ios - WatchKit: unable to find interface controller class

Question

I tried adding an interface controller to a storyboard, setting its Custom Class to a WKInterfaceController subclass, launched the app in the simulator and navigated to the specified interface controller.

When I do so, I get the following error:

WatchKit error - unable to find interface controller class 'TestController' to instantiate

If I try to interact with the controller (e.g. try launching its button's action), I get the following error:

• *********** ERROR -[SPRemoteInterface _interfaceControllerClientIDForControllerID:] clientIdentifier for interfaceControllerID:(null) not found
• *********** ERROR -[SPRemoteInterface _interfaceControllerClientIDForControllerID:] clientIdentifier for interfaceControllerID:7120004 not found

I tried setting the module name as recommended on this answer, but that still gives me the following errors:

• WatchKit error - unable to find interface controller class '_TtC29myWatchApp_WatchKit_App19TestController' to instantiate
• *********** ERROR -[SPRemoteInterface _interfaceControllerClientIDForControllerID:] clientIdentifier for interfaceControllerID:(null) not found
• *********** ERROR -[SPRemoteInterface _interfaceControllerClientIDForControllerID:] clientIdentifier for interfaceControllerID:6E20004 not found

Answer 1

I got this error after renaming the WatchKit target, but finally realized: if you rename your WatchKit targets, you'll have to go through the interfaces in Interface Builder and make sure the module names for each of them is renamed as well.

You can do this by selecting an interface controller, clicking the Identity Inspector (or command-option-3), delete the module name, then tab away. It will automatically be filled in with the new target name. That did it for me!