Table Of ContentAbdul-Rahman Mawlood-Yunis
Android
for Java
Programmers
Android for Java Programmers
Abdul-Rahman Mawlood-Yunis
Android for
Java Programmers
Abdul-RahmanMawlood-Yunis
PhysicsandComputerScience
WilfridLaurierUniversity
Waterloo,ON,Canada
ISBN978-3-030-87458-2 ISBN978-3-030-87459-9 (eBook)
https://doi.org/10.1007/978-3-030-87459-9
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Iwouldliketodedicatethisbooktomyfamily:
mywifeArkhawan,mydaughterSara,myson
Sipan, my youngest daughter Zylan, my dad
Mawlood-Yunis, and my mom Saadia
Abdullah Haydar.
I would also like to dedicate this book to the
friends of my youth Hawaz, Zana, Arsalan,
Nazir, Shapoor, and Qabil who were
martyred very early in life because of the war
in Iraq, political dictatorship, and extremism.
Their memories will stay with me forever.
Preface
AndroidforJavaprogrammersisaboutlearningAndroidanddevelopingnativeapps
using the Java programming language. The book reflects my expertise and experi-
enceinteachingsoftwareengineering,Java,andAndroidapplicationdevelopment,
as well as 10 years of IT work experience developing stand-alone Java, Web, and
BusinessIntelligenceapplications.
Target Audience
ThebookintendstobeatextbookforintroductoryoradvancedAndroidcoursesto
betaughtinoneortwosemestersinuniversitiesandcolleges.Itusescodesamples
andexercisesextensivelytoexplain andclarify Androidcodingand concepts.The
book will benefit students and programmers who have no prior Android program-
ming knowledge. It is also useful for those who already have some Android
programming skills and are excited to study more advanced concepts or acquire a
deeperknowledgeandunderstandingofAndroidprogramming.
Thebookcanbeeasilyreadandusedbyinstructors.Alltheappsinthebookare
native Android apps and do not need to use or include third-party technologies to
run.Thebookdiffersfromothersthatspendsubstantivetimeexplainingthird-party
software,suchasReactNative,IonicFramework,Flutter,andAppInventortocreate
and run apps. Our approach is to stay focused on using Android and native apps,
somethingimportantwhenlearningAndroidforthefirsttime.
Topics and Teaching Approach
Foreachchapter,oneortwodemoappsaredevelopedtodemonstratetheconcepts
discussed. The source codes of the demo apps are available for download from
the book’s website (https://github.com/amawloodyunis). The executable codes,
vii
viii Preface
i.e., .apk (Android application package), are also available for download. I recom-
mend that you re-create the demo apps following the instructions provided in the
bookinsteadofjustopeningthesourcecodesinAndroidStudioandrunningthem.
You will learn more by doing it yourself, i.e., by re-creating the demo apps
incrementally and using the provided source codes as a reference to debug and fix
anyissuesyoumightface.Onceyouaredonereadingthisbook,Iexpectyoutobe
able to develop and publish apps on Google Apps Store, Samsung Apps Store,
AmazonOnlineStore,andF-Droid.
Each chapter of the book is dedicated to one or more Android development
topics. Each app hasa main interface withtwo ormore buttonson the first screen.
When clicked, each button starts a stand-alone app. We followed this approach to
consolidateallappsforeachchapterintooneproject.However,ifyouwish,youcan
createmultiplesmallprojectsbycopyingpartsofthechapterappandusingthecode
tocreateeachseparatestand-aloneapp.Althoughwecovertheimportantfeaturesof
each topic, they are not all-inclusive. There is space for further expansion of each
topic.ThetopicscoveredincludeActivitiesandtransitionsbetweenActives,Intents,
Bundle objects, Activity lifecycles, callback methods, Android user interfaces and
Widgets, Activity layouts, Toolbars and Menus, Cursor objects, the Android Pro-
filer, the Device File Explorer, Android Debug Bridge (adb), Toast and Snackbar
message objects, the Log class and the LogCat utility, testing, Parcelable objects,
Fragments,DateandTimePickers,SharedPreferences,databases,XMLandJSON
processing,theContentProvider,theRoomlibrary,theAndroiddirectorystructure
and access to local and external files, Services and broadcasting, AsyncTask and
threading, Broadcast Receivers, MediaPlayer, VideoView, location and motion
Sensors, Android map and tracking, language and Locale settings, Android
measurements,etc.
Content and Explanation
The book is unique in terms of its content, content explanation, approach, and
structure. To emphasize the importance of app design, documentation, code main-
tenance,andevolvingcode,weincludeclassstructuresformostoftheappscreated
in the book. We also explain concepts such as code profiling, test coverage, and
reverseengineering.Whilethesetopicsareimportanttocreatehigh-qualitybusiness
apps,theyarerarelydiscussedinAndroidbooks.Myobjectiveistogobeyondthe
simple app explanations that are typically found in Android development books.
Here, we help the reader to think of all aspects of software engineering to create
robustandmaintainableapps.
The book provides a deep explanation of what is beneath Android concepts in
termsofJava.Forexample,whileitisfundamentalforAndroidappdevelopmentto
havealayoutandcreatethelayoutforActivitiesintheXMLfile,weshowhowyou
canachievethesameresultswithoutcreatingalayoutintheXMLfile.Thisapproach
Preface ix
deepensthereader’sunderstandingofwhatisbeneaththeAndroidhood,something
notoftenfoundoraddressedinAndroidbooks.
Someoftheappsincludedinthisbooksolvereal-worldproblems.Forexample,
inChap.11,thelivestreamingappcreatedusingURLsenablesone’sfavoriteradio
stations to be grouped in one place and, hence, easily played and switched from
another. It is an app that turns your device into a radio and lets you listen to live
streamingstationswhileintheoffice,ontheroad,orinanyothersetting.Theappis
similar to Spotify but on a smaller scale. Other apps in the book provide you with
real-timeweatherinformationforallthecitiesinCanadaandCovid-19data.Wealso
addfurtherguidancetocreateappsthatobtainnewsinformation,currencyexchange
rates,informationaboutyourlocalpoliticalrepresentationingovernment,etc.
The structure of the book follows Java and Object-Orient (OO) programmers’
expectations.JavaandOOprogrammersarefamiliarwithconceptssuchasclasses,
interfaces,methods,methodcalls,andpassingvaluesandobjectsbetweenmethods,
and when they come to learn Android, they look for mapping between what they
knowandwhattheyaretryingtolearn.Thatis,theylookforequivalentconceptsin
thenewAPItheyareabouttolearn.OurbookisstructuredinawaytohelpJavaand
OO programmers easily map Android concepts to their own. For example, in the
early chapters of the book, we cover Parcelable objects, which are equivalent to
objectserializationforpassingobjectsbetweenActivities.Wealsointroducegoing
backandforthbetweenActivities,whichisequivalenttonavigatingbackandforth
betweenJavaframesorHTMLwebpages.
Latest Code
Animportantaspectofteachingandlearningistostayuptodate.Thisisespecially
thecaseforafieldofstudythathasbeengoingthroughalotofchanges,wheresome
of these changes are philosophical ones. For example, Google recently made
changes to the way services run in the app’s background, how the permission is
checked to read/write the files, and how to access local resources and location
services. These changes make explanations provided in any Android book written
beforethem,someofthesechangesbeingmadein2018,invalidandtheirassociated
codetobeunusablewithoutasubstantiveredo.Allcodesofthisbookareuptodate.
They are implemented in the latest Android SDK version and the latest published
AndroidStudio.
Enjoy.
x Preface
Additional Resources for Users and Instructors
Users can download the source codes of the demo apps from here: https://github.
com/amawloodyunis. In addition, instructors can download chapter presentations
in PTT and PDF formats by request. The email for contact is
[email protected].
Convention Used in the Book
Weuse... notationtoindicatethattheusershouldwritetheircodeinthisplace.
Waterloo,ON,Canada Abdul-RahmanMawlood-Yunis
July2021
Acknowledgments
I would like to thank my daughter, Sara Mawlood-Yunis, for the reviews and
contributions she made. Her input has been priceless. I would like to also thank
mycolleague,ProfessorIliasKotsireasfromWilfridLaurierUniversity,forhishelp
and encouragement to write this book. I also would like to thank Ralf Gerstner,
Sharanya Sakthivel, Ramya Prakash, and others from Springer who worked tire-
lesslytoimprovethemanuscriptofthisbook.
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