Android 101Part 1. Introduction, basics,

and your environment

While we wait…

Android ADT Bundle

http://developer.android.com/sdk/index.ht

ml

Genymotion

http://www.genymotion.com/

Prerequisites

OOP Language Experience

Computer (Mac/Linux/Windows)

Plus:

Java – programming

XML – layouts and resources

Command Line – general commands

What is Android?

Platform

The operating system

Framework

Set of APIs to develop for the platform

SDK

Set of tools (including the framework) to

assist developing for the platform

Source: http://www.armdesigner.com/NewsLook617.html

Android and Google

Android is open source (AOSP)

Google is the owner/maintainer

Source: http://source.android.com

GApps

Google specific closed source apps

Google Play Store

Google Play Services

Google Maps

…

Uses for Android?

Calls

Music

Videos

Games

Social

…

Educational

Commercial (POS)

Satellite

Security

Accessory

…

Android vs iOS

Open Source

Java / XML

78.4% MS Worldwide

50.6% MS USA

$100-$200/month

800,000 apps

~$130,000 senior dev

Closed Source

Objective-C

17.6% MS Worldwide

43.9% MS USA

$500-$1000/month

800,000 apps

~$120,000 senior dev

Versions (OS vs API)

ComponentsIn context of our demo

application

Demo Application

Features:

Displays lists of saved notes

Allows user to add and edit notes

Can record notes

Can playback notes

Stops recording or playback when a call is

incoming or made

Step 1: DisplayWe need to display a few screens to the user…

Activities

Represents a single screen

extends Activity class

Fragments

Represents a section of the screen

An Activity coordinates the Fragment(s)

Fragments can be reused

extends Fragment class

Step 2: Persist DataWe need to persist the notes the user adds…

ContentProvider

Manages data

Can use almost any storage option

SQLite

File

Remote Server

…

Provides consistent interface (CRUD)

Can be restricted with permissions

extends ContentProvider class

Step 3: Record/Play

AudioWe need to record or play audio while allowing for

multitasking…

Services

Used to perform in the background

Service class works in main thread

IntentService (child class) works in

background thread

Background = No user interface

extends Service class

Step 4: Phone stateWe need to stop/pause audio playback or

recording…

BroadcastRecievers

Listens to system-wide events

Incoming SMS

Alarm

Network State

…

Usually triggers a larger action

extends BroadcastReciever class

Using the

Components

AndroidManifest.xml Declares: Permissions used

Libraries required

Hardware required

Package name (must be unique)

Application name

Components Activity <activity>

Service <service> ContentProvider <provider> BroadcastReciever <reciever>

…

Intents (options) Component Name

The name of the component to start

Action Examples: VIEW, EDIT, PICK

Data Uri to the data

Examples: Image, URL, Document

Category Examples: Browsable, Launcher

Extras Key-value pairs of data to pass to the component

Flags Used to tell the Android system how to launch certain

components

extends Intent class

IntentFilters action

name android.intent.action.SEND

com.example.whatever.DO_IT

data mimeType scheme host port path …

category BROWSABLE LAUNCHER DEFAULT

Intents Explicit Intent

Intent to start a specific component you know exists, such as from your app or a system component

new Intent(this, SecondActivity.class)

Implicit Intent

Intent to do a general action and possibly allow other applications to handle it

new Intent(Intent.ACTION_VIEW,

Uri.parse(“http://google.com”))

extends Intent class

ResourcesA very quick glimpse

Resources

animator

anim

color

drawable

layout

menu raw

values arrays

colors dimens strings styles

xml

res/ directory

Resources (qualifiers)

Language and region

Layout direction Smallest Width Available Width Available Height Screen size Screen Aspect

Screen Orientation UI Mode Screen Pixel Density Platform Version …

res/ directory

EnvironmentSetting it up

Environment - Java JDK

Java 7 JDK - http://goo.gl/zXjC

To confirm:

… run: javac –version

… output: javac 1.7.0_45

Environment - ADT Bundle

ADT Bundle - http://goo.gl/2qpr

Eclipse + ADT Plugin

Android SDK Tools

Android Platform Tools

Latest Android platform

Latest Android System image