Book Image

Android High Performance Programming

By : Emil Atanasov, Enrique López Mañas, Diego Grancini
Book Image

Android High Performance Programming

By: Emil Atanasov, Enrique López Mañas, Diego Grancini

Overview of this book

Performant applications are one of the key drivers of success in the mobile world. Users may abandon an app if it runs slowly. Learning how to build applications that balance speed and performance with functionality and UX can be a challenge; however, it's now more important than ever to get that balance right. Android High Performance will start you thinking about how to wring the most from any hardware your app is installed on, so you can increase your reach and engagement. The book begins by providing an introduction to state–of-the-art Android techniques and the importance of performance in an Android application. Then, we will explain the Android SDK tools regularly used to debug and profile Android applications. We will also learn about some advanced topics such as building layouts, multithreading, networking, and security. Battery life is one of the biggest bottlenecks in applications; and this book will show typical examples of code that exhausts battery life, how to prevent this, and how to measure battery consumption from an application in every kind of situation to ensure your apps don’t drain more than they should. This book explains techniques for building optimized and efficient systems that do not drain the battery, cause memory leaks, or slow down with time.
Table of Contents (17 chapters)
Android High Performance Programming
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface
Index

Creating a native activity with Android NDK


In the following section, we are going to study how an application can be done entirely using native C code, without any Java code being required at all. Please note that this is done more for study purposes, as there are not many practical cases where developing a purely native application will be useful. However, it will serve as a good example of interaction between the different layers and the Android operational system.

Since we are not using Java code, we need to specify in the AndroidManifest.xml file that our project will contain no Java code. This is done using the following lines:

<application android:label="@string/app_name"
android:hasCode="false">

Applications using only native code are first supported from the API level 9 onwards. At the time of writing this book, this should not be a problem, since the versions comprising under API Level 9 ranked under 0.1% of the total. However, due to the nature of the NDK, you might be using...