1 Hour Android Bootcamp - Michiel Helvensteijn · Bluetooth Noti cations Michiel Helvensteijn 112 Hour Android Bootcamp Android has a common pattern of exposing the functionality

11⁄2 Hour Android Bootcamp

Michiel Helvensteijn

Studievaardigheden, 30-10-2012

Introduction

I was invited to give a presentation for the subject Studievaardigheden at Leiden University: a brief demonstrationof how to develop an Android app. I’m afraid that even with this summary sheet, you will not be able to get thefull benefit of the presentation, because most of it was an actual demonstration inside Eclipse. I just write thesesheets for completeness sake. However, I can highly recommend MarakanaTechTV’s Android Bootcamp Series athttp://www.youtube.com/playlist?list=PLE08A97D36D5A255F

1 The Fundamentals

1.1 MarakanaTechTV’s Android Bootcamp

The FundamentalsHello World!A Real App

MarakanaTechTV’s Android BootcampAndroid PlatformAndroid Programming

The FundamentalsMarakanaTechTV’s Android Bootcamp

http://www.youtube.com/playlist?list=PLE08A97D36D5A255F

Michiel Helvensteijn 11⁄2 Hour Android Bootcamp

This is an excellent series of videos that actually taught me a lot ofthe basics (though that was an earlier iteration of the Bootcamp).They gave me the idea to use the ‘live programming’ format for thispresentation.

Just one thing: those videos can be. . . painfully slow. And 11⁄2hours will probably be way too fast. I give this presentation only togive you a taste of how things look and feel.

Oh, yeah, and I’m stealing a few slides from them (just a few).

1.2 Android Platform



The FundamentalsAndroid Platform

Version API Level NicknameAndroid 1.0, 1.1 1, 2 Android

Android 1.5 3 Cupcake

Android 1.6 4 Donut

Android 2.0, 2.0.1, 2.1 5, 6, 7 Eclair

Android 2.2 8 FroYo

Android 2.3, 2.3.3 9, 10 Gingerbread

Android 3.0, 3.1, 3.2 11, 12, 13 Honeycomb

Android 4.0.2, 4.0.4 14, 15 Ice Cream Sandwich

Android 4.1.1, 4.2 16, 17 Jelly Bean


The API level is the thing developers actually care about. You wantto target a level as high as possible to be able to offer the best newfeatures; but you want to support a level as low as possible, gracefullydegrading your app so that people with old phones can still use it.



The FundamentalsAndroid Platform


This is very cool. Android is built upon the Linux Kernel. Only thekernel, mind you.

The Libraries on top of it are all open source and optimized for amobile environment. We don’t care about caching as much, becauseeverything is flash memory. We do care about battery life.

On top of that, we have the Application Framework. This is theonly thing app developers have access to, and this is what correspondsto a specific ‘API Level’.

1.3 Android Programming



The FundamentalsAndroid Programming


Android programming is Java programming. Most of what you cando with Java, you can do with Android. But the ‘way of working’ cansometimes be quite different.





You can actually program for Android without any IDE. Everythingis available on the command line. But Eclipse makes the go work in-finitely more smoothly. They’ve put quite some work into the AndroidEclipse plugin. You should probably use it.




Main Building BlocksActivity

Service

Broadcast Receiver

Content Provider

Intent


Activities are visible screens on the phone. They have layouts, buttons,text and that kind of thing. A Service is a unit that can run code inthe background without necesserily having anything visible (by defaultthey don’t run in a separate thread, though). A Broadcast Receivercan pick up all kinds of signals from the system, other apps - or itself- and react to them in some way (like notifying other parts of theapp). A Content Provider makes data from your app available toother apps, so they can all work with the same data-set. All of thesecommunicate with each other by sending Intents. In this presentationwe only concern ourselves with activities, services and intents.




ManagersMedia

Internet

Phone

Bluetooth

Notifications


Android has a common pattern of exposing the functionality of thedevice and operating system to app developers: Managers. This slidelists just a few example aspects that can be controlled through Man-agers.




http://developer.android.com


As an Android developer, there is a single website that will be mostimportant to you. The official API reference on the Android Developerwebsite.

2 Hello World!


Hello World!

Create a newAndroid Application Project

in Eclipse



Hello World!

Explore the GUI Designer

Activities

Layouts

Widgets

Toolbars

Properties



Hello World!

Create and RunHello World 0.1



Hello World!

Explore App Anatomy (files)

Manifest.xml

Resources in res/

Java code in src/

(Libraries in libs/)

(Assets in assets/)



Hello World!

Implement Interactivity

Hello World 0.2!


3 A Real App

3.1 Activities


ActivitiesServicesIntents

A Real AppActivities


Activities have a well-defined lifecycle. App developers cannot directlycontrol this lifecycle (merely hint / request), but can dictate how theiractivity behaves on transitions between phases. For this purpose thereis a set of methods that you can overwrite when you inherit from theActivity class. This way you can always request or release resources,save data or do anything else to make sure your activity behaves prop-erly no matter what the user or the operating system does.




Use Logcat; Live Logcat

Log Activity Lifecycle

TAG, you’re it!





Create a ‘Real’ App





Our Stages of DevelopmentCreate an Activity for scheduling the alarm

Test; Log

Create a Service that can trigger an alarm

Test; Log

Connect the two with Intents

Meh. . . It probably works. . .





Create an Activity

for Scheduling the Alarm

Message

Frequency

Period





Create a Servicethat can Trigger an Alarm


3.2 Services



A Real AppServices


Like activities, services also have a lifecycle, but a much easier one.They are created, started and then destroyed. Nonetheless, it is im-portant that you prepare your service to be killed at any time whenthe OS decides that it needs to kill it to reallocate resources.



A Real AppServices

Log Service Lifecycle




A Real AppServices

Try IntentService;

it’s easier. . .




A Real AppServices

Call a Notificationusing NotificationManager




A Real AppServices

Schedule the Notificationusing AlarmManager


3.3 Intents



A Real AppIntents

Send our Alarm Informationusing Intent extras




A Real AppIntents

Do we have Time?Feature Ideas?


Conclusion


Conclusion

www.mhelvens.net


Thanks for reading!

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1 Hour Android Bootcamp - Michiel Helvensteijn · Bluetooth Noti cations Michiel Helvensteijn 112 Hour Android Bootcamp Android has a common pattern of exposing the functionality