Android Compose doesn't work with KSP, ROOM for multi-module projects

Question

I noticed after enabling Android Compose for the project:

buildFeatures {
  compose true
}

KSP with ROOM doesn't work properly finishing with exceptions like this during bulding project:

[ksp] [MissingType]: Element 'pl.softfly.multi_module_room.entity.Card' references a type that is not present - pl.softfly.multi_module_room.entity.Card

The problem occurs when the project is multi-module, ROOM from the module cannot to find ROOM classes from the parent project. If compose true is removed everything works as it should.

The project with Android Compose enabled (with exception): https://github.com/softfly/MultiModuleRoom/commit/de3f6bbd97cee282cf6f329c259dbcd6b6742666

The project with Android Compose disabled (works): https://github.com/softfly/MultiModuleRoom/commit/a5ce616bedfa438428b0ab1ce450e5eeee680474

Has anyone had a similar problem and was able to solve it?

Answer 1

I see a couple of issues:

You have the module dependencies backwards - the app module should have

implementation project(":roommodule")

and roommodule shouldn't reference the app module.

You should also place all of the room entities/daos/database declarations inside the roommodule. The app module should not have the room dependencies nor the KSP setup.

I didn't look closer into the code, but I fixing the above will give a clean separation between room/compose, and I suspect will fix at least this issue.