In dieser Session werfen wir einen Blick auf die Android Platform jenseits der Dalvik VM. Wir entdecken den Android Source Code und erklären wo sich interessante Beispiele und Referenzen für App-Entwickler sowie nützliche Tools verbergen. Ein High-Level Überblick über die Platform-Architektur und das Platform-Build-System runden die Session ab.

1. Dominik Helleberg | inovex GmbH
Core Android

2. Dominik Helleberg
Mobile Development
Android
HTML5
http://dominik-helleberg.de/+

3. Core
Android

4. Warum?
Neugier
Verständnis
- Bugs
- Beispiele
- Doku
Anwendungen / Projekte
http://www.ouya.tv/about/
https://mediacenter.motorola.com/Image-Gallery/MOTOACTV-Golf-Edition-8c1.aspx
http://www.tolino.de
https://www.honeywellaidc.com/en-US/resources/image-library/Pages/default.aspx?
Category=7800&keywords=7800&title=7800&description=7800

5. Android is different…

6. Android is open?
https://twitter.com/Arubin/status/27808662429

7. Android Architektur
Stock Apps User Apps
Framework / API
Java
System Services
Dalvik / Runtime / Zygote
Libs HAL Init
Kernel

8. Android Architektur / Source
https://android.googlesource.com/
Stock Apps User Apps
Framework / API
Java
System Services
Dalvik / Runtime / Zygote
Libs HAL Init
Kernel

9. Get the source!
$ curl https://dl-ssl.google.com/dl/googlesource/git-repo/repo > ~/bin/repo
$ chmod a+x ~/bin/repo
$ repo init -u https://android.googlesource.com/platform/manifest
$ repo sync
Check: http://source.android.com
Sources: approx. 16 GB

10. Getting around AOSP
abi docs packages
bionic external pdk
bootable frameworks prebuilts
build gdk sdk
cts hardware system
dalvik libcore tools
development libnativehelper
device ndk

11. Getting around AOSP
Stock Apps
abi docs
IMEs packages
Wallpapers..
bionic external pdk
bootable frameworks prebuilts
android core
build
Framework gdk sdk
icons
cts hardware system
dalvik libcore tools
The....
development libnativehelper S D K
device ndk

12. packages
Calendar
Contacts
Gallery2
Launcher2

13. Framework
base/core/java/android/app/ActivityManager.java
base/core/java/android/widget/RelativeLayout.java
base/packages/SystemUI/res/*
base/core/res/res/*
base/core/java/android/os/PowerManager.java

14. sdk
bash_completion/adb.bash
screenshot/

15. Compile...
You need:
• Ubuntu LTS (10.04) or Mac OS X
• A bunch of tools
• HDD space (~ 30 GB)
• Time (Hours - depending on your HW)

16. Compile...
$ source build/envsetup.sh
including device/generic/armv7-a-neon/vendorsetup.sh
including device/generic/armv7-a/vendorsetup.sh
....

17. Compile...
$ lunch
You're building on Linux
Lunch menu... pick a combo:
1. full-eng
2. full_x86-eng
3. vbox_x86-eng
4. full_mips-eng
5. full_grouper-userdebug
...
Which would you like? [full-eng]

18. zzzzzZZZZZZzzzzzz

19. device mappings
crespo Samsung Nexus S
manta Samsung Nexus 10
mako LG Nexus 4
grouper / tilapia Asus Nexus 7
toro / maguro Samsung Galaxy Nexus
wingray Motorola Xoom

20. …zzZZZzz… and run!
$ emulator &

21. …zzZZZzz… and run!

22. Architecture by example - GPS
Stock Apps User Apps
Framework / API
Java
System Services
Dalvik / Runtime / Zygote
Libs HAL Init
Kernel

23. Architecture by example - GPS
Stock Apps User Apps
locationManager = (LocationManager)
this.getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, 0, 0,
locationListener);

24. Architecture by example - GPS
frameworks/base/location/java/android/location/
LocationManager.java
Framework / API System Services
try {
mService.requestLocationUpdates(request,
transport, intent, packageName);
} catch (RemoteException e) {
Log.e(TAG, "RemoteException", e);
}

25. Architecture by example - GPS
frameworks/base/location/java/android/location/
LocationManager.java
Framework / API System Services
private final ILocationManager mService;

26. Architecture by example - GPS
frameworks/base/location/java/android/location/
ILocationListener.aidl
Framework / API System Services
void requestLocationUpdates(
in LocationRequest request,
in ILocationListener listener,
in PendingIntent intent,
String packageName);

27. Architecture by example - GPS
frameworks/base/services/java/com/android/server/
LocationManagerService.java
Framework / API System Services
LocationProviderInterface provider =
mProvidersByName.get(name);
...
provider.setRequest(providerRequest,
worksource);

28. Architecture by example - GPS
frameworks/base/services/java/com/android/server/
location/GpsLocationProvider.java
Framework / API System Services
private native boolean native_start();

29. Architecture by example - GPS
hardware/libhardware/include/hardware/gps.h
/** Represents the standard GPS interface. */
typedef struct {
int (*init)( GpsCallbacks* callbacks );
/** Starts navigating. */
int (*start)( void );
...
Libs HAL Init

30. Architecture by example - GPS
development/tools/emulator/system/gps/
gps_qemu.c
device/samsung/manta/gps/gps.exynos5.so
Libs HAL Init

31. What’s next? Tips + Tricks
• Level 1:
Check source for samples and understanding
• Level 2:
Compile your own emulator images
• Level 3:
Get a supported nexus device and burn images
• Level 4:
Get a development board an build android
embedded Software

32. Level 1: grep
$ jgrep LocationManager
./base/core/java/android/app/ContextImpl.java:60:import android.location.ILocationManager;
./base/core/java/android/app/ContextImpl.java:61:import android.location.LocationManager;
./base/core/java/android/app/ContextImpl.java:403: return new LocationManager(ctx, ILocationManager.Stub.asInterfa
./base/core/java/android/content/Context.java:1749: * <dd> A {@link android.location.LocationManager} for controlling location
./base/core/java/android/content/Context.java:1795: * @see android.location.LocationManager
./base/core/java/android/content/Context.java:1912: * android.location.LocationManager} for controlling location
./base/core/java/android/content/Context.java:1916: * @see android.location.LocationManager
./base/core/java/android/provider/Settings.java:3096: * LocationManager service for testing purposes during application deve
./base/core/java/android/webkit/GeolocationService.java:23:import android.location.LocationManager;
./base/core/java/android/webkit/GeolocationService.java:39: private LocationManager mLocationManager;
./base/core/java/android/webkit/GeolocationService.java:54: mLocationManager = (LocationManager) context.getSystemServ
./base/core/java/android/webkit/GeolocationService.java:55: if (mLocationManager == null) {
./base/core/java/android/webkit/GeolocationService.java:118: if (LocationManager.NETWORK_PROVIDER.equal
....

33. Level 1: AndroidXRef
http://androidxref.com/

34. Level 1: explain-plz
@local:/Volumes/android/dalvik $ explain-plz
Explanation for folder dalvik:
This directory contains the Dalvik virtual machine and core class library,
as well as related tools, libraries, and tests.
Git project directory: dalvik
Git fetch URL: https://android.googlesource.com/platform/dalvik
Subfolders with explanation:
dexdump
dexgen
dx
opcode-gen
tools/hprof-conv
vm
https://github.com/timroes/explain-plz

35. Level 2: ccache
$ export USE_CCACHE=1
$ export CCACHE_DIR=/<path_of_your_choice>/.ccache
$ prebuilts/misc/linux-x86/ccache/ccache -M 50G
The suggested cache size is 50-100G.
You can watch ccache being used by doing the following:
$ watch -n1 -d prebuilts/misc/linux-x86/ccache/ccache -s
http://source.android.com/source/building.html

36. Level 3

37. Level 4
https://android-build.linaro.org/

38. Credits
http://www.ouya.tv/about/
https://mediacenter.motorola.com/Image-Gallery/MOTOACTV-Golf-Edition-8c1.aspx
http://www.tolino.de
https://www.honeywellaidc.com/en-US/resources/image-library/Pages/default.aspx?
Category=7800&keywords=7800&title=7800&description=7800
https://android-build.linaro.org/
http://source.android.com/source/building.html

39. DANKE!