Search icon Close icon
Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
Checkout

Change country

Modal Close icon
Country selected Country selected
country flag United States
Country selected
country flag Great Britain
Country selected
country flag India
Country selected
country flag Germany
Country selected
country flag France
Country selected
country flag Canada
Country selected
country flag Russia
Country selected
country flag Spain
Country selected
country flag Brazil
Country selected
country flag Australia
Country selected
country flag Singapore
Country selected
country flag Hungary
Country selected
country flag Ukraine
Country selected
country flag Luxembourg
Country selected
country flag Estonia
Country selected
country flag Lithuania
Country selected
country flag South Korea
Country selected
country flag Turkey
Country selected
country flag Switzerland
Country selected
country flag Colombia
Country selected
country flag Taiwan
Country selected
country flag Chile
Country selected
country flag Norway
Country selected
country flag Ecuador
Country selected
country flag Indonesia
Country selected
country flag New Zealand
Country selected
country flag Cyprus
Country selected
country flag Denmark
Country selected
country flag Finland
Country selected
country flag Poland
Country selected
country flag Malta
Country selected
country flag Czechia
Country selected
country flag Austria
Country selected
country flag Sweden
Country selected
country flag Italy
Country selected
country flag Egypt
Country selected
country flag Belgium
Country selected
country flag Portugal
Country selected
country flag Slovenia
Country selected
country flag Ireland
Country selected
country flag Romania
Country selected
country flag Greece
Country selected
country flag Argentina
Country selected
country flag Netherlands
Country selected
country flag Bulgaria
Country selected
country flag Latvia
Country selected
country flag South Africa
Country selected
country flag Malaysia
Country selected
country flag Japan
Country selected
country flag Slovakia
Country selected
country flag Philippines
Country selected
country flag Mexico
Country selected
country flag Thailand
Country selected
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Newsletter Hub
Free Learning
Arrow right icon
timer SALE ENDS IN
0 Days
:
00 Hours
:
00 Minutes
:
00 Seconds
Home > Mobile > Android Development > Asynchronous Android
Asynchronous Android
Asynchronous Android

Asynchronous Android: As an Android developer you know you're in a competitive marketplace. This book can give you the edge by guiding you through the concurrency constructs and proper use of AsyncTask to create smooth user interfaces.

Arrow left icon
Profile Icon Steve Liles
Arrow right icon
$43.99
Full star icon Full star icon Full star icon Full star icon Half star icon 4.8 (4 Ratings)
Paperback Dec 2013 146 pages 1st Edition
eBook
$22.99 $25.99
Paperback
$43.99
Subscription
Free Trial
Renews at $19.99p/m
Arrow left icon
Profile Icon Steve Liles
Arrow right icon
$43.99
Full star icon Full star icon Full star icon Full star icon Half star icon 4.8 (4 Ratings)
Paperback Dec 2013 146 pages 1st Edition
eBook
$22.99 $25.99
Paperback
$43.99
Subscription
Free Trial
Renews at $19.99p/m
eBook
$22.99 $25.99
Paperback
$43.99
Subscription
Free Trial
Renews at $19.99p/m

What do you get with Print?

Product feature icon Instant access to your digital copy whilst your Print order is Shipped
Product feature icon Paperback book shipped to your preferred address
Product feature icon Redeem a companion digital copy on all Print orders
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
OR

Contact Details

Modal Close icon
Payment Processing...
tick Completed

Shipping Address

Billing Address

Shipping Methods
Table of content icon View table of contents Preview book icon Preview Book

Asynchronous Android

Chapter 2. Staying Responsive with AsyncTask

The first Android-specific concurrency construct we'll look at is android.os.AsyncTask, a neat construct that encapsulates the messy business of managing threads, performing background work, and publishing progress and results back to the main thread to update the user interface.

In this chapter we will cover the following topics:

  • Introducing AsyncTask

  • Declaring AsyncTask types

  • Executing AsyncTasks

  • Providing feedback to the user

  • Providing progress updates

  • Canceling AsyncTasks

  • Handling exceptions

  • Controlling the level of concurrency

  • Common AsyncTask issues

  • Applications of AsyncTask

Introducing AsyncTask

AsyncTask was introduced in Android at API level 3, Cupcake, with the express purpose of helping developers to avoid blocking the main thread. The Async part of the name of this class comes from the word asynchronous, which literally means not occurring at the same time.

AsyncTask is an abstract class, and as such, must be subclassed for use. At the minimum, our subclass must provide an implementation for the abstract doInBackground method, which defines the work that we want to get done off the main thread.

protected Result doInBackground(Params… params)

There are four other methods of AsyncTask which we may choose to override:

protected void onPreExecute()
protected void onProgressUpdate(Progress… values)
protected void onPostExecute(Result result)
protected void onCancelled(Result result)

Although we will override one or more of these five methods, we will not invoke them directly from our own code. These are callback methods, meaning that they will be invoked for us...

Declaring AsyncTask types

AsyncTask is a generically typed class, and exposes three type parameters:

abstract class AsyncTask<Params, Progress, Result>

When we declare an AsyncTask subclass, we'll specify types for Params, Progress, and Result; for example, if we want to pass a String parameter to doInBackground, report progress as a Float, and return a Boolean result, we would declare our AsyncTask subclass as follows:

public class MyTask extends AsyncTask<String, Float, Boolean>

If we don't need to pass any parameters, or don't want to report progress, a good type to use for those parameters is java.lang.Void, which signals our intent clearly, because Void is an uninstantiable class representing the void keyword.

Let's take a look at a first example, performing an expensive calculation in the background and reporting the result to the main thread:

public class PrimesTask
extends AsyncTask<Integer, Void, BigInteger> {
  private TextView resultView;

  public PrimesTask(TextView...

Executing AsyncTasks

Having implemented doInBackground and onPostExecute, we want to get our task running. There are two methods we can use for this, each offering different levels of control over the degree of concurrency with which our tasks are executed. Let's look at the simpler of the two methods first:

public final AsyncTask<Params, Progress, Result> execute(Params… params)

The return type is the type of our AsyncTask subclass, which is simply for convenience so that we can use method chaining to instantiate and start a task in a single line and still record a reference to the instance:

class MyTask implements AsyncTask<String,Void,String>{ … }
MyTask task = new MyTask().execute("hello");

The Params… params argument is the same Params type we used in our class declaration, because the values we supply to the execute method are later passed to our doInBackground method as its Params… params arguments. Notice that it is a varargs parameter, meaning that we can pass any number...

Providing feedback to the user

Having started what we know to be a potentially long-running task, we probably want to let the user know that something is happening. There are a lot of ways of doing this, but a common approach is to present a dialog displaying a relevant message.

A good place to present our dialog is from the onPreExecute method of AsyncTask, which executes on the main thread. Hence, it is allowed to interact with the user interface.

The modified PrimesTask will need a reference to a Context, so that it can prepare a ProgressDialog, which it will show and dismiss in onPreExecute and onPostExecute respectively. As doInBackground has not changed, it is not shown in the following code, for brevity:

public class PrimesTask extends AsyncTask<Integer, Void, BigInteger>{
  private Context ctx;
  private ProgressDialog progress;
  private TextView resultView;

  public PrimesTask(Context ctx, TextView resultView) {
    this.ctx = ctx;
      this.resultView = resultView;
  }

...

Canceling AsyncTask

Another nice usability touch we can provide for our users is the ability to cancel a task before it completes—for example, if the task depends on some user input and, after starting the execution, the user realizes that they have provided the wrong value. AsyncTask provides support for cancellation with the cancel method.

public final boolean cancel(boolean mayInterruptIfRunning)

The mayInterruptIfRunning parameter allows us to specify whether an AsyncTask thread that is in an interruptible state may actually be interrupted—for example, if our doInBackground code is performing interruptible I/O.

Simply invoking cancel is not sufficient to cause our task to finish early. We need to actively support cancellation by periodically checking the value returned from isCancelled and reacting appropriately in doInBackground.

First, let's set up our ProgressDialog to trigger the AsyncTask's cancel method by adding a few lines to onPreExecute:

progress.setCancelable(true);
progress.setOnCancelListener...

Handling exceptions

The callback methods defined by AsyncTask dictate that we cannot throw checked exceptions, so we must wrap any code that throws checked exceptions with try/catch blocks. Unchecked exceptions that propagate out of AsyncTask's methods will crash our application, so we must test carefully and handle these if necessary.

For the callback methods that run on the main thread—onPreExecute, onProgressUpdate, onPostExecute, and onCancelled—we can catch exceptions in the method and directly update the user interface to alert the user.

Of course, exceptions are likely to arise in our doInBackground method too, as this is where the bulk of the work of AsyncTask is done, but unfortunately, we can't update the user interface from doInBackground. A simple solution is to have doInBackground return an object that may contain either the result or an exception, as follows:

static class Result<T> {
  private T actual;
  private Exception exc;
}
@Override
protected final Result<T&gt...

Controlling the level of concurrency

So far, we've carefully avoided being too specific about what exactly happens when we invoke AsyncTask's execute method. We know that doInBackground will execute off the main thread, but what exactly does that mean?

The original goal of AsyncTask was to help developers avoid blocking the main thread. In its initial form at API level 3, AsyncTasks were queued and executed serially (that is, one after the other) on a single background thread, guaranteeing that they would complete in the order they were started.

This changed in API level 4 to use a pool of up to 128 threads to execute multiple AsyncTasks concurrently with each other—a level of concurrency of up to 128. At first glance, this seems like a good thing, since a common use case for AsyncTask is to perform blocking I/O, where the thread spends much of its time idly waiting for data.

However, as we saw in Chapter 1, Building Responsive Android Applications, there are many issues that commonly arise...

Common AsyncTask issues

As with any powerful programming abstraction, AsyncTask is not entirely free from issues and compromises.

Fragmentation issues

In the Controlling the level of concurrency section, we saw how AsyncTask has evolved with new releases of the Android platform, resulting in behavior that varies with the platform of the device running the task, which is a part of the wider issue of fragmentation.

The simple fact is that if we target a broad range of API levels, the execution characteristics of our AsyncTasks—and therefore, the behavior of our apps—can vary considerably on different devices. So what can we do to reduce the likelihood of encountering AsyncTask issues due to fragmentation?

The most obvious approach is to deliberately target devices running at least Honeycomb, by setting a minSdkVersion of 11 in the Android Manifest file. This neatly puts us in the category of devices, which, by default, execute AsyncTasks serially, and therefore, much more predictably.

However,...

Applications of AsyncTask

Now that we have seen how to use AsyncTask, we might ask ourselves when we should use it.

Good candidate applications for AsyncTask tend to be relatively short-lived operations (at most, for a second or two), which pertain directly to a specific Fragment or Activity and need to update its user interface.

AsyncTask is ideal for running short, CPU-intensive tasks, such as number crunching or searching for words in large text strings, moving them off the main thread so that it can remain responsive to input and maintain high frame rates.

Blocking I/O operations such as reading and writing text files, or loading images from local files with BitmapFactory, are also good use cases for AsyncTask.

Of course, there are use cases for which AsyncTask is not ideally suited. For anything that requires more than a second or two, we should weigh the cost of performing this operation repeatedly if the user rotates the device, or switches between apps or activities, or whatever else...

Summary

In this chapter, we've taken a detailed look at AsyncTask and how to use it to write responsive applications that perform operations without blocking the main thread.

We saw how to keep the user informed of the progress, and even allow them to cancel operations early. We also learned how to deal with issues that can arise when the Activity lifecycle conspires against our background tasks.

Finally, we considered when to use AsyncTask, and when it might not be appropriate.

In the next chapter, we'll take a look at some lower-level constructs—fundamental building blocks on which the other concurrency mechanisms of the platform, including AsyncTask, are built.

Left arrow icon

Page 1 of 11

Right arrow icon

Key benefits

  • Learn how to use Android's high-level concurrency constructs to keep your applications smooth and responsive
  • Leverage the full power of multi-core mobile CPUs to get more work done in less time
  • From quick calculations to scheduled downloads, each chapter explains the available mechanisms of asynchronous programming in detail

Description

With more than a million apps available from Google Play, it is more important than ever to build apps that stand out from the crowd. To be successful, apps must react quickly to user input, deliver results in a flash, and sync data in the background. The key to this is understanding the right way to implement asynchronous operations that work with the platform, instead of against it. Asynchronous Android is a practical book that guides you through the concurrency constructs provided by the Android platform, illustrating the applications, benefits, and pitfalls of each.Learn to use AsyncTask correctly to perform operations in the background, keeping user-interfaces running smoothly while avoiding treacherous memory leaks. Discover Handler, HandlerThread and Looper, the related and fundamental building blocks of asynchronous programming in Android. Escape from the constraints of the Activity lifecycle to load and cache data efficiently across your entire application with the Loader framework. Keep your data fresh with scheduled tasks, and understand how Services let your application continue to run in the background, even when the user is busy with something else.Asynchronous Android will help you to build well-behaved apps with smooth, responsive user-interfaces that delight users with speedy results and data that's always fresh, and keep the system happy and the battery charged by playing by the rules.

Who is this book for?

This book is for Android developers who want to learn about the advanced concepts of Android programming. No prior knowledge of concurrency and asynchronous programming is required. This book is also targeted towards Java experts who are new to Android.

What you will learn

  • Understand Android s process model and its implications on your applications
  • Exercise multithreading to build well-behaved Android applications that work with the platform
  • Apply and control concurrency to deliver results quickly and keep your applications responsive to user input
  • Discover Android-specific constructs that make asynchronous programming easy and efficient
  • Learn how to apply Android s concurrency constructs to build smooth and responsive applications
Estimated delivery fee Deliver to South Africa

Standard delivery 10 - 13 business days

$12.95

Premium delivery 3 - 6 business days

$34.95
(Includes tracking information)

Product Details

Country selected
Publication date, Length, Edition, Language, ISBN-13
Publication date : Dec 24, 2013
Length: 146 pages
Edition : 1st
Language : English
ISBN-13 : 9781783286874
Category :
Mobile
Languages :
Java
Concepts :
Android Development
Tools :
Android

What do you get with Print?

Product feature icon Instant access to your digital copy whilst your Print order is Shipped
Product feature icon Paperback book shipped to your preferred address
Product feature icon Redeem a companion digital copy on all Print orders
Product feature icon Access this title in our online reader with advanced features
Product feature icon DRM FREE - Read whenever, wherever and however you want
OR

Contact Details

Modal Close icon
Payment Processing...
tick Completed

Shipping Address

Billing Address

Shipping Methods
Estimated delivery fee Deliver to South Africa

Standard delivery 10 - 13 business days

$12.95

Premium delivery 3 - 6 business days

$34.95
(Includes tracking information)

Product Details

Publication date : Dec 24, 2013
Length: 146 pages
Edition : 1st
Language : English
ISBN-13 : 9781783286874
Category :
Mobile
Languages :
Java
Concepts :
Android Development
Tools :
Android

Packt Subscriptions

See our plans and pricing
Modal Close icon
$19.99 billed monthly
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Simple pricing, no contract
START FREE TRIAL
BUY NOW
$199.99 billed annually
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts
START FREE TRIAL
BUY NOW
$279.99 billed in 18 months
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts
START FREE TRIAL
BUY NOW

Frequently bought together

Android Application Security Essentials
Android Application Security Essentials
Read more
Aug 2013 218 pages
Full star icon 4 (2)
eBook
eBook
  • eBook eBook $25.99
  • Paperback Paperback $48.99
$25.99 $28.99
$48.99
Asynchronous Android
Asynchronous Android
Read more
Dec 2013 146 pages
Full star icon 4.8 (4)
eBook
eBook
  • eBook eBook $22.99
  • Paperback Paperback $43.99
$22.99 $25.99
$43.99
Creating Dynamic UI with Android Fragments
Creating Dynamic UI with Android Fragments
Read more
Sep 2013 122 pages
Full star icon 4.1 (10)
eBook
eBook
  • eBook eBook $22.99
  • Paperback Paperback $43.99
$22.99 $25.99
$43.99
Stars icon
Total $ 136.97
Android Application Security Essentials
$48.99
Asynchronous Android
$43.99
Creating Dynamic UI with Android Fragments
$43.99
Total $ 136.97 Stars icon

Table of Contents

7 Chapters
Building Responsive Android Applications Chevron down icon Chevron up icon
Building Responsive Android Applications
Introducing the Dalvik Virtual Machine
Understanding the Android thread model
Summary
Staying Responsive with AsyncTask Chevron down icon Chevron up icon
Staying Responsive with AsyncTask
Introducing AsyncTask
Declaring AsyncTask types
Executing AsyncTasks
Providing feedback to the user
Canceling AsyncTask
Handling exceptions
Controlling the level of concurrency
Common AsyncTask issues
Applications of AsyncTask
Summary
Distributing Work with Handler and HandlerThread Chevron down icon Chevron up icon
Distributing Work with Handler and HandlerThread
Understanding Looper
Building responsive apps with Handler
Handler programming issues
Applications of Handler and HandlerThread
Summary
Asynchronous I/O with Loader Chevron down icon Chevron up icon
Asynchronous I/O with Loader
Introducing Loaders
Building responsive apps with AsyncTaskLoader
Building responsive apps with CursorLoader
Combining Loaders
Applications of Loaders
Summary
Queuing Work with IntentService Chevron down icon Chevron up icon
Queuing Work with IntentService
Introducing Service and IntentService
Building responsive apps with IntentService
Applications of IntentService
Summary
Long-running Tasks with Service Chevron down icon Chevron up icon
Long-running Tasks with Service
Building responsive apps with Service
Communicating with Services
Applications of Services
Summary
Scheduling Work with AlarmManager Chevron down icon Chevron up icon
Scheduling Work with AlarmManager
Scheduling alarms with AlarmManager
Handling alarms
Staying awake with WakeLocks
Applications of AlarmManager
Summary

Recommendations for you

Left arrow icon
.NET MAUI Cookbook
.NET MAUI Cookbook
Read more
Dec 2024 384 pages
Full star icon 4.3 (3)
eBook
eBook
  • eBook eBook $31.99
  • Paperback Paperback $44.99
$31.99 $35.99
$44.99
iOS 18 Programming for Beginners
iOS 18 Programming for Beginners
Read more
Dec 2024 584 pages
Full star icon 4.4 (7)
eBook
eBook
  • eBook eBook $31.99
  • Paperback Paperback $44.99
$31.99 $35.99
$44.99
Apps and Services with .NET 8
Apps and Services with .NET 8
Read more
Dec 2023 798 pages
Full star icon 4.8 (23)
eBook
eBook
  • eBook eBook $35.98
  • Paperback Paperback $49.99
$35.98 $39.99
$49.99
Flutter Design Patterns and Best Practices
Flutter Design Patterns and Best Practices
Read more
Sep 2024 362 pages
Full star icon 4.2 (5)
eBook
eBook
  • eBook eBook $31.99
  • Paperback Paperback $44.99
$31.99 $35.99
$44.99
Mastering iOS 18 Development
Mastering iOS 18 Development
Read more
Nov 2024 418 pages
Full star icon 5 (2)
eBook
eBook
  • eBook eBook $29.99
  • Paperback Paperback $41.99
$29.99 $33.99
$41.99
Mastering Kotlin for Android 14
Mastering Kotlin for Android 14
Read more
Apr 2024 370 pages
Full star icon 5 (9)
eBook
eBook
  • eBook eBook $27.99
  • Paperback Paperback $39.99
$27.99 $31.99
$39.99
Thriving in Android Development Using Kotlin
Thriving in Android Development Using Kotlin
Read more
Jul 2024 410 pages
Full star icon 4.5 (6)
eBook
eBook
  • eBook eBook $38.99
  • Paperback Paperback $54.99
$38.99 $43.99
$54.99
Swift Cookbook
Swift Cookbook
Read more
Jun 2024 422 pages
Full star icon 5 (3)
eBook
eBook
  • eBook eBook $27.99
  • Paperback Paperback $39.99
$27.99 $31.99
$39.99
Android Programming for Beginners
Android Programming for Beginners
Read more
Apr 2021 742 pages
Full star icon 4.2 (12)
eBook
eBook
  • eBook eBook $31.99
  • Paperback Paperback $43.99
$31.99 $35.99
$43.99
How to Build Android Apps with Kotlin
How to Build Android Apps with Kotlin
Read more
May 2023 704 pages
Full star icon 4.4 (14)
eBook
eBook
  • eBook eBook $74.99
  • Paperback Paperback $103.99
$74.99 $83.99
$103.99
Right arrow icon

Customer reviews

Rating distribution
Full star icon Full star icon Full star icon Full star icon Half star icon 4.8
(4 Ratings)
5 star 75%
4 star 25%
3 star 0%
2 star 0%
1 star 0%
Brett Sep 28, 2014
Full star icon Full star icon Full star icon Full star icon Full star icon 5
This is the best book to learn about the android framework's async features. There are other broader books on android that will give a chapter or two to the various pieces of the framework that are provided to help you run tasks asynchronously but they always seem to leave you wanting and wandering Google for a little more information. The author gives a thorough introduction to each of the tools provided by android to help its developers run tasks in parallel.I would recommend reading the entire book but it is organized nicely and each component gets its own chapter. If you are simply dealing with asynctasks and life cycle issues related to asynctasks you can open this book to that chapter and be happily on your way.Overall because of the importance that android places on not blocking an application's main thread means that every android developer should read this book to get the best performance and stability from their apps.
Amazon Verified review Amazon
Philip Arad Apr 07, 2014
Full star icon Full star icon Full star icon Full star icon Full star icon 5
With more than a million apps available from Google Play, Android has quickly become one of the most popular mobile operating system in use. Nowadays it is more important than ever to build apps that react quickly to user input, deliver results in a flash, and sync data in the background. Among the many things that contribute to a great user experience, responsiveness is the most important. Before making your app available to your users you must eliminate pauses and glitches while scrolling content, remove user interfaces that freeze while loading data from storage, add progress updates to let us know what's happening, and so on. In order to accomplish this task you must understand how to implement asynchronous operations that work with the Android platformTo address this problem efficiently, I recommend reading the book 'Asynchronous Android' from 'Packt Publishing' (see [...] )'Asynchronous Android' is a practical book that guides you through the concurrency constructs provided by the Android platform, illustrating the applications, benefits, and pitfalls of each.Reading the book, you will learn to use AsyncTask correctly to perform operations in the background, keeping user-interfaces running smoothly while avoiding treacherous memory leaks. Discover Handler, HandlerThread and Looper, the related and fundamental building blocks of asynchronous programming in Android. Escape from the constraints of the Activity lifecycle to load and cache data efficiently across your entire application with the Loader framework. Keep your data fresh with scheduled tasks, and understand how Services let your application continue to run in the background, even when the user is busy with something else.Asynchronous Android will help you to build well-behaved apps with smooth, responsive user-interfaces that delight users with speedy results and data that’s always fresh, and keep the system happy and the battery charged by playing by the rules.
Amazon Verified review Amazon
Liang Ma Sep 14, 2014
Full star icon Full star icon Full star icon Full star icon Full star icon 5
Very concise, but informative and helpful. Well worth the money. Sincerely recommend this great book to all Android developers.
Amazon Verified review Amazon
R. Williams Mar 24, 2014
Full star icon Full star icon Full star icon Full star icon Empty star icon 4
Give this book a little bit of credit for doing a decent job of covering the waterfront which is kind of vast. You can figure most of the same things out reading the documentation, but this is a good single source, for example, to figure out if you want to use Handlers or AsyncTasks, etc. Frankly, this is one of the best things books can provide when their topic is as wide ranging as an operating system, and the Android docs do not do this very well. The section on Services is really pretty good: there is discussion of IntentService vs. extending Service itself, and the rationale for doing services (which is actually quite broad).The negatives in this book is that the material is pretty thin. For instance, there is no in depth discussion of things like the looper. There is no discussion at all about testing. It all kind of has the feel of just 'if you're looking for x, go to door y.' Also, there are a few sections of the book that are completely absurd like the one where the author uses a file download as an example of something that ought be implemented as a service, then in the chapter summary he calls it the best example of a service. On earth? Huh??Just barely made 4 and that's because of the success in providing comparative summaries that the documentation lacks.
Amazon Verified review Amazon

People who bought this also bought

Left arrow icon
Apps and Services with .NET 7
Apps and Services with .NET 7
Read more
Nov 2022 814 pages
Full star icon 4.8 (27)
eBook
eBook
  • eBook eBook $35.98
  • Paperback Paperback $49.99
$35.98 $39.99
$49.99
Apps and Services with .NET 8
Apps and Services with .NET 8
Read more
Dec 2023 798 pages
Full star icon 4.8 (23)
eBook
eBook
  • eBook eBook $35.98
  • Paperback Paperback $49.99
$35.98 $39.99
$49.99
Machine Learning Techniques for Text
Machine Learning Techniques for Text
Read more
Oct 2022 448 pages
Full star icon 4.8 (6)
eBook
eBook
  • eBook eBook $33.99
  • Paperback Paperback $46.99
$33.99 $37.99
$46.99
iOS 16 Programming for Beginners
iOS 16 Programming for Beginners
Read more
Nov 2022 686 pages
Full star icon 4.7 (50)
eBook
eBook
  • eBook eBook $31.99
  • Paperback Paperback $44.99
$31.99 $35.99
$44.99
Test-Driven iOS Development with Swift
Test-Driven iOS Development with Swift
Read more
Apr 2022 280 pages
Full star icon 5 (3)
eBook
eBook
  • eBook eBook $23.99
  • Paperback Paperback $33.99
$23.99 $26.99
$33.99
Right arrow icon

About the author

Profile icon Steve Liles
Steve Liles
Steve Liles is a self-confessed geek and has been an Android fan since the launch day of the G1. When he isn't at work building publishing systems and apps for newspapers and magazines, you'll find him tinkering with his own apps, building 3D printers, or playing RTS games. He is currently working with a start-up to build an advertising system that links the print and digital worlds using computer vision on Android and iOS devices.
Read more
See other products by Steve Liles
Get free access to Packt library with over 7500+ books and video courses for 7 days!
Start Free Trial

FAQs

What is the digital copy I get with my Print order? Chevron down icon Chevron up icon

When you buy any Print edition of our Books, you can redeem (for free) the eBook edition of the Print Book you’ve purchased. This gives you instant access to your book when you make an order via PDF, EPUB or our online Reader experience.

What is the delivery time and cost of print book? Chevron down icon Chevron up icon

Shipping Details

USA:

'

Economy: Delivery to most addresses in the US within 10-15 business days

Premium: Trackable Delivery to most addresses in the US within 3-8 business days

UK:

Economy: Delivery to most addresses in the U.K. within 7-9 business days.
Shipments are not trackable

Premium: Trackable delivery to most addresses in the U.K. within 3-4 business days!
Add one extra business day for deliveries to Northern Ireland and Scottish Highlands and islands

EU:

Premium: Trackable delivery to most EU destinations within 4-9 business days.

Australia:

Economy: Can deliver to P. O. Boxes and private residences.
Trackable service with delivery to addresses in Australia only.
Delivery time ranges from 7-9 business days for VIC and 8-10 business days for Interstate metro
Delivery time is up to 15 business days for remote areas of WA, NT & QLD.

Premium: Delivery to addresses in Australia only
Trackable delivery to most P. O. Boxes and private residences in Australia within 4-5 days based on the distance to a destination following dispatch.

India:

Premium: Delivery to most Indian addresses within 5-6 business days

Rest of the World:

Premium: Countries in the American continent: Trackable delivery to most countries within 4-7 business days

Asia:

Premium: Delivery to most Asian addresses within 5-9 business days

Disclaimer:
All orders received before 5 PM U.K time would start printing from the next business day. So the estimated delivery times start from the next day as well. Orders received after 5 PM U.K time (in our internal systems) on a business day or anytime on the weekend will begin printing the second to next business day. For example, an order placed at 11 AM today will begin printing tomorrow, whereas an order placed at 9 PM tonight will begin printing the day after tomorrow.


Unfortunately, due to several restrictions, we are unable to ship to the following countries:

  1. Afghanistan
  2. American Samoa
  3. Belarus
  4. Brunei Darussalam
  5. Central African Republic
  6. The Democratic Republic of Congo
  7. Eritrea
  8. Guinea-bissau
  9. Iran
  10. Lebanon
  11. Libiya Arab Jamahriya
  12. Somalia
  13. Sudan
  14. Russian Federation
  15. Syrian Arab Republic
  16. Ukraine
  17. Venezuela
What is custom duty/charge? Chevron down icon Chevron up icon

Customs duty are charges levied on goods when they cross international borders. It is a tax that is imposed on imported goods. These duties are charged by special authorities and bodies created by local governments and are meant to protect local industries, economies, and businesses.

Do I have to pay customs charges for the print book order? Chevron down icon Chevron up icon

The orders shipped to the countries that are listed under EU27 will not bear custom charges. They are paid by Packt as part of the order.

List of EU27 countries: www.gov.uk/eu-eea:

A custom duty or localized taxes may be applicable on the shipment and would be charged by the recipient country outside of the EU27 which should be paid by the customer and these duties are not included in the shipping charges been charged on the order.

How do I know my custom duty charges? Chevron down icon Chevron up icon

The amount of duty payable varies greatly depending on the imported goods, the country of origin and several other factors like the total invoice amount or dimensions like weight, and other such criteria applicable in your country.

For example:

  • If you live in Mexico, and the declared value of your ordered items is over $ 50, for you to receive a package, you will have to pay additional import tax of 19% which will be $ 9.50 to the courier service.
  • Whereas if you live in Turkey, and the declared value of your ordered items is over € 22, for you to receive a package, you will have to pay additional import tax of 18% which will be € 3.96 to the courier service.
How can I cancel my order? Chevron down icon Chevron up icon

Cancellation Policy for Published Printed Books:

You can cancel any order within 1 hour of placing the order. Simply contact customercare@packt.com with your order details or payment transaction id. If your order has already started the shipment process, we will do our best to stop it. However, if it is already on the way to you then when you receive it, you can contact us at customercare@packt.com using the returns and refund process.

Please understand that Packt Publishing cannot provide refunds or cancel any order except for the cases described in our Return Policy (i.e. Packt Publishing agrees to replace your printed book because it arrives damaged or material defect in book), Packt Publishing will not accept returns.

What is your returns and refunds policy? Chevron down icon Chevron up icon

Return Policy:

We want you to be happy with your purchase from Packtpub.com. We will not hassle you with returning print books to us. If the print book you receive from us is incorrect, damaged, doesn't work or is unacceptably late, please contact Customer Relations Team on customercare@packt.com with the order number and issue details as explained below:

  1. If you ordered (eBook, Video or Print Book) incorrectly or accidentally, please contact Customer Relations Team on customercare@packt.com within one hour of placing the order and we will replace/refund you the item cost.
  2. Sadly, if your eBook or Video file is faulty or a fault occurs during the eBook or Video being made available to you, i.e. during download then you should contact Customer Relations Team within 14 days of purchase on customercare@packt.com who will be able to resolve this issue for you.
  3. You will have a choice of replacement or refund of the problem items.(damaged, defective or incorrect)
  4. Once Customer Care Team confirms that you will be refunded, you should receive the refund within 10 to 12 working days.
  5. If you are only requesting a refund of one book from a multiple order, then we will refund you the appropriate single item.
  6. Where the items were shipped under a free shipping offer, there will be no shipping costs to refund.

On the off chance your printed book arrives damaged, with book material defect, contact our Customer Relation Team on customercare@packt.com within 14 days of receipt of the book with appropriate evidence of damage and we will work with you to secure a replacement copy, if necessary. Please note that each printed book you order from us is individually made by Packt's professional book-printing partner which is on a print-on-demand basis.

What tax is charged? Chevron down icon Chevron up icon

Currently, no tax is charged on the purchase of any print book (subject to change based on the laws and regulations). A localized VAT fee is charged only to our European and UK customers on eBooks, Video and subscriptions that they buy. GST is charged to Indian customers for eBooks and video purchases.

What payment methods can I use? Chevron down icon Chevron up icon

You can pay with the following card types:

  1. Visa Debit
  2. Visa Credit
  3. MasterCard
  4. PayPal
What is the delivery time and cost of print books? Chevron down icon Chevron up icon

Shipping Details

USA:

'

Economy: Delivery to most addresses in the US within 10-15 business days

Premium: Trackable Delivery to most addresses in the US within 3-8 business days

UK:

Economy: Delivery to most addresses in the U.K. within 7-9 business days.
Shipments are not trackable

Premium: Trackable delivery to most addresses in the U.K. within 3-4 business days!
Add one extra business day for deliveries to Northern Ireland and Scottish Highlands and islands

EU:

Premium: Trackable delivery to most EU destinations within 4-9 business days.

Australia:

Economy: Can deliver to P. O. Boxes and private residences.
Trackable service with delivery to addresses in Australia only.
Delivery time ranges from 7-9 business days for VIC and 8-10 business days for Interstate metro
Delivery time is up to 15 business days for remote areas of WA, NT & QLD.

Premium: Delivery to addresses in Australia only
Trackable delivery to most P. O. Boxes and private residences in Australia within 4-5 days based on the distance to a destination following dispatch.

India:

Premium: Delivery to most Indian addresses within 5-6 business days

Rest of the World:

Premium: Countries in the American continent: Trackable delivery to most countries within 4-7 business days

Asia:

Premium: Delivery to most Asian addresses within 5-9 business days

Disclaimer:
All orders received before 5 PM U.K time would start printing from the next business day. So the estimated delivery times start from the next day as well. Orders received after 5 PM U.K time (in our internal systems) on a business day or anytime on the weekend will begin printing the second to next business day. For example, an order placed at 11 AM today will begin printing tomorrow, whereas an order placed at 9 PM tonight will begin printing the day after tomorrow.


Unfortunately, due to several restrictions, we are unable to ship to the following countries:

  1. Afghanistan
  2. American Samoa
  3. Belarus
  4. Brunei Darussalam
  5. Central African Republic
  6. The Democratic Republic of Congo
  7. Eritrea
  8. Guinea-bissau
  9. Iran
  10. Lebanon
  11. Libiya Arab Jamahriya
  12. Somalia
  13. Sudan
  14. Russian Federation
  15. Syrian Arab Republic
  16. Ukraine
  17. Venezuela