Coding the database class

Here, we will put into practice everything we have learned so far and finish coding the Age database app. Before our Fragment classes from the previous section can interact with a shared database, we need a class to handle interaction with, and creation of, the database.

We will create a class that manages our database by implementing SQLiteOpenHelper. It will also define some String variables in a companion object to represent the names of the table and its columns. Furthermore, it will supply a bunch of helper functions we can call to perform all the necessary queries. Where necessary, these helper functions will return a Cursor object that we can use to show the data we have retrieved. It would be trivial then to add new helper functions should our app need to evolve:

Create a new class called DataManager and add the companion object, the constructor, and the init block:

Tip

We discussed the companion object in Chapter 25, Advanced UI with Paging and Swiping

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