android.md

Android

Table of Contents

• Books
• Development frameworks
• Guidelines
  • Java
  • Kotlin
• IDEs
• Libraries
  • Crash Reporting Libraries
  • Dependency Injection Libraries
  • HTTP Libraries
  • Image Loading Libraries
  • JSON Parsing Libraries
  • NoSql Databases
  • ORM Libraries
  • Testing
    • Automation
    • Code Coverage
    • Mocking
    • Static Code Analysis
    • Unit Testing
• Roadmaps
• Terminology

Roadmaps

• https://github.com/tientnvn/android-developer-roadmap

Guidelines

• Android Design Guidelines
• Why the app can be rejected on Play Store

Java

• Android Code Style Guidelines
• Google Java Style Guide
• Oracle Secure Coding Guidelines for Java SE

Kotlin

• Kotlin style guide

Libraries

Testing

• Test your app with Android Studio

Code Coverage

• SonarQube
• Cobertura
• Emma
• Jacoco
  • Can be run with Ant and Gradle.
  • Has well formatted and detailed html reports.
  • Easy to integrate with Robolectric.
  • By default calculates coverage for instrumentation tests only. For unit test coverage use jacoco-android-gradle-plugin.

Components Comparison

• Coverage Types – which types of code coverage tool suports (line/class/method/block/statement/branch).
• Ease of use – how easy to configure and work with it (easy/ not easy).
• Access to the source code – whether a tool requires source code to generate code coverage (yes/no).
• Defined in Android SDK – whether a tool is in Android SDK (yes/no) .

Component	Pricing	Report Types	Coverage Types	Ease of Use	Access to the source code	Defined in Android SDK	Documentation Quality
Clover	paid	xml, html, pdf, json	line, statement, branch, method	not easy	yes	no	good
Cobertura	free	html, xml	line, statement, branch, method	not easy	yes	no	no
Emma	open source	html, xml, plain text	line, block, method, class	easy	no	yes	average
Jacoco	free	xml, html, csv	line, method, branch, class	easy	yes	no	average

Unit Testing

• JUnit - Android native test suite

Mocking

• Robolectric
  • allows for tests to be run in the JVM instead of the DVM by replacing the native Android calls with proxies.
  • one of the most TDD-suitable testing frameworks
• Mockito
• EasyMock
• PowerMock

Components Comparison

Component	Running on Device	Performance	Documentation Quality	final/static support
easymock	yes (with extention)	Good	Average	no
mockito	yes (with extention)	Good	Good	no
powermock	no	Good	Average	yes
robolectric	no	Best	Good	no

Static Code Analysis

• Android Lint
• SonarQube (cross-platform)

Automation

Appium is very flexible and stable framework. Prefer this framework to create good architecture and work with web, native and hybrid apps

Components Comparison

Component	Native Apps Support	Hybrid Apps Support	Web Apps Support	Starts the Emulator	Supported Languages	Supported Platforms	Documentation Quality
Appium	Yes	Yes	Yes	Yes	Java, Objective–C, JavaScript with Node.js , PHP, Python, Ruby, C#, Clojure, or Perl	iOS, Android, FirefoxOS	Good
Calabash	Yes	Yes	No	No	Ruby + Plain text	iOS, Android	Average
Espresso	Yes	No	No	Yes	Java	Android	Average
MonkeyTalk	Yes	Yes	No	No	Java or Javascript, native language	iOS, Android	Average
Robotium	Yes	Yes	No	Yes	Java	Android	Good
Selendroid	Yes	Yes	Yes	Yes	Java, Objective–C, JavaScript with Node.js , PHP, Python, Ruby, C#, Clojure, or Perl	Android	Good
UIAutomator	Yes	No	No	No	Java	Android	Good

HTTP Libraries

• OkHTTP - best as a General purpose HTTP library (allows to perform generic HTTP requests: select an HTTP method, build headers and a request body). It provides a variety of features and is deeply customizable.
• Retrofit - best as REST client application component (helps to interact with the REST services). Simplifies web service methods proxy building. It is easily used in conjunction with OkHTTP library.

Components Comparison

Component	Functionality	Objects Mapping Support	Data Caching	Authenticaion Support	Documentation Quality	Android Only
Google APIs Client	Good	Yes	Yes	Yes (OAuth 1 and 2)	Average	No
Google HTTP Client	Good	Yes	Yes	No	Average	No
OkHTTP	Good	Yes	Yes	No	Average	No
Retrofit	Good	Yes	Yes	No	Average	Yes
Spring for Android	Good	Yes	No	Yes (OAuth, Twitter, Facebook)	Good	Yes
Volley	Good	No	Yes	Yes	Average	Yes

Image Loading Libraries

• Glide or Picasso are the best to download and put the image in the app, you don't need a lot of configuration and they can work with almost every popular image format. You can also add listeners and callbacks easy.
• Glide has the best to download and apply some effects, it's build to give better appareance when showing the image and to work better with lists of items.
• Fresco is best to load different formats and customize the download process. Supports GIF, WebP and animated WebP. Glide can also work with GIF.

Components Comparison

Component	Support of External HTTP Clients	Set of Transformations	Documentation Quality
Fresco	Yes	Good	Good
Glide	Yes	Good	Good
imageloader	No	Good	Average
Picasso	Yes	Average	Average (Javadoc)

JSON Parsing Libraries

GSON and Jackson are complete JSON parsers:

• Generate JSON data
• Data binding (Primitive data types, Maps, Lists and Objects)
• Support Stream (SAX like but not event-based) and Tree (DOM like) parsing techniques
• Support annotations

Components Comparison

Component	Usage and Integration	Performance for Small/Large Data Size	Parser Customization	Plugins	Supported by Network libs
GSON	Easy	Fast / Medium	Basic	No	Yes (Most of them)
Jackson	Medium	Medium / Fast	Yes	Yes	No (Limited number)

Crash Reporting Libraries

• Crashlytics - free full-featured crash reporting tool. Integrated with Firebase.

ORM Libraries

• ORM is Object-Relational Mapping here.
• Room from Google - provides an abstraction layer over SQLite to allow for more robust database access while harnessing the full power of SQLite.
• OrmLite - provides excellent functionality and wide set of features.

NoSql Databases

• Realm is a modern NoSql framework.
  • It uses its own persistence engine, built for simplicity (& speed).
  • Rich functionality (that increasing very fast)
  • Excellent possibilities for customization.
• Firebase Database
• Firebase Firestore

Dependency Injection Libraries

Dagger - high quality functional DI framework.

Components Comparison

Criteria:

• Functionality – richness of functionality and possibilities for customization (good/average/bad).
• Overhead – how large does become a project when using the library and how does this affect application memory(small/medium/large).
• Android injections – whether the framework supports Android platform specific features e.g. view injections, resource injections. (yes/no).
• Injections mode – whether the framework works at runtime or at compile time(runtime/compile).
• Documentation quality – how good a tool and its features are documented (good/average/bad).

Component	Functionality	Overhead	Android injections	Injections mode	Documentation quality
AndroidAnnotations	Good	Medium	Yes	Compile	Good
Dagger	Average	Medium	No	Compile	Good
RoboGuice	Good	Large	Yes	Runtime	Average
Transfuse	Good	Medium	Yes	Compile	Average