First thing we will do is describe our database by defining its tables and columns with proper data types. We will also define simple models that will represent our data. To do so, create a new package called database:
com.journaler.database
Then, create a new Kotlin class called DbModel. The DbModel class will represent the matrix for all database models of our application and will contain only the ID, since the ID is a mandatory field and will be used as a primary key. Make sure your DbModel class looks like this:
package com.journaler.database
abstract class DbModel {
abstract var id: Long
} Now, when we define our starting point, we will define data classes that will actually contain data. Inside our existing package called model, create new classes--DbEntry, Note, and Todo. Note and Todo will extend Entry, which extends the DbModel class.
The Entry class code is as follows:
package com.journaler.model
import android.location...