GOOGLE ANDROIDIntroduction to 10 10 nd n 20 20 22 22 re e ay ay rr r M M To To doo reed lffr Al A
What is ANDROID?Android is a software stack for mobile devices that includes an operating system, middleware and key applications.Android is based on Linux 2.6.29
Java? Really?When you first install the SDK you have to write in the Java programming language There is also a subset of libraries written in C/C++ for the system maintainance, media and SQLite DBEvery Java program has a VM. Google made DALVIK Virtual Machine for Android.COURSE CORRECTIONDalvik is not strictly a Java VM [different bytecodes – dex vs. class]
Register-based Dalvik VMThe Dalvik virtual machine is a register-based virtual machine, designed and written by Dan Bornstein with contributions from other Google engineers.It is optimized for low memory requirements, and is designed to allow multiple VM instances to run at once, relying on the underlying operating system for process isolation, memory management and threading support.
DEX format and APK Android programs are compiled into .dex (Dalvik Executable) files, which are turn zipped into a single .apk (Android Package) file on the device. .dex files can be created by automatically translating compiled applications written in the Java programming language. Eyjafjallajoekull ?? :o DALVIK is the name of a small village in Iceland Yes! It is the same country of the #@§@$%&!! unpronounceable Volcano!
Why me? Why Android?If you know Java programming you will be able to make money with AndroidAndroid was born in 2007 with the Open Handset Alliance www.openhandsetalliance.comMobile market for application developers? BABYLON THE GREAT THE MOTHER OF PROSTITUTES AND OF THE ABOMINATIONS OF THE EARTH
Creating a market Google has dreamed a market for the entire Mobile devices Just as the the standardized PC platforms Linux is the kernel and it is GPL [drivers] Android makes possible to distribute your applications in apk format freely Mobile operators often lock the handsets so applications cannot be added to them Sandboxes Dalvik isolation
The Power of the intentsNow think about the developing of an applicationYou have to imagine a world where every program is made like a web oneYou can mashup!Google Maps, Gmail or your contacts are in your handsYou can make an intent!The operating system takes care of figuring out what application has to call :)
The application model Activities Usually correspond to display screens Services Analogous to services or daemons in desktop OS Broadcast and Intent Receivers *These respond to requests for service from another application Content providers content://contacts/people* mobile mashups
Activity lifecicle Android recognizes that resources (memory and battery, for example) are limited on most mobile devices, and provides mechanisms to conserve those resources. The mechanisms are evident in the Android Activity Lifecycle.
How to startThe Eclipse IDESun’s Java Development Kit (JDK)The Android Software Developer’s Kit (SDK)The Android Developer Tool (ADT), a special Eclipse plug-in