Android overview

June 21, 2017 www.snipe.co.in 1

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Android Overview

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Agenda
•Android Overview
- what is android
- Features of Android
- Why Android?
- Android History
• Platform
- Hardware
-operating system
-network connectivity
-security
-performance
• Development environment
- java
- android sdk
- eclipse
- IDE & Tools
-software
-Emulators

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Android Overview
• What is Android ?
•Android is software stack for mobile devices that includes an
operating system, middleware and key applications.
• Built on Linux kernel
• Developed by Google and later the Open Handset Alliance(OHA)
• Allows writing managed code in Java Language

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Android Overview
• Features of Android ?
• Application framework enabling reuse and replacement of components
• Dalvik virtual machine optimized for mobile devices.
• Integrated browser based on the open source WebKit engine
• Optimized graphics powered by a custom 2D graphics library; 3D graphics based
on the OpenGL ES 1.0 specification (hardware acceleration optional)
• SQLite for structured data storage
• Media support for common audio, video, and still image formats (MPEG4, H.264,
MP3, AAC, AMR, JPG, PNG, GIF)

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Android Overview
• Features of Android ?
•Media support for common audio, video, and still image formats (MPEG4,
H.264, MP3, AAC, AMR, JPG, PNG, GIF)
• GSM Telephony (hardware dependent)
• Bluetooth, EDGE, 3G, and WiFi (hardware dependent)
•Camera, GPS, compass, and accelerometer (hardware dependent)
• Rich development environment including a device emulator, tools for
debugging, memory and performance profiling, and a plugin for the Eclipse
IDE

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Android Overview
• Why Android ?
•The OHA is committed to make their vision a reality: to deploy the
Android platform for every mobile operator, handset manufacturers and
developers to build innovative devices
• Google Android Sales to Overtake iPhone in 2012
• Engineering expertise to help run Android on embedded hardware, which
aside from cellphones, mobile internet devices, and portable media players,
could include GPS devices, thin-client computers and set-top boxes.
• The ability for anyone to customize the Google Android platform

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Android Overview
• Android History?
• 2005
Google acquires startup Android Inc. to start Android platform
Work on Dalvik VM begins
• 2007
Open Handset Alliance announced
Early look at SDK
• 2008
Google sponsors 1st Android Developer Challenge
T-Mobile G1 announced
SDK 1.0 released
Android released open source (Apache License)
Android Dev Phone 1 released

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Android Overview
• History ..
•2009
•SDK 1.5 (Cupcake)
•New soft keyboard with “autocomplete” feature
•SDK 1.6 (Donut)
•Support Wide VGA
•SDK 2.0/2.0.1/2.1 (Eclair)
•Revamped UI, browser
•2010
•Nexus One released to the public
•SDK 2.2 (Froyo)
•Flash support, tethering
•SDK 2.3 (Gingerbread)
•UI update, system-wide copy-paste

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Android Overview
• Android History ..
•2011
•SDK 3.0 (Honeycomb) for tablets only
•New UI for tablets, support multi-core processors
•SDK 3.1 and 3.2
•Hardware support and UI improvements
•SDK 4.0 (Ice Cream Sandwich)
•For Q4, combination of Gingerbread and Honeycomb

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Android Overview
•

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Android Platform
• Hardware
• Android is not a single piece of hardware; it's a complete, end-to-
end software platform that can be adapted to work on any number of
hardware configurations. Everything is there, from the bootloader all
the way up to the applications

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Android Platform
• Operating System ?
• Android uses Linux for its device drivers, memory management,
process management, and networking.
• The next level up contains the Android native libraries. They are all
written in C/C++ internally, but you’ll be calling them through Java
interfaces. In this layer you can find the Surface Manager, 2D and
3D graphics, Media codecs, the SQL database (SQLite), and a native
web browser engine (WebKit).
• Dalvik Virtual Machine. Dalvik runs dex files, which are converted at
compile time from standard class and jar files.

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Android Platform
• Network Connectivity
It supports wireless communications using:
 GSM mobile-phone technology
 3G
 Edge
 802.11 Wi-Fi networks

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Android Platform
• Security
• Android is a multi-process system, in which each application (and
parts of the system) runs in its own process.
• Most security between applications and the system is enforced at
the process level through standard Linux facilities, such as user and
group IDs that are assigned to applications.
• Additional finer-grained security features are provided through a
"permission" mechanism that enforces restrictions on the specific
operations that a particular process can perform, and per-URI
permissions for granting ad-hoc access to specific pieces of data.

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Android Platform
• Performance

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Development Environment
• Development Requirements
• Java.
• Android SDK.
• Eclipse IDE (optional)
• Emulators

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• IDE & Tools
• Android SDK.
• Class Library
• Developer Tools
 dx – Dalvik Cross-Assembler
 aapt – Android Asset Packaging Tool
 adb – Android Debug Bridge
 ddms – Dalvik Debug Monitor Service
• Emulator and System Images
• Documentation and Sample Code
• Eclipse IDE + ADT (Android Development Tools)
• Reduces Development and Testing Time
• Makes User Interface-Creation easier
• Makes Application Description Easier

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• Emulators or AVD
•Emulator is essential to testing app but is not a substitute for a real
device
•Emulators are called Android Virtual Devices (AVDs)
•Android SDK and AVD Manager allows you to create AVDs that
target any Android API level
•AVD have configurable resolutions, RAM, SD cards, skins, and other
hardware

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• Emulators or AVD :1.6 Device

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• Emulators or AVD : 2.2 Device

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• Emulators or AVD : 3.0 Device
•

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• Emulators Basics
•Host computer’s keyboard works
•Host’s mouse works like finger
•Uses host’s Internet connection
•Side buttons work: Home, Menu, Back, Search, volume up and down, etc.
•
•Ctrl-F11 toggle landscape  portrait
•Alt-Enter toggle full-screen mode
•More info at
http://developer.android.com/guide/developing/devices/emulator.html

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• Emulators Limitations:
•No support for placing or receiving actual phone calls
•Simulate phone calls (placed and received) through the emulator console
•No support for USB connections
•No support for camera/video capture (input)
•No support for device-attached headphones
•No support for determining connected state
•No support for determining battery charge level and AC charging state
•No support for determining SD card insert/eject
•No support for Bluetooth
•

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• Programming Languages
• Java Officially Supported
• C/C++ also possible but not Supported

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Android Architecture

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Agenda
•Architecture
- Applications
- Application Frameworks
- Libraries & Android Runtime
- Linux Kernel

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• Major Components

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• Applications
• Android will ship with a set of core applications including an email
client, SMS program, calendar, maps, browser, contacts, and others.
• All applications are written using the Java programming language.

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• Application Frameworks
• By providing an open development platform, Android offers developers the ability
to build extremely rich and innovative applications.
• Developers are free to take advantage of the device hardware, access location
information, run background services, set alarms, add notifications to the status bar,
and much, much more.
• Developers have full access to the same framework APIs used by the core
applications.
• The application architecture is designed to simplify the reuse of components; any
application can publish its capabilities and any other application may then make use of
those capabilities (subject to security constraints enforced by the framework).

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• Application Frameworks
• A rich and extensible set of Views that can be used to build an application,
including lists, grids, text boxes, buttons, and even an embeddable web browser
• Content Providers that enable applications to access data from other applications
(such as Contacts), or to share their own data
• A Resource Manager, providing access to non-code resources such as localized
strings, graphics, and layout files
• A Notification Manager that enables all applications to display custom alerts in the
status bar
• An Activity Manager that manages the lifecycle of applications and provides a
common navigation backstack

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• Libraries
• Android includes a set of C/C++ libraries used by various components of the
Android system. These capabilities are exposed to developers through the
Android application framework. Some of the core libraries are listed below:
• System C library - a BSD-derived implementation of the standard C system
library (libc), tuned for embedded Linux-based devices
• Media Libraries - based on PacketVideo's OpenCORE; the libraries support
playback and recording of many popular audio and video formats, as well as
static image files, including MPEG4, H.264, MP3, AAC, AMR, JPG, and PNG
• Surface Manager - manages access to the display subsystem and seamlessly
composites 2D and 3D graphic layers from multiple applications

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• Libraries
• LibWebCore - a modern web browser engine which powers both the Android
browser and an embeddable web view
• SGL - the underlying 2D graphics engine
• 3D libraries - an implementation based on OpenGL ES 1.0 APIs; the libraries
use either hardware 3D acceleration (where available) or the included, highly
optimized 3D software rasterizer
• FreeType - bitmap and vector font rendering
• SQLite - a powerful and lightweight relational database engine available to all
applications

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• Android Runtime
• Android includes a set of core libraries that provides most of the functionality
available in the core libraries of the Java programming language.
• Every Android application runs in its own process, with its own instance of the
Dalvik virtual machine.
• Dalvik has been written so that a device can run multiple VMs efficiently. The
Dalvik VM executes files in the Dalvik Executable (.dex) format which is optimized
for minimal memory footprint.
• The VM is register-based, and runs classes compiled by a Java language compiler
that have been transformed into the .dex format by the included "dx" tool.
• The Dalvik VM relies on the Linux kernel for underlying functionality such as
threading and low-level memory management

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• Linux Kernel
• Android relies on Linux version 2.6 for core system services such as security,
memory management, process management, network stack, and driver model. The
kernel also acts as an abstraction layer.
• performs security
• Memory management
• Process Management
• Power management
• Hardware drivers

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Installation & Configuration

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Agenda
• Installation & Configuration
- Setup Development Environment
- Overview of Tools
- Debugging
- Simple Example to test

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• Setup Development tools
• The best way to develop applications for Android is using the
Eclipse IDE and the Android plug-in for Eclipse called Android
Development Tools (ADT). The plug-in allows you to run your
applications on an Android Virtual Device (AVD), aka Android
emulator.
http://www.slideshare.net/magicshui/android-installation-guide Kindly
follow this url and prepare this installation guide as follows.

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• Installation Steps
• Install & Configure Java
• Download & Configure Eclipse
• Install ADT Plugin for eclipse
• How to develop simple project and Run the application
• How to debug

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Install & Configure Java
• Installing JDK on Windows
• For the version of the JDK, download latest version from the URL
http://www.oracle.com/technetwork/java/archive-139210.html
• Select Download J2SE SDK. ( e.g. jdk is 6 update 1 )
• Select and download Windows Installation, Multi-language.
• Save and install the .exe file.
• If prompted, install the JDK to C Drive

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• For the version of the JDK, download latest version from the URL
http://www.oracle.com/technetwork/java/archive-139210.html
• Select Download J2SE SDK. ( e.g. jdk is 6 update 1 )
• Select and download Windows Installation, Multi-language.
• Save and install the .exe file.
• If prompted, install the JDK to C Drive

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• Now a "License Agreement" window opens. Just read the agreement
and click "Accept" button to accept and go further.

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• Now a "Custom Setup" window opens.

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• Click on "Change" button to choose the installation directory. Here
it is "C:Program Files Javajdk1.6.0_01". Now click on "OK”

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• Clicking the "OK" button starts the installation. It is shown in the
following figure.

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• Next window asks to install Runtime Environment.

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• Click the "Change" button to choose the installation directory of
Runtime Environment. We prefer not to change it. So click "OK“

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• Click "OK" button starts the installation. Click "Finish" after
installation.

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• The above installation will create two folders "jdk1.6.0_01" and
"jre1.6.0_01" in "C: Program Files java" folder.

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• To make available Java Compiler and Runtime Environment for
compiling and running java programs, set the system environment
variables.

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• Now set the JAVA_HOME variable and set its value to "
C:Program FilesJavajdk1.6.0_01 ".

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• Now this is the final step to check that you have installed jdk
successfully and it is working fine. Just go to the command prompt
and type javac and hit enter key you will get the help screen on
command prompt.

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Download & Configure Eclipse
• Setup Android SDK With Eclipse
• Operating Systems support for Android SDK
• Windows XP (32-bit), Vista (32- or 64-bit), or Windows 7 (32- or 64-
bit)
• Mac OS X 10.5.8 or later (x86 only)
• Linux (tested on Ubuntu Linux, Lucid Lynx). GNU C Library (glibc) 2.7
or later is required. On Ubuntu Linux, version 8.04 or later is required.
64-bit distributions must be capable of running 32-bit applications.
• Eclipse IDE support
• Eclipse 3.4 (Ganymede) or greater.
• Eclipse JDT plugin (included in most Eclipse IDE packages)

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• Setup Android SDK With Eclipse
• download Android SDK for your system from
http://developer.android.com/sdk/index.html
• Windows : installer_r16-windows.exe or android-sdk_r16-windows.zip.
• Mac OS (intel) : android-sdk_r16-mac_x86.zip
• Linux (i386) : android-sdk_r16-linux_x86.tgz
• Need latest version of JDK to be able to use Android SDK with
Eclipse. We already seen in previous slides.

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• Installing Android SDK
• Since we use Windows I present here how it works in Windows. but
it should be almost similar in other Operating Systems.
• The Android SDK we have just downloaded is not the complete
software required to begin the development. It is just the core SDK
tool which can be used to download the rest of the SDK components.
• When you click the '.exe' installer windows will ask you if you want
to save the file or cancel download as seen in the figure below. Select
Save File and wait for the file to download.

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• After the file has downloaded run the setup file. You will be shown
the welcome screen. Press Next on this screen.

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• If JDK is not found on your system you will be asked to download it
from the Java website. Click on Visit java.oracle.com to install the
JDK. Without the JDK you cannot continue with the installation. If
you already have JDK installed you can proceed next Step.

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• After Installing the JDK you can press the Back button and then
click Next button on the Android SDK installer. Now you will see that
the previously disabled 'Next' button is enabled. Click the Next
button to proceed forward.
• We will now be asked to choose the directory where you want to
install Android SDK tools. Remember the name and location of the
SDK directory on your system as you will need to refer to the SDK
directory later, when setting up the ADT plugin and when using the
SDK tools from command line. In this article we use the default SDK
location C:Program FilesAndroidandroid-sdk.

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After choosing the location where the SDK will be installed press Next.

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• Next you will be asked to Choose if you want to make a Start Menu
Folder. If you do not want to make a Start Menu Folder select the
box Do not create shortcuts. If you want to create Start Menu
Folder than just click Install.

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• Installing the ADT Plugin for Eclipse
• As stated on the Android's Developer website "Android offers a
custom plugin for the Eclipse IDE, called Android Development Tools
(ADT), that is designed to give you a powerful, integrated
environment in which to build Android applications. It extends the
capabilites of Eclipse to let you quickly set up new Android projects,
create an application UI, debug your applications using the Android
SDK tools, and even export signed (or unsigned) APKs in order to
distribute your application. In general, developing in Eclipse with ADT
is a highly recommended approach and is the fastest way to get
started with Android."

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• Follow the steps below to install the ADT plugin in
Eclipse:
• Eclipse must be installed on your system to proceed further from
here.
• Eclipse 3.6 (Helios). Start Eclipse and then select Help > Install
New Software

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• Steps below to install the ADT plugin in Eclipse:
• Click Add, on the top right corner. A small Add Repository Dialog
appears. In this Dialog enter "ADT Plugin" for the Name and the URL
for the Location: https://dl-ssl.google.com/android/eclipse/

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• Next you will be back in the Available Software dialog. In this dialog
select the checkbox next to Developer Tools and click Next.

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• Eclipse will look for dependencies and then show you the next
window. Here you can see a list of the tools to be downloaded. Click
Next.

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• Next you will be shown the license agreements. Read and accept the
license agreements, then click Finish.
• After the installation finishes, restart Eclipse.

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• Configuring the ADT Plugin
• Till now we have been able to Install Android SDK tools and ADT
for Eclipse. The next step is to modify the ADT preferences in
Eclipse to point to the Android SDK. We follow the following steps to
do this task:

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• Start Eclipse. Select Window > Preferences... to open the
Preferences panel.

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• In the left panel you can see Android. Select Android. You can now
click Browse... to locate the folder where you have downloaded the
Android SDK. Select the folder which contains the tools folder.
• Now you are all done to move to the final step before you can start
development for Android SDK. Click Apply, then OK.

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• Adding Platforms and Other Components
• This is the last step before you can start developing your apps for
Android SDK. In this step we will see how to use Android SDK and
AVD Manager to download the important SDK components for the
development environment. The steps involved are,
• Start Eclipse, select Window > Android SDK and AVD Manager or
we can go to the root directory ('C:Program FilesAndroidandroid-
sdk') where we have installed the Android SDK and double-click the
'SDK Manager.exe' file.

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• Adding Platforms and Other Components

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Application Development

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Agenda
• Application Fundamental
• Key-concepts of Android
- Android Project Structure
- Activities
- Services
- Broadcast Receiver
- Content Provider
- Intents

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Android Fundamental
• Android Fundamental
• Android applications are composed of one or more application components (activities,
services, content providers, and broadcast receivers)
• Each component performs a different role in the overall application behavior, and each
one can be activated individually (even by other applications)
•The manifest file must declare all components in the application and should also declare
all application requirements, such as the minimum version of Android required and any
hardware configurations required
•Non-code application resources (images, strings, layout files, etc.) should include
alternatives for different device configurations (such as different strings for different
languages and different layouts for different screen sizes)

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Android Fundamental
• Android applications are written in the Java programming language.
• The Android SDK tools compile the code—along with any data and resource
files—into an Android package, an archive file with an .apk suffix.
• All the code in a single .apk file is considered to be one application and is the
file that Android-powered devices use to install the application
• Once installed on a device, each Android application lives in its own security
sandbox
• The Android operating system is a multi-user Linux system in which each
application is a different user.

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Android Fundamental
• By default, the system assigns each application a unique Linux user
ID (the ID is used only by the system and is unknown to the
application).
• The system sets permissions for all the files in an application so
that only the user ID assigned to that application can access them.
• Each process has its own virtual machine (VM), so an application's
code runs in isolation from other applications.

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Android Fundamental
Java
code
Byte
code
Dalvik
exe
Byte
code <xml>
<str
>
.java .class
Other .class files
javac
dx
classes.dex
AndroidManifest.xml
Resources
.apk
aapt

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Key-Concepts of Android
• Project Structure : Step to create android project

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Key-Conceps of Android
• Project Structure : Step to provide details

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Key-Conceps of Android
• Project Structure : created project structure

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• Project Structure
- When project is created, there are 8 key elements of project
structure are created as follows.
-AndroidManifest.xml
- build.xml
- bin/
- libs
- src/
- res
- assets
- gen

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• AndroidManifest.xml
- Declares all the app’s components
- Names of app libraries needs to be linked
- Identifies the permission of the app aspects to be granted

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•build.xml
It is an ANT script for compiling the application and installing on the device.
BIN /:
-When you compile your project (via ant or the IDE), the results go into the
bin/ directory under your project root. bin/classes/ holds the compiled Java classes
- Bin/classes.dex holds the executable created from those compiled Java
classes
- bin/nameapp.ap_ holds your application’s resources, packaged as a ZIP file

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• BIN /:
- bin/namedebug.apk or bin/nameapp-unsigned.apk is the actual
Android application (where nameap is the name of your application)
- The .apk file is a ZIP archive containing the .dex file, the
compiled edition of your resources, any un-compiled resources (such as
what you put in and the AndroidManifest.xml file. )
SRC/:
-It contains all source code file (.java file) of android application.
E.g hello_world.java

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• RES /:
- Resources are to store all external contents that used in android
applications.
These are external elements that you want to include and reference within your
application, like images, audio, video, text strings, layouts, themes, etc.It contains all
resources that are used in android application
Root directory:
- res/drawable : its contain images ,pictures (png, jpeg etc) e.g. .icon.png
- res/layout : contains XML(User Interface) that UI layout used in Project
or view window of an application.(E.g. main.xml)
- res/Values : it declare Arrays, colors, dimensions, strings, and styles.(E.g.
strings.xml)
-res/raw : it contains non-complied file (e.g. Audio file .mp3, video file .mpg)

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• RES /:
-
Declares layouts & widgets for the activity
86Tree from: http://developer.android.com/guide/topics/ui/index.html

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• ASSETS:
- Assets it also store an external content refer in android
applications. Just like images, audio, video, text strings .It same as
resources but different in assets directory will maintain its raw file
format and, in order to read it, you must use the AssetManager to read
the file as a stream of bytes. So keeping files and data in resources
(res/) makes them easily accessible.
LIBS/:
- It’s holds any third-party Java JARs your application Requires

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• GEN:
- create an application that time auto generated R.java file in gen
directory. The R.java file is an index (id) into all the resources defined in
the file. This class files use in source code file or it gives for reference
or location user interface object that uses in sources code

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•

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Key concepts of Android
•ACTIVITY
•It is an application component that provides a screen with which user can interact to do
something.
e.g:- view a map, send email and enter the form fields is an activities.
• The system sets permissions for all the files in an application so that only the user ID assigned
to that application can access them.
•Each process has its own virtual machine (VM), so an application's code runs in isolation from
other applications.
•Each Activity is given a window in which to draw its user interfaces.
•Presents a visual UI for a single endeavor
•Single app may be composed of several activities
Examples: list of photos, buttons to start/stop a song

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• Life Cycle of Activity
• It is a class in which derived as subclass of Activity class.
• it must implement callback methods in which activity transition
between various states its life cycle i.e. when
created/stopped/resume and destroyed.

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• Declaring Activity in Manifest
• You must declare your activity in the manifest file in order for it to be accessible to
the system. To declare your activity, open your manifest file and add an <activity>
element as a child of the <application> element.
For example: AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.compname.modulename.sample"
android:versionCode="1“ android:versionName="1.0">
<uses-sdk android:minSdkVersion="8" />
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".SampleActivity“ android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

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• Using Intent Filter
An <activity> element can also specify various intent filters—using the
<intent-filter> element—in order to declare how other application
components may activate it.
When you create a new application using the Android SDK tools, the stub
activity that's created for you automatically includes an intent filter that
declares the activity responds to the "main" action and should be placed
in the "launcher" category. The intent filter looks like this:
<activity android:name=".ExampleActivity"
android:icon="@drawable/app_icon">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

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• Service
-A service is a component that runs in the background to perform
long-running operations or to perform work for remote processes.
- A service does not provide a user interface.
- A service is implemented as a subclass of Service.
- examples
Network downloads,
Playing music,
TCP/UDP Servers

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•Service
- Service can be two forms
Started
A service is "started" when an application component (such as an activity) starts it by calling
startService().
Once started, a service can run in the background indefinitely, even if the component that started it
is destroyed.
Usually, a started service performs a single operation and does not return a result to the caller.
For example, it might download or upload a file over the network. When the operation is done,
the service should stop itself.
Bound
A service is "bound" when an application component binds to it by calling bindService().
A bound service offers a client-server interface that allows components to interact with the service,
send requests, get results, and even do so across processes with interprocess communication (IPC).

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• Service
A bound service runs only as long as another application component is
bound to it. Multiple components can bind to the service at once, but
when all of them unbind, the service is destroyed.

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•Content Provider
• A content provider manages a shared set of application data. Makes some of the
application data available to other application.
• You can store the data in the file system, an SQLite database, on the web, or any other
persistent storage location your application can access.
• A content provider is implemented as a subclass of ContentProvider and must implement a
standard set of APIs that enable other applications to perform transactions.
• it is the only way to transfer data between applications(no shared memory/pipes/shared
files so on).

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•Broadcast Receivers
• A broadcast receiver is a component that responds to system-wide broadcast
announcements.
• Many broadcasts originate from the system—
for example, a broadcast announcing that the screen has turned off, the battery is
low, or a picture was captured.
Applications can also initiate broadcasts—for example, to let other applications know that
some data has been downloaded to the device and is available for them to use. Although
broadcast receivers don't display a user interface, they may
create a status bar notification to alert the user when a broadcast event occurs.
A broadcast receiver is implemented as a subclass of BroadcastReceiver and each
broadcast is delivered as an Intent object.

June 21, 2017 101
• Intents
• Three of the core components of an application — activities, services,
and broadcast receivers — are activated through messages, called
intents.
• Intent messaging is a facility for late run-time binding between
components in the same or different applications.
• The intent itself, an Intent object, is a passive data structure holding
an abstract description of an operation to be performed

June 21, 2017 102
•Intents
• There are separate mechanisms for delivering intents to each type of component
• An Intent object is passed to Context.startActivity() or Activity.startActivityForResult() to
launch an activity or get an existing activity to do something new. (It can also be passed to
Activity.setResult() to return information to the activity that called
startActivityForResult().)
• An Intent object is passed to Context.startService() to initiate a service or deliver new
instructions to an ongoing service. Similarly, an intent can be passed to Context.bindService()
to establish a connection between the calling component and a target service. It can
optionally initiate the service if it's not already running.
• Intent objects passed to any of the broadcast methods (such as Context.sendBroadcast(),
Context.sendOrderedBroadcast(), or Context.sendStickyBroadcast()) are delivered to all
interested broadcast receivers. Many kinds of broadcasts originate in system code.

June 21, 2017 103
Application Development

June 21, 2017 104
Agenda
Sample Programming
- Hello world Example
- Activity
- 4 ways of Event Handling
- Intents
- Content Provider
- Services

June 21, 2017 105
Hello world Example

June 21, 2017 106
Activity Example
Java code – HelloWorldTest

June 21, 2017 107
main.xml
(Contd..)

June 21, 2017 108
resource bundle – strings.xml & manifestfile
(Contd..)

June 21, 2017 110
Activity Life Cycle Example
Java code – LifeCycleActivity

June 21, 2017 111
(Contd..)
main.xml

June 21, 2017 112
(Contd..)

June 21, 2017 115
4 Ways of Event Handling
Java code – EventHandlingDemoActivity

June 21, 2017 117
main.xml
(Contd..)

June 21, 2017 119
(Contd..)

June 21, 2017 121
Intents
Java code – Form Navigation Demo

June 21, 2017 123
(Contd..)

June 21, 2017 124
(Contd..)
main.xml

June 21, 2017 126
(Contd..)
result.xml

June 21, 2017 128
Content Provider
Java code – Form Navigation SQLite Activity

June 21, 2017 131
(Contd..)
resource bundle – strings.xml & manifestfileresource bundle – strings.xml & manifestfile

June 21, 2017 132
(Contd..)
display.xml

June 21, 2017 134
Services
Java code – Music Service

June 21, 2017 135
(Contd..)
Java code – Service Demo Activity

June 21, 2017 136
(Contd..)

June 21, 2017 137
(Contd..)
main.xml

June 21, 2017 138
(Contd..)
Click Start Service Button – Music Plays on

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