Book Image

Xamarin Mobile Development for Android Cookbook

By : Matthew Leibowitz
Book Image

Xamarin Mobile Development for Android Cookbook

By: Matthew Leibowitz

Overview of this book

Xamarin is used by developers to write native iOS, Android, and Windows apps with native user interfaces and share code across multiple platforms not just on mobile devices, but on Windows, Mac OS X, and Linux. Developing apps with Xamarin.Android allows you to use and re-use your code and your skills on different platforms, making you more productive in any development. Although it’s not a write-once-run-anywhere framework, Xamarin provides native platform integration and optimizations. There is no middleware; Xamarin.Android talks directly to the system, taking your C# and F# code directly to the low levels. This book will provide you with the necessary knowledge and skills to be part of the mobile development era using C#. Covering a wide range of recipes such as creating a simple application and using device features effectively, it will be your companion to the complete application development cycle. Starting with installing the necessary tools, you will be guided on everything you need to develop an application ready to be deployed. You will learn the best practices for interacting with the device hardware, such as GPS, NFC, and Bluetooth. Furthermore, you will be able to manage multimedia resources such as photos and videos captured with the device camera, and so much more! By the end of this book, you will be able to create Android apps as a result of learning and implementing pro-level practices, techniques, and solutions. This book will ascertain a seamless and successful app building experience.
Table of Contents (20 chapters)
Xamarin Mobile Development for Android Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Shrinking the app package


No app uses all the features of all the included libraries. The .NET libraries are quite big, and we often only use a tiny subset. To reduce the size of an app, we need to remove any unnecessary code or libraries that exist in it.

How to do it...

To reduce the overall size of the app, we enable the linker. This is used to remove any unused code from our app, or from any assemblies that are used:

  1. We select either the Link SDK assemblies only option or the Link all assemblies option from the Linker behavior dropdown:

    The linker options

  2. When we link assemblies, types and members are removed. To prevent members from being removed, we can add the [Preserve] attribute to those members:

    public class MyClass {
      [Preserve]
      public string MyMember() {
      }
    }
  3. We can also request that the linker skip all the members on an entire type:

    [Preserve(AllMembers = true)]
    public class MyClass {
    }
  4. If we can't, or don't, want to use the [Preserve] attribute, we can provide a block of code that...