A crazy problem is that after the project is transferred to kotlin, it always reports: unresolved reference: XXXXXXX
the pre compilation of the project can report no error, but the problem is reported as soon as the mark is marked. The location of the problem is related to the interface defined by kotlin in in the project,
so it begins to solve:
check whether there are bugs in the definition code of the interface. The conclusion is no problem. Check whether there are bugs in the implementation of the interface. The conclusion is that the implementation class has not been executed to the environment, whether there are problems, and the version of gradle and other related tools has not been upgraded. Therefore, create a new kotlin module to import the error interface class, Results it works normally

conclusion:
when defining the interface of kotlin in the module of Java environment, an error will be reported during compilation.