the correct places and there are no compiler warnings and the app runs perfectly on iOS 13
How can I get this to work for iOS 12?
Turns out this is a known issue and apple introduced a new build setting flag to handle it
Apps containing SwiftUI inside a Swift package might not run on
versions of iOS earlier than iOS 13. (53706729)
Workaround:
When back-deploying to an OS which doesn't contain the SwiftUI framework,
add the -weak_framework SwiftUI flag to the Other Linker Flags setting
in the Build Settings tab. See Frameworks and Weak Linking for more
information on weak linking a framework. This workaround doesn't apply
when using dynamically linked Swift packages which import SwiftUI.
Adding -weak_framework SwiftUI to Other Linker Flags fixed my issue
You can also mark SwiftUI.framwerk as optional in Build Phases. Detailed Instruction below.
- Select your project file in the Xcode navigator.
- Select your app target (or whichever target you're using SwiftUI
from).
- Select the “Build Phases” tab, then “Link Binary With Libraries” section.
- Click the + button under the list that appears.
- Type “SwiftUI” into the search field of the popup sheet, select
“SwiftUI.framework,” and click “Add.”
- On the new row in the table, click the “Required” popup button in the last column. Change the
value to “Optional.”
So sorry, but I don't think SwiftUI Will work on older versions then iOS 13. Found this stack link if you want more details Is SwiftUI backwards-compatible with iOS 12.x and older?
