Expected @HiltAndroidApp to have a value. Did you forget to apply the Gradle Plugin?

I just hit this problem this morning. Do you have anything in your build.gradle that adds arguments to the annotationProcessOptions? For example:

  android {
        ...
        defaultConfig {
            ...
            javaCompileOptions {
                annotationProcessorOptions {
                    arguments = ["room.schemaLocation":
                                 "$projectDir/schemas".toString()]
                }
            }
        }
    }

If so, try changing from “arguments =” to “arguments +=”, as just using equals overwrites anything set previously.