Transcript Course Outline (after midterm)

Course Outline (after midterm)
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Introduction
Resources and Layout
Alternative Resources
Activity
Local Database (x2)
Remote Database (x2)
Introduction to Android
Outline
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Overview of the Android
Deploying application packages
Development tools
Step-by-step application development
Lab Exercise
Overview of the Android
• Linux-based OS for mobile devices
• History
– founded by Andy Rubin (2003), owned by Google
(2005), Open Handset Alliance (2007) - Open
source mobile platform
– In 2008 - release of the first phone to use Android
• HTC Dream (also known as the T-Mobile G1)
– High market share
Market Share
Android Architecture
• Android is a software stack for developing
mobile devices
Location Manager
Notification Manager
View System
View System
Dalvik Virtual Machine
• Dalvik Virtual Machine
Executing the Dalvik Executable (.dex) format
.dex format is optimized for minimal memory footprint.
Compilation
Package in .apk files to android devices
Android Versioning
• Platform version in class
– 4.4.2 KitKat (codename = 22)
– http://developer.android.com
• SDK Manager to manage version
– Each version has an API level
Development Tools
• Install Java SDK
• Install Android SDK
• IDE tools
– Android Studio
– Eclipse
• Install ADT Plug-ins (Android development tools)
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Class Library
Developer Tools
Emulator and System Images
Documentation and Sample Code
Step-by-Step
• Create HelloWorld Application
– File..New..Android Application Project
– Follow the step
• Beware of choosing target API with compile API
UI screen
• Layout file
– The XML file is translated into a View instance
• In Android, all UI elements are Views (or inherit from the
View class) – it’s kind of like JComponent in Swing.
• Activity
– Typically correspond to one UI screen
• A java class that control how UI functions
– The Activity class has a method called setContentView
which sets the layout that will be displayed in the
Activity.
Layout
• xml file that describes how to layout a set of
window components.
• e.g. chesslayout.xml
• <LinearLayout …>
• <ImageView …> </ImageView >
• <TextView …> </TextView>
• <TextView …> </TextView>
• </LinearLayout>
Structure
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src/
– Your Java files for your application go here in subdirectories.
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gen/
– Contains Java files automatically generated such as your R.java file.
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res/
– Contains app resources, such as images, layout files, string values.
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assets/ Optional
– You can use it to store other raw asset files.
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Bin/
– Results of building a project
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AndroidManifest.xml
– Describes the contents of your application.
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default.properties
– This file contains Android project settings.
Resource
• In Android, anything that is not pure code is
written in a separate resource file (not a java
file), for example strings, images, etc.
– enables easier multi-language support
Res folder
• Resource files are saved as XML
file
• The Resource Complier generates
a Java file which reference the data
in these XML files.
– called R.java
• Using this file you can access the
data in java code
– For example, R.Layout.Button1;
Images and layouts
• Resources IDs automatically generated in R.java
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chesslayout.xml
bishop.png
in res/layout
in res/drawable
• Entries in R.java magically appear.
Don’t control or care about the actual integer values.
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• gen/game/chess/R.java
public final class R {
public static final class drawable {
public static final int bishop=0x7f020002;
• Your Java code…
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setContentView(R.layout.chesslayout);
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mBishop = getDrawable(R.drawable.bishop);
4/9/2016
Hands-On-Tutorial, Loeb & Angrave 2010
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Running Emulator
• Go to Android Virtual Device Manager
– Click create and then start if finishes
AVD Manager
• An Android Virtual Device (AVD) is an emulator
configuration that lets you model an actual device by
defining hardware and software options to be
emulated by the Android Emulator.
• Select Window > Android Virtual Device Manager, or
click the AVD Manager icon in the toolbar
• Emulator Command
http://developer.android.com/tools/help/emulator.ht
ml
Accessing layout elements from
Activity
Use findViewById
R.id.name corresponds to
the name given in the xml
file
Event Listener