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

Creating dynamic always-on wearable apps


An always-on app provides the user with the ability to view information at any time, without having to wake the device; however, the visible information may become stale if the actual information changes more frequently than once in a minute.

How to do it...

We may need to update the content on the wearable more frequently than once in a minute; thus, we can schedule an alarm to trigger an update outside the one-minute interval:

  1. We will need the wake lock permission on both, the handheld and wearable:

    [assembly: UsesPermission(Manifest.Permission.WakeLock)]
  2. If we want to support older wearables, we will need to set the wearable library as optional:

    [assembly: UsesLibrary(
      "com.google.android.wearable", false)]
  3. Next, we need to inherit it from WearableActivity:

    public class MainActivity : WearableActivity
  4. We are going to use the alarm manager to send us an Intent instance, which we will respond to by updating the UI. As the intent will try to launch a new...