Book Image

Android Things Projects

By : Francesco Azzola
Book Image

Android Things Projects

By: Francesco Azzola

Overview of this book

Android Things makes developing connected embedded devices easy by providing the same Android development tools, best-in-class Android framework, and Google APIs that make developers successful on mobile. With this book, you will be able to take advantage of the new Android framework APIs to securely build projects using low-level components such as sensors, resistors, capacitors, and display controllers. This book will teach you all you need to know about working with Android Things through practical projects based on home automation, robotics, IoT, and so on. We’ll teach you to make the most of the Android Things and build enticing projects such as a smart greenhouse that controls the climate and environment automatically. You’ll also create an alarm system, integrate Android Things with IoT cloud platforms, and more. By the end of this book, you will know everything about Android Things, and you’ll have built some very cool projects using the latest technology that is driving the adoption of IoT. You will also have primed your mindset so that you can use your knowledge for profitable, practical projects.
Table of Contents (15 chapters)
Title Page
About the Author
About the Reviewers
Customer Feedback

How to close the connection with a GPIO pin

In this last step, we will learn how to close the connection with a GPIO pin. This is an important step because in this way, we free the resources and remove all the listeners we added to the GPIO pins.

An Android Things app has a life cycle very similar to an Android app. The place where we implement these actions is the Activity onDestroy method. In this method we have to:

  • Remove all the listeners attached to the GPIO pins
  • Close the connection to the GPIO pins

So, open again and look for the onDestroy method and modify it:

protected void onDestroy()
  { super.onDestroy(); Log.d(TAG, "onDestroy");
  if (gpioPin != null) {
      try {
    gpioPin.close(); gpioPin = null;
    catch(Exception e) {}