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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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Toc

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

Exploring the project's Java code and the main layout's XML code

We are going to look at the resource files that have the code that defines our simple UI layout and the file that has our Java code. At this stage, we will not try to understand it all as we need to learn some more basics before it makes sense to do so. What we will see, however, is the basic content and structure of both files so we can reconcile their content with what we already know about Android resources and Java.

Examining the HelloWorldActivity.java file

Let's look at the Java code first. You can see this code by left-clicking on the HelloWorldActivity.java tab, as shown in the following screenshot:

Examining the HelloWorldActivity.java file

As we are not looking at the intricate details of the code, an annotated screenshot is more useful than reproducing the actual code in text form. Regularly refer to the following screenshot while reading on with this section:

Examining the HelloWorldActivity.java file

The first thing to note is that I have added a few empty lines amongst the code to space...

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