Download Android Lecture File - e

Android Application
Development with Java
SCSR 3243 (NetCentric Computing)
2014/15-2
Mohd Soperi
[email protected]
Overview

What is Android?

Android Milestones

Android Application Development

Application Components

Hello, Android

Basic Android graphics

Part 2: More Android!
What is Android?
What is Android?



An open source Linux-based operating system,
created by Google specifically for use on mobile
computing platforms
Can be programmed in C/ C++ but most application
development is done in Java (Java access to C
Libraries via JNI (Java Native Interface))
Supports Bluetooth, Wi-Fi, 3G, 4G, … networking
Commonly Used Packages
•
•
•
•
User interface controls and widgets
User interface layout
Secure networking and web browsing
Structured storage and relational databases
(SQLite RDBMS)
• 2D and 3D Graphics SGL and OpenGL
• Audio and visual media support
• Access to optional hardware (GPS)
Android Milestones
• October 2003, Android Inc. founded
• August 2005, Google acquires Android Inc.
• 5 November 2007, Open Handset Alliance (OHA)
formed. Android unveiled
• 12 November 2007, Android Beta SDK released
Android Milestone
Android
version
1.0 G1
SDK release*
Notable updates
February 2008
• GPS and Bluetooth (but not stereo Bluetooth)
• Multitasking
• Tight integration with Google services like Gmail,
Google Maps (with Street View), and Google
Calendar
• Apps: Amazon MP3 Store; YouTube
• Android Market (about 35 apps at launch)
• No Microsoft Exchange Server; no camcorder
Android Milestone
Android
version
1.5
Cupcake
SDK release*
April 2009
Notable updates
• Universal search box (search had been limited to
the Web)
• Revamped Android Market: Browsing categories
(Apps, Games, Downloads) and filters (Top Free,
Top Paid, Just In)
• Camera: Toggle between camera and video
modes; integrated photo gallery and camera with
bulk photo deleting
• SDK expands support for gestures, voice-to-text
Android Milestone
Android
version
1.6
Donut
SDK release*
Notable updates
September 2009
• Virtual onscreen keyboard
• Camcorder mode for recording (and watching)
video
• Stereo Bluetooth
• Home screen widgets and folders
• Copy/paste and search within the browser
• Direct upload to YouTube and Picasa
Android Milestone
Android
version
2.0 Eclair
SDK release*
October 2009
Notable updates
• Multiple user accounts
• Exchange support; universal email inbox
• Quick Contact pop-up widget to launch
communications with friends in the address book
• Search saved SMS and MMS messages
• Camera improvements include support for flash
and digital zoom
• Bluetooth 2.1
• Keyboard improvements: Adaptive dictionary that
includes contact names in suggestions
Android Milestone
Android
version
2.1 Eclair
2.2
Froyo
SDK release*
January 2010
May 2010
Notable updates
• Live wallpaper; five home screens
• Speech-to-text added to any text field;
microphone icon for voice dictation in emails,
texts, and so on
• Speedier OS
• USB tethering and hotspot support
• Android Market update: Batch and automatic
updates; installing apps to the SD card
• Adobe Flash 10.1
• File uploading in the browser
• Improved Microsoft Exchange support: Security
policies, global address lookup, calendar sync,
remote wipe
• Bluetooth support for voice dialing and contact
sharing
Android Milestone
Android
version
2.3
Gingerbread
3.0
Honeycomb
SDK release*
Notable updates
December
2010
•
•
•
•
•
Redesigned copy/paste
WebM video compression support
NFC (near-field communication) support
Switch to front-facing camera from camera app
Virtual keyboard shortcuts
February 2011
•
•
•
•
•
•
•
3D graphics support
Side-by-side browser tabs; private browsing
Dual-pane modes for address book, email
Redesigned UI includes program thumbnails
Video chatting with Google Talk
Full-screen-mode photo gallery
Bluetooth tethering
Android Milestone
Android
version
3.1 – 3.2.6
Honeycomb
SDK release*
Notable updates
May 2011 –
February 2012
• Support for peripherals like keyboards and game
pads
• Resizable widgets
• "Pay as you go" support for 3G, 4G tablets
• Various bug fixes and enhancements
Android Milestone
Android
version
SDK release*
Notable updates
•
•
•
•
•
•
4.0 Ice
Cream
Sandwich
October 2011
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Support for virtual buttons in addition to touch-sensitive buttons
Create folders by dragging apps on top of each other
A new app tray tab for thumbing through widgets
Calendar app now supports pinch-to-zoom
Gmail gets new design, offline search, swiping between conversations
New Chrome browser syncs with your bookmarks, saves pages offline, supports 16
browser tabs
More keyboard error correction, inline spell check
Customizable lock screen, launcher
Recent applications icon
Roboto typeface
New swipe/delete behavior
Improved voice integration and copy and paste
Face Unlock security feature
Data Usage tracking
Hide unwanted app icons
Shut down apps that are using background data
Native camera features include zero shutter lag, continuous focus, zoom while recording,
taking a still photo while recording, panorama photos, time lapse settings, 1080p recording
Face detection in the cameraIntegrated photo editor
New gallery layout, organized by location and person
Phone app lets you swipe between favorite friends with integrated visual voice mail
Speed up and slow down voice mails
Quick message sends canned response text message when you decline a call
Android Beam, an NFC feature for exchanging information between two phones by
tapping them
Wi-Fi Direct support
Android Milestone
Android
version
4.1 Jelly
SDK release*
July 2012
Notable updates
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Faster, smoother performance with "Project Butter"
Expandable notifications with greater interaction
Voice search access by swiping up from bottom of the screen
Voice actions engine replies to some queries
Google Now
Offline dictation
Default Chrome browser
Resizable app widgets
Android Beam support for transferring larger files, like photo and
video
New filmstrip view of recent shots in the camera app
Applications update in Google Play with just the changed code
Sound search widget for music ID
Higher-resolution contact photos
Greater accessibility options
Expanded language support, especially for Arabic and Hebrew
Interface tweaks
Android Milestone
Android
version
SDK release*
Notable updates
•
•
•
4.2 – 4.3
Jelly Bean
November
2012 – October
2013
•
•
•
•
•
•
•
•
Lock screen widgets, and the ability to open the camera from
the lock screen
Quick Settings in the notification menu to toggle Wi-Fi or
Bluetooth and more
"Daydream" screensavers, which show time and other
information when the screen is locked or device is docked
Multiple user accounts on tablets only
Support for wireless display (such as Miracast)
Accessibility features, including triple-tap to magnify the entire
screen, pan and zoom with two fingers, speech output for blind
users
Unified interface layout for all devices, with system bar at the
top of the screen, and a home screen dock
More Actionable Notifications, which let you respond to the
notification without opening the app
Bluetooth Low Energy support
Location tracking with Wi-Fi -- your device can track your
location without turning on Wi-Fi
Support for 4K resolution phones
Android Milestone
Android
version
4.4 KitKat
SDK release*
October 2013
Notable updates
• Major design interface update, especially for new
Nexus devices
• Translucent status bar in the OS and in apps
• New "immersive mode" where apps can hide
navigation and status bars
• The size of the operating system shrunk so it can
run on lower-end devices with small amounts of
RAM and internal storage
• Wireless printing using Google Cloud Print
Android Milestone
Android
version
5.0 Lollipop
SDK release*
October 2014
Notable updates
• Completely redesigned UI called Material
• Notifications on the lock screen and new pop-up
alerts
• Priority mode silences less important notifications
• Multiple user accounts for both phones and
tablets
• New recent apps menu called Overview
• Guest mode
• Screen pinning
• Battery Saver mode
• Default device encryption
• Smart lock unlocks devices with Bluetooth device
or NFC tag
Distribution of Devices
Version
Codename
API
Distribution
Jelly Bean
2.2
Froyo
8
0.3%
2.3.3 2.3.7
Gingerbread
10
5.7%
4.0.3 4.0.4
Ice Cream
Sandwich
15
5.3%
4.1.x
Jelly Bean
16
15.6%
4.2.x
17
18.1%
4.3
18
5.5%
Android 4.1.1
Android 4.0+
Gingerbread
4.4
KitKat
19
39.8%
5.0
Lollipop
21
9.0%
22
0.7%
5.1
Ice cream Sandwich
http://developer.android.com/resources/dashboard/platform-versions.htm
Data Collected during a 7-day period ending on May 4, 2015
Android 2.3
Android Application Development
Eclipse IDE/
Android Studio
Android
SDK
Android
Emulator
Android
Mobile
Device
Writing Android App using Java

No public static void main() method

Closer in spirit to servlet approach


Create subclasses of some Android-supplied base
classes that define various application
components
Create some metadata to tell Android about those
subclasses
Android App Components


Activities – building block of user interface,
analogue for window or dialog in a desktop
application, or the page in a classic Web app
Services – keep running independent of any
activity for a moderate period of time (e.g.
checking for updates to RSS feed, play back
music even if the controlling activity is no lenger
operating)
Activity
FIGURE 3.2 Important callback methods of the activity life cycle.
Copyright ©2010 Lauren Darcey and Shane Conder
Android App Components


Content Providers – to make your own data
available to yourself and other applications
Broadcast Receivers – arrange application to
listen for broadcasts (e.g. battery getting low,
screen turns off, connectivity changes from WiFi to
mobile data, etc)
Widgets, Containers, Resources,
Fragments



Most activities use “widget framework” for
rendering their user interfaces, although
2D(Canvas) and 3D (OpenGL) APIs can be used
for more specialized GUIs
Widget – “micro” unit of user interface (e.g. fields,
buttons, labels, lists, etc.)
Activity’s UI is made up of one or more widgets
Activity with widgets
Widgets, Containers, Resources,
Fragments



When activity has more than one widget, the app
need to tell android how the widgets are organized
Container classes – layout managers: Put widgets
in rows, columns or more complex arrangements
Layout resource file – describes how containers
and widgets are connected. Resource refers to
images, strings, or other materials not in form of
programming language code.
Widgets, Containers, Resources,
Fragments


UI Layout – another type of resource created using
a structured tool or by hand in XML form
Fragment – supporting large screens by “snapping
together” parts of smaller screen (e.g. Gmail on a
tablet shows list of labels, list of conversations in a
selected label, and list of messages in a selected
conversation, all in one activity, but Gmail on a
phone cannot and shows labels, conversations,
and messages in separate activities).
Android Application Development
Android
Manifest
Resource
XML
Java Source
Generated
Class
Android
Libraries
Java
Compiler
.dex
File
Dalvik
VM
Apps and Packages
javac
Java code
Byte code
.java
.class
dx
Dalvik exe
classes.dex
Byte code
Other .class files
aapt
<xml>
AndroidManifest.xml
<str>
Resources
.apk
Apps and Packages



Application comes in the form of an APK file
To distribute your apps, the APK file need to be
uploaded to PlayStore
A package must: be a valid Java package name,
not exist for two applications on a device at the
same time, not uploaded to PlayStore for two
applications with same name
Android Deployment
• Apps are packaged in .apk format, variant of
.jar, then downloaded to device and installed
• .apk’s contain .dex files (bytecode), manifest
and various other files
• Manifest contains security and link info,
hardware access info, minimum OS release
info, etc.
Emulator



Shipped with android developer tools
A program running on your development machine
and behaves like an Android hardware
Used to emulate many different devices with
different devices, different screen sizes and
Android OS versions, by creating one or more
Android virtual devices, AVDs
Android Application Dev Stages




Write Java-syntax source code
Compile the source code into Java VM bytecode
using javac compiler
Translates the Java VM bytecode into Dalvik VM
bytecode, which is packaged with other files into
the apk file
Runs the apk file on android device or emulator,
bytecode executed by an instance of a Dalvik VM
Android Appl Development Process
Starting Android Studio
Configure Menu
Installing Tools
Installing tools




Android SDK Tools, Platform-tools, and latest
Build-tools
SDK Platform for all Android SDK releases you
want to code
ARM EABI v7a System Image, Intel x86 Atom
System Image, DO NOT choose Android 4.4
Documentation for Android SDK
Installing tools



Samples for SDK
Android Support Library and Android Support
Repository
Choose Google USB Driver if you are running
Windows
“Hello, Android”
Creating a New Project
Set the min SDK setting to API 8
Creating an Activity
Name the activity and title
Project tool window
(choose Android mode)
Modify UI to display a larger text
view object with different message
• Locate activity_android_sample.xml under app ->
res -> layout as below, and double click on it
User Interface Designer tool
Modifying the Apps
• Delete the TextView component from the design:
Click on the TextView object and press the Delete
key on keyboard
• In Pallete panel, locate the Widgets category.
Click and drag the Large Text object and drop it in
the center of the user interface design
Change the text currently displayed
Double click on the object