1. Froyo to KitKat
Two Years Developing & Maintaining DeliRadio
by Andy Dyer

2. About Me
• Android & Rails developer at ChaiOne in Houston, Texas, USA
• Android apps on Google Play - DeliRadio, Music Library, and
Wrist Presenter
• Hobbies/Interests - Vinyl collector, coffee & beer snob, burger
aficionado
• Ich lerne Deutsch

4. About DeliRadio
• Explore local concert
calendars
• Stream stations based on
location or specific venues
• Share discoveries with
friends
• Receive notifications when
favorite artists play nearby

5. About DeliRadio - Navigation & Filters

6. About DeliRadio - Server Architecture
• Sinatra/Ruby API used by Android, iOS, and
third-party clients
• Virtual private cloud
• Web, database, and job servers
• Hosted on Amazon S3 & CloudFront CDN
• ElasticSearch & Redis for caching & high
performance search

7. Supported Android Versions Over Time
Early 2012
Min: Froyo
Max: Honeycomb
Mid 2012
Min: Froyo
Max: ICS
Early 2013
Min: Gingerbread
Max: Jelly Bean
Early 2014
Min: ICS
Max: KitKat

8. Topics
• Development Tools & Build Process
• Libraries Used
• Graphics & User Interface
• QA & Testing

9. Topics
• Development Tools & Build Process
• Libraries Used
• Graphics & User Interface
• QA & Testing

10. Development Tools (Early to Mid 2012)
Eclipse
• But which one?
• Build System: Ant
• Dependencies:
JAR files or
Maven (if you’re
patient)

11. Development Tools (Mid 2012 to Mid 2013)
Android Developer Tools (ADT) Bundle
• Android specific version of Eclipse
• Slightly more lightweight

12. Build Process - Eclipse & ADT
• Initial approach - File > Export, manually enter
keystore password, etc.
• Slightly better approach - Template based Ant
build
• Release & debug resources
• Custom Ant build targets with config specific
tokens
• Templates for manifest and other source files

13. Build Process - Eclipse & ADT
Problems with this approach
• Non-standard
• Templates must be be updated instead of
main files (i.e. manifest gets overwritten with
populated template on each build)
• Switching between release & debug must be
done via the command line. IDE just builds
current files.

14. Development Tools (Mid 2013 to Present)
Android Studio
• Gradle
• Maven dependencies - Similar to Ruby Gems

15. Build Process - Android Studio
Gradle
• Release & debug resources - automatically
merged during build process, no need for
templates
• Automated signing & version code
incrementing for release builds
• Automatic upload of test builds to Test Fairy

16. Gradle Build - Config-Specific Resources
android {
!
// ...
!
sourceSets {
debug {
manifest {
srcFile 'gradle/debug/AndroidManifest.xml'
}
res {
srcDir 'gradle/debug/res'
}
}
!
release {
manifest {
srcFile 'gradle/release/AndroidManifest.xml'
}
!
res {
srcDir 'gradle/release/res'
}
}
}
!
// ...
!
}

17. Gradle Build - Release Signing
android {
!
// ...
!
signingConfigs {
release {
storeFile file("../my_keystore.jks")
storePassword "$up3r$3cr3t"
keyAlias "my_key_alias"
keyPassword "$up3r$3cr3t"
}
}
!
buildTypes {
release {
signingConfig signingConfigs.release
}
}
!
// ...
!
}

18. Gradle Build - Version Code Increment
def versionMajor = 1
def versionMinor = 0
def versionPatch = 0
!
task('increaseVersionCode') << {
def manifestFile = file("src/main/AndroidManifest.xml")
def pattern = Pattern.compile("versionCode="(d+)"")
def manifestText = manifestFile.getText()
def matcher = pattern.matcher(manifestText)
matcher.find()
def versionCode = Integer.parseInt(matcher.group(1))
def manifestContent =
matcher.replaceAll("versionCode="" + ++versionCode + """)
manifestFile.write(manifestContent)
}
!
tasks.whenTaskAdded { task ->
if (task.name == 'generateReleaseBuildConfig') {
task.dependsOn 'increaseVersionCode'
}
}

19. Gradle Build - Version Code Increment
android {
!
// ...
!
defaultConfig {
minSdkVersion 14
targetSdkVersion 19
versionName "${versionMajor}.${versionMinor}.${versionPatch}"
}
!
// ...
!
}

20. Gradle Build - Test Fairy Upload
buildscript {
repositories {
mavenCentral()
maven { url 'https://www.testfairy.com/maven' }
}
!
dependencies {
classpath 'com.android.tools.build:gradle:0.10.+'
classpath 'com.testfairy.plugins.gradle:testfairy:1.+'
}
}
!
apply plugin: 'android'
apply plugin: 'testfairy'
!
android {
testfairyConfig {
apiKey "1234567890abcdef"
}
}
!
!
gradlew testfairyDebug
https://github.com/testfairy/testfairy-gradle-plugin

21. Topics
• Development Tools & Build Process
• Libraries Used
• Graphics & User Interface
• QA & Testing

22. Libraries Used - API (Early 2012 to Mid 2013)
• Apache HTTP Client - API requests
• Ignition Library - Caching & async image
loading
• GSON - JSON parsing

23. Libraries Used - API (Mid 2013 to Present)
• Volley - API requests & caching
Pro Tip:
compile 'com.mcxiaoke.volley:library-aar:1.0.+'
• Picasso - Async image loading
• GSON & Jackson - JSON parsing
• Apache HTTP Components - File uploads

24. Libraries Used - User Interface
• Smooth Progress Bar - Dashed progress bar
similar to Gmail, etc.
• Sticky List Headers
• View Pager Indicator

25. Libraries Used - User Interface
• Butter Knife - View Injection
!
!
@InjectView(R.id.profile_username) TextView username;
!
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.my_fragment, container, false);
ButterKnife.inject(this, view);
return view;
}

26. Libraries Used - Social Networks
• Facebook SDK
• Twitter4J
• Signpost - Twitter OAuth flow

27. Libraries Used - Miscellaneous
• Google Play Services - Battery friendly
location
• GreenDAO ORM - Much simpler than content
providers
• Otto - Event bus, pub/sub messaging between
components
• Crashlytics - Crash reporting & analysis

28. Topics
• Development Tools & Build Process
• Libraries Used
• Graphics & User Interface
• QA & Testing

29. Graphics & User Interface
• iOS design != Android design - But iOS 7
blurred the lines
• Retina images - XHDPI
• Non-Retina images - MDPI
• Icon font - Scalable icons that can be styled as
text

32. Graphics - Using an Icon Font
1. Use Font Awesome web font or your own font
for scalable, styleable icons
2. Map font characters in a strings resource file
3. Load font, apply to TextView or Button subclass
4. Set view text to desired character, style, etc.
5. Bask in the awesome
!
https://github.com/bperin/FontAwesomeAndroid

33. Graphics - Icon Font in Layouts
<com.FontAwesome.Example.TextAwesome
android:id="@+id/text_prost_icon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/fa_beer"
android:textSize="30sp" />
!
!
<com.FontAwesome.Example.ButtonAwesome
android:id="@+id/button_kaffee_icon"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/fa_coffee" >

35. User Interface - Multiple Screen Sizes
• Use ActionBarCompat & Nine Old Androids if
supporting Gingerbread or lower
• Use RelativeLayout where possible to
dynamically position views
• Dimensions in dimens.xml files, different
values directories for various screen sizes
• Screen size specific layouts where necessary

36. Topics
• Development Tools & Build Process
• Libraries Used
• Graphics & User Interface
• QA & Testing

37. QA & Testing - Devices
• Too many to test them all
• Attempt to test a representative sample
• Major manufacturers - HTC/Motorola/
Samsung/Nexus
• After Gingerbread support dropped, OS version
& OEM customizations are much less of an
issue

38. QA Testing - Process
• Bugs & features entered in Pivotal Tracker
• Multiple builds delivered for testing each week
• Use Test Fairy test session videos to
troubleshoot device specific issues
• Full regression test of RC build before each
release

39. Vielen Dank!
K andydyer.org
n @dammitandy
g plus.google.com/+AndrewDyer