Warning using room database: schema export directory is not provided to the annotation processor so we cannot export

Warning : Schema export directory is not provided to the annotation processor so we cannot export the schema. You can either provide `room.schemaLocation` annotation processor argument OR set exportSchema to false.
public abstract class MyRoomDatabase extends RoomDatabase {

Not provided to annotation processor framework Export directory , Therefore, the schema cannot be exported . You can provide room.schemaLocation Annotate processor parameters or exportSchema Set to false

resolvent

1、 stay build gradle Add （ recommend ）

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

2.exportSchema = false