• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Google Android
 

Google Android

on

  • 727 views

 

Statistics

Views

Total Views
727
Views on SlideShare
726
Embed Views
1

Actions

Likes
0
Downloads
16
Comments
0

1 Embed 1

http://www.slideshare.net 1

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Google Android Google Android Presentation Transcript

    • Google Android Mobile Computing Bruce Scharlau, University of Aberdeen, 2009 Based on android-sdk_1.6-r1
    • Android is part of the ‘build a better phone’ process
      • Open Handset Alliance produces Android
      Bruce Scharlau, University of Aberdeen, 2009 Comprises handset manufacturers, software firms, mobile operators, and other manufactures and funding companies http://www.openhandsetalliance.com/
    • Android is growing Bruce Scharlau, University of Aberdeen, 2009 http://www.admob.com/marketing/pdf/mobile_metrics_jan_09.pdf Small, 1% of online web requests http://metrics.admob.com/ - Sept 2009 Bigger, 10% of online web requests
    • Android makes mobile Java easier Bruce Scharlau, University of Aberdeen, 2009 http://code.google.com/android/goodies/index.html Well, sort of…
    • Android applications are written in Java
      • package com.google.android.helloactivity;
      • import android.app.Activity;
      • import android.os.Bundle;
      • public class HelloActivity extends Activity {
      • public HelloActivity() {
      • }
      • @Override
      • public void onCreate(Bundle icicle) {
      • super.onCreate(icicle);
      • setContentView(R.layout.hello_activity);
      • }
      • }
      Bruce Scharlau, University of Aberdeen, 2009
    • Android applications are compiled to Dalvik bytecode Bruce Scharlau, University of Aberdeen, 2009 Write app in Java Compiled in Java Transformed to Dalvik bytecode Linux OS Loaded into Dalvik VM
    • The Dalvik runtime is optimised for mobile applications
      • Run multiple VMs efficiently
      Bruce Scharlau, University of Aberdeen, 2009 Each app has its own VM Minimal memory footprint
    • Android has many components Bruce Scharlau, University of Aberdeen, 2009 Bluetooth and USB drivers now gone from kernel XMPP gone from application framework
    • Android has a working emulator Bruce Scharlau, University of Aberdeen, 2009
    • All applications are written in Java and available to each other
      • Android designed to enable reuse of components in other applications
      Bruce Scharlau, University of Aberdeen, 2009 Each application can publish its capabilities which other apps can use
    • Android applications have common structure Bruce Scharlau, University of Aberdeen, 2009 Views such as 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 apps to display custom alerts in the status bar An Activity Manager that manages the life cycle of applications and provides a common navigation backstack
    • Android applications have common structure Bruce Scharlau, University of Aberdeen, 2009 Broadcast receivers can trigger intents that start an application Data storage provide data for your apps, and can be shared between apps – database, file, and shared preferences (hash map) used by group of applications Services run in the background and have no UI for the user – they will update data, and trigger events Intents specify what specific action should be performed Activity is the presentation layer of your app: there will be one per screen, and the Views provide the UI to the activity
    • There is a common file structure for applications Bruce Scharlau, University of Aberdeen, 2009 code images files UI layouts constants Autogenerated resource list
    • Standard components form building blocks for Android apps Bruce Scharlau, University of Aberdeen, 2009 Other applications Has life-cycle screen App to handle content Background app Like music player Views manifest Activity Intents Service Notifications ContentProviders
    • The AndroidManifest lists application details
      • <?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?>
      • <manifest xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
      • package=&quot;com.my_domain.app.helloactivity&quot;>
      • <application android:label=&quot;@string/app_name&quot;>
      • <activity android:name=&quot;.HelloActivity&quot;>
      • <intent-filter>
      • <action android:name=&quot;android.intent.action.MAIN&quot;/>
      • <category android:name=&quot;android.intent.category.LAUNCHER&quot;/>
      • </intent-filter>
      • </activity>
      • </application>
      Bruce Scharlau, University of Aberdeen, 2009
    • Activity is one thing you can do Bruce Scharlau, University of Aberdeen, 2009 From fundamentals page in sdk
    • Intent provides late running binding to other apps
      • It can be thought of as the glue between activities. It is basically a passive data structure holding an abstract description of an action to be performed.
      Bruce Scharlau, University of Aberdeen, 2009 Written as action/data pairs such as: VIEW_ACTION/ACTION content://contacts/1
    • Services declared in the manifest and provide support Bruce Scharlau, University of Aberdeen, 2009 Services run in the background: Music player providing the music playing in an audio application Intensive background apps, might need to spawn their own thread so as to not block the application
    • Notifications let you know of background events Bruce Scharlau, University of Aberdeen, 2009 This way you know that an SMS arrived, or that your phone is ringing, and the MP3 player should pause
    • ContentProviders share data Bruce Scharlau, University of Aberdeen, 2009 You need one if your application shares data with other applications This way you can share the contact list with the IM application If you don’t need to share data, then you can use SQLlite database
    • UI layouts are in Java and XML Bruce Scharlau, University of Aberdeen, 2009 setContentView(R.layout.hello_activity); //will load the XML UI file
    • Security in Android follows standard Linux guidelines Bruce Scharlau, University of Aberdeen, 2009 Each application runs in its own process Process permissions are enforced at user and group IDs assigned to processes Finer grained permissions are then granted (revoked) per operations <manifest xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot; package=&quot;com.google.android.app.myapp&quot; > <uses-permission id=&quot;android.permission.RECEIVE_SMS&quot; /> </manifest>
    • There are lots of sources of information
      • The sdk comes with the API references, sample applications and docs/resources/bootcamp.pdf
      • There are Google news groups
      • There is http://www.anddev.org
      • There is Google search
      Bruce Scharlau, University of Aberdeen, 2009