I have a project that contains a watchkit extension, this prevents IBDesignable:s from working at all in Xcode 9.2 due to the following error that occurs when Xcode tries to build the project to access the designables:
Build WatchAppTest for IBDesignables
Build target WatchAppTest WatchKit Extension of project WatchAppTest with configuration Debug
Check dependencies
target specifies product type 'com.apple.product-type.watchkit2-extension', but there's no such product type for the 'iphonesimulator' platform
Build failed 2018-01-18, 20:05
The above output is the result of just creating a new app with a watch app using Xcode 9.2 and adding an IBDesignable UIView which is referenced from a storyboard. I believe Xcode is trying to build an aggregate target that it creates by itself for designables but the watch kit extension shouldn't be included.
If I remove the watchkit app then the designable starts working, the designable is only in the app code and has nothing to do with the watch app.
Are there any workarounds? This is quite annoying. It does seem to work in Xcode 9.1