Book Image

Android Programming for Beginners

By : John Horton, Paresh Mayani
Book Image

Android Programming for Beginners

By: John Horton, Paresh Mayani

Overview of this book

Android is the most popular OS in the world. There are millions of devices accessing tens of thousands of applications. It is many people's entry point into the world of technology; it is an operating system for everyone. Despite this, the entry-fee to actually make Android applications is usually a computer science degree, or five years’ worth of Java experience. Android Programming for Beginners will be your companion to create Android applications from scratch—whether you’re looking to start your programming career, make an application for work, be reintroduced to mobile development, or are just looking to program for fun. We will introduce you to all the fundamental concepts of programming in an Android context, from the Java basics to working with the Android API. All examples are created from within Android Studio, the official Android development environment that helps supercharge your application development process. After this crash-course, we’ll dive deeper into Android programming and you’ll learn how to create applications with a professional-standard UI through fragments, make location-aware apps with Google Maps integration, and store your user’s data with SQLite. In addition, you’ll see how to make your apps multilingual, capture images from a device’s camera, and work with graphics, sound, and animations too. By the end of this book, you’ll be ready to start building your own custom applications in Android and Java.
Table of Contents (37 chapters)
Android Programming for Beginners
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Coding the communications interface


We know that TitlesFragment needs a way to communicate with ViewFragment, but also TagsFragment needs a way of telling TitlesFragment which tag it would like to use for the criteria to search for database entries with the matching tag.

This same interface will handle all this work. MainActivity can then implement the interface and handle the inter-fragment communication.

Create a new class called ActivityComs and code it into our interface by editing it to exactly the code shown next:

public interface ActivityComs {

  void onTitlesListItemSelected(int pos);

  void onTagsListItemSelected(String tag);
} 

We now have two methods we can use for communicating between our Fragment classes and MainActivity. One (onTitlesListItemSelected) will pass in an int to represent the _id of the row in our database of the required Photo object. The other (onTagsListItemSelected) will pass a string that is the tag to be searched for and matched against rows in the wis_table_photos...