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Android Programming for Beginners

You're reading from   Android Programming for Beginners Build in-depth, full-featured Android 9 Pie apps starting from zero programming experience

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Product type Paperback
Published in Oct 2018
Publisher Packt
ISBN-13 9781789538502
Length 766 pages
Edition 2nd Edition
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Author (1):
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John Horton John Horton
Author Profile Icon John Horton
John Horton
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Table of Contents (33) Chapters Close

Preface 1. Beginning Android and Java FREE CHAPTER 2. First Contact – Java, XML, and the UI Designer 3. Exploring Android Studio and the Project Structure 4. Getting Started with Layouts and Material Design 5. Beautiful Layouts with CardView and ScrollView 6. The Android Lifecycle 7. Java Variables, Operators, and Expressions 8. Java Decisions and Loops 9. Java Methods 10. Object-Oriented programming 11. More Object-Oriented Programming 12. The Stack, the Heap, and the Garbage Collector 13. Anonymous Classes – Bringing Android Widgets to Life 14. Android Dialog Windows 15. Arrays, ArrayList, Map and Random Numbers 16. Adapters and Recyclers 17. Data Persistence and Sharing 18. Localization 19. Animations and Interpolations 20. Drawing Graphics 21. Threads, and Starting the Live Drawing App 22. Particle Systems and Handling Screen Touches 23. Supporting Different Versions of Android, Sound Effects, and the Spinner Widget 24. Design Patterns, Multiple Layouts, and Fragments 25. Advanced UI with Paging and Swiping 26. Advanced UI with Navigation Drawer and Fragment 27. Android Databases 28. Coding a Snake Game Using Everything We Have Learned So Far 29. Enumerations and Finishing the Snake Game 30. A Quick Chat Before You Go Other Books You May Enjoy Index

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 SQLiteOpenHHelper. It will also define some final Strings to represent the names of the table and its columns. Furthermore, it will supply a bunch of helper methods we can call to perform all the necessary queries. Where necessary, these helper methods 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 methods should our app need to evolve:

Create a new class called DataManager and add the following member variables:

public class DataManager {

    // This is the actual database
    private SQLiteDatabase db;

    /*
        Next we have a public static final string...
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