I've been messing around with converting my app icons to use Icon Composer. My app has multiple app icons, but I've noticed that I cant seem to set .icon files using the alternate app icon api. I believe this is due to the requirement that alternate app icons live in the Assets Catalogue but .icon files go anywhere in your project. Is there any plan to support this? Or am i missing something?
I was able to successfully set a .icon file for the primary app icon.
If your app needs to support "old" style iOS 18 icons and new glass icons for iOS 26, you can do this as well as support alternate icons. Please see my post (and the next) at https://developer.apple.com/forums/thread/787576?answerId=846523022#846523022
Below issues are fixed in beta3
@mehulFunnmedia I've been using glass alternate icons since beta 1. Can you clarify what's changed in Xcode beta 3?
It would be great to have a simple way to enforce alternate icons for older macOS versions in XCode while using the Icon Composer generated ones for Tahoe.
Prior to Xcode 26 beta 4, one could add an App Icon set to Assets for legacy macOS versions and use the an Icon Composer variant in the project root for Tahoe. Enabling "Include all app icon assets" under target settings also helped according to some. This option is now gone, Beta 4 insists on populating the Assets.car with Icon Composer generated variants, disregarding the App Icon provided in Assets.
The App Icon variant in Assets makes its way to a .incs file in the app bundle's Contents/Resources folder, but that is not used by macOS anymore and is there for some compatibility purposes. The Assets.car file (which matters) only contains the png variants generated by Icon Composer.
Several app developers (especially with icon designs that try to follow the curvature of the standard icon size) are struggling with this issue.
I posted this as a new separate question, maybe an Apple engineer will respond: https://developer.apple.com/forums/thread/794485