Android

Michael Greifeneder

Image source: Android homepage

   

Inhalt

● Overwiew● Hardware● Software

● Development● Tools● Basics● Debugging/Emulator● Location

● Demo

   

Android And Me

● Why I like Android● Blend of Linux and Java● Open (Source)● Development on Ubuntu :)● USB mass storage● Tethering (USB, Wifi)

● Don't like● Battery life● Default LookNFeel

   

Hardware

● Typically ARM processors, up to 1 GHz● 256-512 MB RAM, up to 1 GB ROM● Connectivity: GSM/EDGE, UMTS,

Bluetooth, Wi-Fi, and WiMAX.● Cameras, GPS, accelerometers, SD card● Optional

physical keyboard● ~34 devices...

Image sources: Device manufacturer

   

3,4

28

13,8

12,3

4,73,1

Forecast 2010 North America

SymbianRIMAppleGoogleMicrosoftPalm

44,3

19,4

15,4

9,6

6,83,70,7

1Q10 Worldwide Sales

SymbianResearch In MotioniPhone OSAndroidMicrosoft Windows MobileLinuxOther OSs

Smartphone Sales Stats● North America

● Source: Canalys● Total: 65 Mio

● Worldwide 1Q10● Source: Gartner● Total: 54 Mio/Q

http://www.gartner.com/it/page.jsp?id=1372013 http://www.gartner.com/it/page.jsp?id=985912

2008 2009 2010

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Q1 Worldwide

AndroidiPhone

   

Markets● Google's Android Market (>50.000 Apps)

● 25$ one-time registration● No restrictions

● Alternatives available (android.pdassi.de)● Just click on an .apk file...

http://xkcd.com/662/ Creative Commons Attribution-NonCommercial 2.5 License.

   

Software● Tweaked Linux kernel (2.6.27-32)

● No X Window System● Dalvik/Java Runtime

● register-based architecture● .dex format● dx tool convert .class files to .dex● Neither AWT, Swing nor JavaME

supported● JIT implementation (Android 2.2)

● Open Source (Apache license)

   

Architecturehttp://developer.android.com/guide/basics/what-is-android.html

   

Kernelhttp://android.git.kernel.org/

From Kevin Mcdonagh slides: http://www.scribd.com/doc/31664622/Android-Source-Code-Guided-Tour

   

Versions

● Cupcake● 1.5 (API 3)

● Donut● 1.6 (API 4)

● Eclair● 2.0 (API 5), 2.0.1 (API 6) +2.1 (API 7)

● FroYo (Frozen Yoghurt)● 2.2 (API 8)

Image source: Android homepage

   

Development

● Android SDK● → http://developer.android.com/sdk

● Eclipse + Android Development Tools● https://dl-ssl.google.com/android/eclipse/

● Java+XML● C/C++ for NDK

Image source: Self-made screenshots

   

Toolset

● adb (Android Debug Bridge)● Installing an Application● Copying Files to or from Device/Emulator● Remote Shell

● z.B. Sqlite command-line

● DDMS (Dalvik Debug Monitor Server)● Uses adb● middleman btw. IDE + applications

● logcat

   

Emulator

● Android Virtual Devices (AVD)● hardware profile● mapping to a system image● dedicated storage area

● Emulator runs AVDs● Emulates: Calls, SMS● Location, Camera● Network-speed

Image source: Self-made screenshots

   

Widgets● Layout in XML files● Layouts: LinearLayout,

RelativeLayout, FrameLayout, TableLayout,AbsoluteLayout(pfui)

● Basic Widgets: TextView, Button, EditText, ImageView

● DatePicker, TimePicker, Tabs● OptionMenu, ContextMenu● WebView (WebKit)

Image source: Self-made screenshots

   

GUI Designer?

● Android Layout Editor in Eclipse● Forget it.

● DroidDraw http://www.droiddraw.org/● Yeah,

but...

Image source: Self-made screenshots

   

Project Structure

● AndroidManifest.xml● /src● /res

● /layout● /menu● /drawable

● /gen● /values/strings.xml

   

Security

● User must confirm access● Declare required

permissions inAndroidManifest.xml

● <uses-permission android:name= "android.permission.INTERNET"/>

● <uses-permission android:name= "android.permission. ACCESS_FINE_LOCATION" />

● <uses-permission android:name= "android.permission.CAMERA" />

Image source: http://www.taosoftware.co.jp/en/android/wakeupcallmaker/

   

Activities <--> Intents

● Activity = One screen● Intents (abstract description of an operation)

● Explicit intents (same app)● Implicit intents (inter App operation)

● Example:● Action: Intent.ACTION_DIAL● Data: ”tel:01567890”

● Intent filters● Declare receiving of intents

   

Activity

● Methods● onCreate

● setContentView(R.layout.XML_FILE);● findViewById(R.id.ID_IN_LAYOUT);

● onDestroy/onPause/onResume● Call internal activity

● Intent intent = new Intent(this, OtherActivity.class);startActivity(intent); //or startActivityForResult(intent, 1);

   

The Mighty List

● android.widget.ListView(ListActivity)

● ListAdapter for data● Indiviual layout for row● ArrayAdapter

one Textview in row● SimpleCursorAdapter

● Maps DB columns to resource ids in row layout

Image source: Self-made screenshots

   

Services...

● Use case● Background tasks● Long running tasks

● Implement a service● AndroidManiferst.xml

<service android:name=".MyService" />

● onCreate/onStart/onDestroy

● onBind() → return a subclassed Binder that extends Binder and implements custom method:

getService()

   

Use Service (local)

● Intent intent = new Intent(this. Service.class)

● bindService(intent, serviceConnection, 0);

● interface ServiceConnection {onServiceConnected(Binder binder,...)onServiceDisconnected(...)}

● ((LocalBinder) binder).getService()

   

Location aware

● LocationManager● getLastKnownLocation● Register for periodic updates● Get notified on location

● Emulator● Open console● telnet localhost <5554?>● geo fix <longitude> <latitude>

   

Demos

● DB query● Location (Change location in emulator)● Camera

● Intent: android.media.action.IMAGE_CAPTURE is buggy

● http://code.google.com/p/android/issues/detail?id=1480

● Workaround: Do it yourself● Internet

● <uses-permission android:name="android.permission.INTERNET"/>

   

Source code:http://github.com/mikegr/aLogMyNight

eBooks:http://commonsware.com/books

??? Questions/Discussion ???