Migrating to a single-target watchOS app
Adopt the single-target configuration to simplify your project and avoid ambiguity about where to store resources and apply entitlements.
Overview
A watchOS app has one of the following project configurations:
- Dual target
Contains a watchOS app target and a separate WatchKit extension target that holds the app’s core logic and resources.
- Single target
Contains only a watchOS app target, which holds all of the app’s logic and resources.
Single-target apps have a simpler project configuration and avoid ambiguity about where to store resources and apply entitlements.
When the minimum deployment target is watchOS 9.2 or later, building a dual-target app with Xcode produces an error, and prompts you to migrate to a single-target app using the built-in migrator. Building a single-target app that still uses the WKExtension APIs produces warnings that guide you to replace the APIs with the WKApplication counterparts. If you have a dual-target watchOS app, migrate it to a single-target app.
Convert a dual-target app to a single-target app
Follow these steps to convert your app:
Create a complete backup of your project before you start, so you can roll back if something goes wrong.
In the Project navigator, select your project, then choose Xcode > Editor > Validate Settings.
Select the “Project
<your project>- Upgrade<your watchOS app target>to a single-target watch app” checkbox if it’s unselected, then choose Perform Changes.If you use storyboards, update the class module for each interface controller to the watchOS app module. Select an interface controller, choose View > Inspectors > Identity, then set the Class field in the Custom Class section. Repeat for each interface controller.
Remove any files that only apply to the WatchKit extension, such as the extension’s information property list.
Reorganize the groups and files in the Project navigator to clean up your project.
Run the project on an Apple Watch to verify everything works.
The second step removes the WatchKit extension target and moves its source code and resources to the watchOS app target. At the code level, it replaces WKExtension and WKExtensionDelegate with WKApplication and WKApplicationDelegate.
It also updates the watchOS app target’s information property list as needed. For example, if your watchOS app has a complication, it moves the complication controller class, which is specified with CLKComplicationPrincipalClass, to the watchOS app target, and adds the CLKComplicationPrincipalClass and CLKComplicationSupportedFamilies entries to the watchOS app’s information property list.