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Unlocking Android 117

Michael J. Ross writes "Of all the potential challengers to Apple's phenomenally popular iPhone, perhaps the one with the best prospects is Google's Android, which is not a mobile phone per se, but rather an open-source platform that the company encourages phone manufacturers to deploy in their own products. Similarly, Google encourages computer programmers to develop applications for the Android environment. But learning how to create such applications is daunting to the uninitiated, particularly for developers who have never before worked with the user interface controls, Web services, and other resources involved. A recently published book, Unlocking Android, is designed to help such developers." Read below for the rest of Michael's review.
Unlocking Android
author W. Frank Ableson, Charlie Collins, Robi Sen
pages 416 pages
publisher Manning Publications
rating 8/10
reviewer Michael J. Ross
ISBN 978-1933988672
summary A guide to developing applications for Google's Android.
Unlocking Android was put out by Manning Publications on 28 May 2009, under the ISBN 978-1933988672. It was authored by W. Frank Ableson, Charlie Collins, and Robi Sen — all of whom have extensive experience in developing mobile software applications. The publisher's Web page makes available author biographies, descriptions of the book, all its ancillary parts (the foreword, preface, acknowledgments, table of contents, and index), a white paper on Android (oddly termed a "green paper"), and two sample chapters ("Targeting Android" and "Intents and services"). There is a link to download the source code from the Google Code site, organized by chapter. The Manning site also hosts a forum, where readers and the authors can discuss the book. As of this writing, there are 42 threads, comprising 120 messages. Lastly, the site has links to order both the print and electronic versions of the book. Note that purchasing the former automatically entitles one to a copy of the latter. Manning appears to be pioneering this approach to making e-books more readily available to customers, since every print copy now contains an insert with a list of codes that can be used to download a PDF copy of the book.

The book is ostensibly intended for Android beginners, even though it does contain enough detailed information to serve as a partial reference for more experienced developers. It is organized in a logical fashion, in three parts, starting with an overview of Android itself, both the technology and the organization behind it. Then the reader is introduced to the Android programming environment, along with its many components and capabilities. The book concludes with tutorial chapters that step the reader through creating a sample Android application and more. The material covers Android SDK 1.x. Since Android programs are written in Java, any reader fluent in that language will have a much easier time absorbing the ideas. However, the authors state that even non-Java programmers should be able to follow the examples, as long as they have knowledge of similar languages, such as C, C++, or C#. However, even a cursory glance at the code, by such a reader, would prove that Java knowledge is essential.

The first chapter — oddly named "Targeting Android" — introduces the platform, the organizations behind it, the mobile market as a whole, Android's features, how it differs from featured phones and smartphones, its open-source licenses, platform components, libraries, service managers, programming environment, and virtual terminal. Be warned that Figure 1.1 could be confusing to some readers, because it shows the layers of technology that compose the Android platform, but pictures them on the front of a mobile phone, showing a keypad, which makes the layers appear to be part of the actual user interface; the phone should be removed from the illustration, in a future edition. The chapter goes on to discuss booting and activating Android, as well as how to map applications to processes. Some readers anxious to get to the technical nitty-gritty, may become impatient when reading the first portion of this chapter, because it largely consists of introductory material. Yet this context can be helpful and interesting to people unfamiliar with the mobile phone market. (Articles and tutorials aimed at new mobile application developers, oftentimes assume that said developers are already extremely familiar with the rapidly changing mobile market.) In the later portion of the chapter, readers are shown a handful of code snippets, with some explanation as to what they are doing and how. In reading this material, the reader could be easily overwhelmed with all of the new terminology. One can only hope that the authors were not thinking that the typical reader would understand all of what is discussed, or be able to do anything with it. A canonical "Hello, world" program or something similar — with an explanation as to how to execute it — would have been a far more gentle introduction. By the way, the first few code snippets are poorly indented, and some of the method names are italicized, while others are not — with no mention as to what this might signify, either in the chapter or in the earlier "Code Conventions" section.

In Chapter 2, the reader is introduced to the key tools for basic Android development, including the SDK, Eclipse, and the Android Emulator. An example application — a tip calculator — is developed, step by step, to illustrate those tools. Clearly, this tutorial information should have been presented before the second section of the previous chapter. It nonetheless serves as a valuable introduction to programming Android. Incidentally, Figure 2.1 labels the development environment as being located on a laptop, incorrectly suggesting that desktop computers are not equally usable platforms. Later, when the authors suggest that readers add the Android SDK tools directory to their system search path, they specify only the release-independent directory (containing adb, for instance), and not the release-specific paths (containing aapt, which is the first tool discussed); readers presumably should add both. Also, the authors should specify which release to use, 1.1 or 1.5. The reader eventually is told how to run a sample application — and not a moment too soon, because at that point the reader is already 15 percent of the way into the book. To reach that point, she must wade through more introductory material than was needed, in addition to discussions of network speed and latency, command line tools, DDMS, Java packages, and other information. All of this could and should be covered later, when it would be much more meaningful, and the reader would have greater motivation to learn it, having seen an Android application running (if only in the emulator).

Part 2 forms the bulk of the book, consisting of nine chapters devoted to the essential aspects of Android application development: user interfaces, including the Activity class, views, resource types, and manifest files; Intent classes, broadcast receivers, task services, and inter-process communications; data storage and retrieval, including user preferences, files stored on the local system and on SD cards, databases, and the ContentProvider class; networking, including client/server interaction, HTTP, and Web services such as SOAP; telephony, including how to receive and initiate calls and SMS messages; notifications and alarms; generating graphics and animation; multimedia, including audio and video, utilizing the OpenCORE technology; location-based applications, using a variety of tools, including Google Earth's KML. All of these chapters make use of example applications, with annotated source code and screenshots of the applications running in the Android emulator.

The third and final part of the book comprises two chapters, each of which extends the core concepts of Android development. Chapter 12 steps the reader through the creation of a substantial application, named "Field Service Application," designed for mobile technicians who provide support services for customers of contracted clients. The application is designed to be used by both the technician and his home office to assign and manage job orders, capture customer signatures of completed jobs, order replacement parts, and receive navigation assistance. The final chapter, "Hacking Android," explores Android's utilization of Linux, the C programming language, and the SQLite database — as well as how the Android developer can access these capabilities under the hood.

Appendix A explains how to install the Eclipse integrated development environment (IDE), the Android software development kit (SDK), and the ADT plug-in for Eclipse. Readers who do not already have those components installed on their computers, may want to first read the appendix and follow the procedures. Note, however, that the procedures given in section A.4, for installing the ADT plug-in, are already out of date — namely, for Eclipse version 3.3. In addition, the URL given by the authors ("") is invalid, because it is missing the trailing directory slash, which is necessary for it to work within Eclipse. (This points up the importance of including root directories in URLs, despite their common absence, because even though Web browsers will automatically correct this upon receiving an error message from the server, Eclipse evidently does not.) The online Android installation instructions are much more useful, because they also include the latest version of Eclipse, 3.4.

As is to be expected with the first edition of any detailed computer programming book, this one contains some errata — for instance, in the first portion of the book alone: "Android[']s" (page xxii, twice), "Webkit" (page 7, in the caption), "SQLite[,] an" (page 11), and "byte code[s]" (page 13). Also, terms such as "Internet" and "Web" are in all-lowercase, throughout the book, even though they are proper names. (In our world of instant messaging and Twitter, grammatical degeneration continues apace.) For any reader who wishes to follow along and implement the sample projects, possibly the most disappointing decision by the authors was that of offering the sample code not as a single archive file, or even individual archive files for each of the 13 chapters. Instead, the reader must tediously click through multiple layers of directories, just to get the code displayed in a browser, one file at a time. Readers are advised to employee a Web copying utility, which, given a starting URL, will try to download all of the linked pages, recursively, and store those Web pages and other Web elements on their own computer (even localizing links, to retain working navigation in the saved pages).

Yet by far the biggest problem with this book, is that while it claims to be an introductory text, suitable for someone completely unfamiliar with Android, it does not bring the newcomer up to speed at a reasonable pace for learning. Instead, it presents a large number of code snippets and tools to the reader, without adequate explanation for the beginner to truly understand what is happening. This pattern begins even in the first chapter, which is sorely lacking a tutorial on how to execute the sample code — to better understand it and perhaps modify it (a practice that most programmers find quite valuable for assimilating a new technology). On page 23 is a frustratingly brief sidebar on testing the receipt of an SMS message, that is far from adequate for the reader anxious to begin testing out this new material. The second chapter continues this unfortunate tendency of describing tools prior to giving the reader enough information to run those tools themselves in the same manner, and see the same results. For instance, on page 41, the authors show how to use the adb tool to connect to a running emulator session, but at that point the reader has no such sessions running. (Sometimes the authors of programming books understand the material quite well, but neglect to view it from the perspective of someone who does not yet have that understanding.)

While more appropriate for intermediate Android developers than claimed, Unlocking Android contains a wealth of information to help Java programmers begin developing mobile applications for Google's new platform, with numerous code snippets and screenshots.

Michael J. Ross is a freelance Web developer and writer.

You can purchase Unlocking Android from Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.


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Unlocking Android

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  • by goffster ( 1104287 ) on Monday June 29, 2009 @02:36PM (#28517427)

    If you buy an unlocked android phone, you can not run applications *you paid for*
    because of DRM.

    If you buy an android phone and then unlock it, all is well.

  • eclipse (Score:4, Informative)

    by LDoggg_ ( 659725 ) on Monday June 29, 2009 @02:39PM (#28517457) Homepage
    The online Android installation instructions are much more useful, because they also include the latest version of Eclipse, 3.4.

    Actually 3.5 (Galileo) is out now. There aren't explicit instructions for it on, but it's still works the same way. Add the update site, and install the plugin.
  • by spyingwind ( 961097 ) on Monday June 29, 2009 @02:49PM (#28517621) Homepage
    "If you buy an unlocked android phone, you can not run applications *you paid for* because of DRM." This is a false statement unless your referring to a non Dev phone I have IM+ paid for and I am using it with out a fuss on my Dev phone. ~Spyinwind
  • by Anonymous Coward on Monday June 29, 2009 @03:27PM (#28518175)

    I have a G1, and have the following complaints about it: 1) Slow response to input touch 2) No support for Bluetooth stereo profile (has this been fixed yet?) 3) It tends to do things like call people and display youtube videos without me telling it to (do other touchscreens have this problem?) 4) GPS receiver is less sensitive than iPhone (this might be just my specific phone)

    Battery life? Yeah, you have to recharge it _every_ night, but it has no problem making it through a full day's use. "On par with the iPhone"? Hardware/feature wise, yes. Software wise, the iPhone has been longer in development, so it is more ready for prime time and has more apps available. I bought the G1 betting that Android software would improve faster; it may yet surpass iPhone but to date I have been disappointed by the rate of improvement.

    Biggest problem with both phones? iPhone is tied to AT&T and G1 is tied to Tmobile. I would LOVE to see and end to the exclusive deals between mobile manufacturers and cell phone providers.

  • by TheBracket ( 307388 ) on Monday June 29, 2009 @04:03PM (#28518681) Homepage

    I have a g1 sitting here, running on AT&T. It was unlocked by purchasing an unlock code from a website - and all the market apps I've downloaded (including some for which I paid, such as Touchdown's Exchange client - need it for work) work just fine. I think the problem referred to above isn't with market apps you buy on the newly unlocked phone, but with losing access to already-purchased apps when you unlock; I'm not sure about that since this phone was wiped before I unlocked it.

  • I've published an Android app (Slicehost), as well as a few iPhone apps, and here are the biggest differences in development that ultimately (in my opinion) make Android apps inferior:

    1. It's Java + Eclipse, which is notoriously slow when compared to XCode and the iPhone Simulator
    2. UI design is done in very verbose XML, as opposed to Apple's Interface Builder, which lets you easily drag things where you want them
    3. Since Android is a platform and not tied to a single device, you have to design in "device independent pixels" which is much different than the iPhones set-in-stone 320x480 resolution
    4. Core Animation... 'nuff said
  • by $1uck ( 710826 ) on Monday June 29, 2009 @04:06PM (#28518781)
    It doesn't use a JVM is uses Dalvik vm. SO it is something more than a typical j2me vm and something less than a full JVM. It has its own windowing tool kit, it does not use awt or swing or swt. Personally I think the Android OS is pretty slick, inter-application communication is interesting.

Heuristics are bug ridden by definition. If they didn't have bugs, then they'd be algorithms.