Android Hands-On
by several Googlers:
Android phones were handed out like candy.
(a bit dated, but still good)
http://developer.android.com (for app development)
http://source.android.com (for the os)
Agenda
- What make a great app?
- UI design tips
- Developing REST client apps
- Porting existing C codebases
- Lots of Q&A time at the end
What make a great app?
Roman Nurik
1) Speed, responsiveness
- Use AsyncTasks and Services
2) Quality/Polish
- Clean, flexible, beautiful UI
- Feature completeness
- Stability and error resilience
3) System UX integration
- Widgets, notifications, live folders, Quicx Search box, accounts, sync, etc
- Intuitive and correct navication, proper use of back, menu, search buttons
Bonus: Cross-app integration
- Exposing public intents, content providers, URL schemes, etc
User Interface Design Tips
1) Dos/Dontshttp://oscon2010.blogspot.com/2010/07/android-what-wherefores.html
- Don't simply port from other platforms
- Do create versions of all resources for high density screens
2) Design philosophy and considerations
- Choose clear vs. “simple”
- Content vs. chrome
- Enhanced by the cloud
- Design considerations: screen size, screen density, portrait/landscape, primary ui interaction method, keyboard
3) UI framework features you should definitely be using
-
- Resource qualifiers: ie res/layout, res/layout-port, res/layout-land, res/layout-large-port, res/layout-large-land
- patch drawables
4) New UI design patterns
- introduced in last google i/o talks
- dashboard, action bar, quick actions
5) Icons
- http://j.mp/androidfun for some icon ideas
Official Twitter app was developed by Google. Will be open sourced. No timeline on this.
The Google I/O conference app is still available in the app store. Source is available at: http://code.google.com/p/iosched
Developing REST client apps
1 min. intro to REST
Native REST Client vs. Mobile Web App
- Deep system integration (ie, contacts, sync UI)
- Can run in the backgroud, sync on a schedule
- Potential faster – binary formats
- Some things aren't yet possible with HTML/JS (eg, taking a photo)
Implementing REST
- do data operations in a service, not an activity
Thress design patterns to handle
1) Service API
2) ContentProvider API
3) ContentProvider API with SyncAdapter
Intermission: Android YouTube Commercials
Why SVG isn't supported (yet):
- rather expensive from a storage perspective
- not many websites use it currently
- it might be in foryo
Porting C codebases to Android
Native Code whys:
- Existing C/C++
- HPC
- OpenGL EL 2.0 (in Android)
NDK
- c library
- math libs
- minimal c++ (stl port)
- logging in android
- zlib
- jni graphics
- new in 2.2 (ndk debugging on retail devices)
Using JNI (Java Native Interface)
- public static native void …
- plain 'old JNI can be used
Case Study: Audio Processing and Mixing
Case Study: Driving Android Display from Native Code
Showed a demo of a C (and OpenGL) version of Tetris on a Nexsus One
