1. Android for Java Developers Denver Java Users Group Jan 11, 2012 -Mike Wolfson @mikewolfson

2. Why Android? Open APIs – everyone’s equal Low Barrier to entry Run app on your own device - $0 Sell through Google Market - $25 Easy to develop apps Especially for Java Developers Platform agnostic Open Market (or download from anywhere) Feature Rich platform

3. Framework Overview http://developer.android.com/guide/basics/what-is-android.html

4. Framework – Linux Kernel Core system services Handles security, memory management, process management, network access, etc Abstraction layer between OS and hardware

5. Framework - Dalvik Virtual Machine Optimized for mobile devices Every app runs in its own instance of VM Runs classes compiled by Java, and transformed into.dex files

6. Framework - Libraries Variety of libraries to provide built in functionality.

7. Framework – Application Framework Provides functionality to allow Applications to interact with underlying OS and other applications Designed to simplify the reuse of components, and allow applications to publish, or make use of the capabilities of other applications

8. Framework – Applications The layer where custom-built applications live. This is the place where most mobile developers will interact with Android. Your App Here!

9. Framework Overview

10. Get Developer Tools SDK http://developer.android.com/sdk/index.html Requires Java SDK (5.0 +) Updating versions What the different versions mean ADT Plugin (for Eclipse) http://developer.android.com/guide/developing/tools/adt.html Need Eclipse Ganymede (3.4+) Update site: https://dl-ssl.google.com/android/eclipsehttps://dl-ssl.google.com/android/eclipse Can develop without Eclipse

11. Developer Tools (cont ) Android command Emulator Android Virtual Devices (AVD) Android Debug Bridge (ADB) Command line tool for interacting with phone/emulator. Dalvik Debug Monitor Server (DDMS) Debugging tool providing: screen capture, memory info, logging, info spoofing) http://developer.android.com/guide/developing/tools/index.html

12. Developing an App 1. Create a new project Project content overview 2. Code 3. Test on emulator (or device) 4. Debug 5. Sign 6. Export to device As APK (Android PacKage file)

13. Terminology Most Commonly used elements Activity Intent Manifest file Resources and Assets Layout Fragment

14. Terminology - Layout Layout – describes the UI of an activity Enables separation of UI from logic There are a variety of layouts you can use including: Linear, Table, Relative, and Frame

15. Terminology - Activity Activity – (Noun) A single screen, your application is made up of one or more of these. Always extends Activity

16. Terminology - Intent Intent – (Verb) code to perform an action Wiring between activities, services, broadcast receivers, or other functions facility for late run-time binding between components in the same or different applications Rich set of Intent in Android provide excellent way of executing specific actions

17. Fragments Fragments represent a behavior or portion of a UI. Designed to collect a unit of UI and behavior into a reusable component Don’t have own lifecycle – and must be embedded in an Activity

18. Fragments

19. Terminology - Manifest Manifest File – describes your app always named AndroidManifest.xml declares the components of an application, describes security permissions required by the app, and lists required library dependencies

20. Terminology - Resources Resource – text, pictures, sound, etc are all abstracted from the code and logic compiled and managed by system generated R.class file Instantiate by getting reference to object

21. Resources Multiple Layouts and Graphic Assets Can also be Used for language localization Tip: use Density Independent Pixels (DP) Draw9Patch

22. Terminology - APK Android Application File User can install apps from many sources Developer can upload updates easily

23. Terminology – cont. Other important elements Widget Service Broadcast Receiver Security and Permission Content Provider

24. Learn More http://developer.android.com Denver Droids http://www.denverdroids.com/ http://forum.xda-developers.com http://www.stackoverflow.com http://developer.android.com Google Groups (Forums)

25. Questions? @mikewolfson Google +: Mike Wolfson mwolfson@gmail.com Slideshare: http://www.slideshare.net/mswolfson Dropbox: http://dl.dropbox.com/u/23589031/DJUG.zip Beer?!