Android is an open source operating system developed by Google and the Open Handset Alliance. This document provides an overview of Android and how to create a sample Android project in Eclipse. It discusses Android versions, the project components like activities and services, and how to add a layout, strings, and additional activities. Creating the sample project involves adding buttons, text views and intents to launch a new activity when a button is clicked.

1. Android Development
Made Easy W I t h S a m
p l e P r o j e c t
by Joemarie Comeros Amparo

2. Outline:
 Overview on Android
 Installing ADT on Eclipse
 Explore Project Components
 Sample Project

3. Android is an open mobile phone platform that was
developed by Google and later by Open Handset
Alliance. Google defines Android as a "software
stack" for mobile phones.
Software stack is made up of operating system(the
platform on which everything runs), the middleware
(the programming that allows applications to talk to
a network and to one another) and the applications
(the actual programs that phone will run)

4. July 2005 - Google Inc. bought from Danger Inc
Open Handset Alliance was formed headed by Google
which is composed of companies like Intel, T-
Mobile, Spring Nextel and more.
In 2008, Android became available as an open source
and ASOP(Android Open Source Project) is
responsible for maintaining and development of
android.
February 2009, the first android version was released,
Android 1.1. for Mobile G1.

5.  Android 1.1
 Android 1.5 Cupcake
 Android 1.6 Donut
 Android 2.0/2.1 Eclair
 Android 2.2.x Froyo
 Android 2.3.x Gingerbread
 Android 3. x Honeycomb
 Android 4.0.x Ice Cream Sandwich
 Android 4.1 Jelly Bean

6. Note: When developing an application, consider the market share of the android version. The
higher the market share, the higher number your target market is.

7. Note: Based on my development experience, ADT can run on at least Dual Core with at
least 2GB RAM.

8. Please refer to:
www.developershaven.net

9. Activity
• Present a visual user interface for one focused endeavor the user can undertake
• Example: a list of menu items users can choose from
Services
• Run in the background for an indefinite period of time
• Example: calculate and provide the result to activities that need it
Broadcast Receivers
• Receive and react to broadcast announcements
• Example: announcements that the time zone has changed
Content Providers
• Store and retrieve data and make it accessible to all applications
• Example: Android ships with a number of content providers for common
Intents
• Hold the content of a message
• Example: convey a request for an activity to present an image to the user or let
the user edit some text

11. public class CCSActivity extends Activity {
/** Called when the activity is first created.
*/
@Override
public void onCreate(Bundle
savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
}

12.  Run in the background
 Can continue even if Activity that started it dies
 Should be used if something needs to be done while the
user is not interacting with application
 Otherwise, a thread is probably more applicable
 Should create a new thread in the service to do work in,
since the service runs in the main thread
 Can be bound to an application
 In which case will terminate when all applications bound to
it unbind
 Allows multiple applications to communicate with it via a
common interface
 Needs to be declared in manifest file
 Like Activities, has a structured life cycle

14. SRC
• The project source code
GEN
• Auto generated code
• Example: R.java
Included libraries
Resources
• Drawables
• Layout
• Values like strings
Manifest File
• A must have xml file. Contains essential information about the
system to the android system

16.  Auto-generated: you shouldn’t edit it
 Contains IDs of the project resources
 Enforces good software engineering
 Use findViewById and Resources object to get
access to the resources
 Ex. Button b = (Button)findViewById(R.id.button1)
 Ex. getResources().getString(R.string.hello));

19.  Eclipse has a great UI creator
 Generates the XML for you
 Composed of View objects
 Can be specified for portrait and landscape
mode
 Use same file name, so can make completely
different UIs for the orientations without
modifying any code

21.  Click ‘Create’ to make layout modifications
 When in portrait mode can select ‘Portrait’ to
make a res sub folder for portrait layouts
 Likewise for Landscape layouts while in landscape mode
 Will create folders titled ‘layout-port’ and ‘layout-land’
 Note: these ‘port’ and ‘land’ folders are examples
of ‘alternate layouts’, see here for more info
 http://developer.android.com/guide/topics/resources/providing-
resources.html
 Avoid errors by making sure components have the
same id in both orientations, and that you’ve
tested each orientation thoroughly

23. <?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/ap
k/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
android:id="@+id/tv_hello"/>
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Large Text“
android:textAppearance="?android:attr/textApp res/values/string.xml
earanceLarge"/>
</LinearLayout>

25. 1. Lunching a new activity without expecting without expecting a result
2. Lunching a new activity and expecting a result when it finished.
CalledActivity.class

26.  On Eclipse IDE. Go To File >
New > Project > Android
Project
 See image at the side for the
prompt that appear. Click
next button.

27.  Select android version.
Tip: select the latest OS
version available. You can
add minimum and target SDK
on your manifest file to
support earlier android
versions.

28.  Provide package name of
your project. Valid package
name consist of two names
separated by a period.

29.  Provide package name of
your project. Valid package
name consist of two names
separated by a period.
 Optional: Change minimum
SDK for the lowest android
version your application will
support.
 Hit on finish

30.  Under res/layout on your In main.xml:
project explorer. Open <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
main.xml. Create a layout android:layout_height="fill_parent"
android:orientation="vertical" >
like this: <TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/button1" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button 2" />
<Button
android:id="@+id/button3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button 3" />
</LinearLayout>
<EditText
android:id="@+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10" >
<requestFocus />
</EditText>
</LinearLayout>

31.  Under res/values on your
project explorer. Open
strings.xml.
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="hello">Hello World, SampleProjectActivity!</string>
<string name="app_name">SampleProject</string>
<string name="button1">Button 1 Clicked.</string>
</resources>
NOTE: string with name button1 is being referenced by Button 1 android:text property.
See main.xml in your layout.

32.  Under SRC on your project public class SampleProjectActivity extends Activity implements OnClickListener{
explorer. Open
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
SampleProjectActivity.java.
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Toast.makeText(this, "Hello.", Toast.LENGTH_LONG).show();
//referencing components in our layout as set in setContentView, - main.xml
Change code to this: //findViewById is used hence we components in our layout will be called
//through their ids as set in android:id properties. See main.xml in your layout.
Button btn1 = (Button)findViewById(R.id.button1);
//one way in handling click event
 See comments for better btn1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
understand. application
//Toast is a prompt that will notify user of what has happened in the
//but not requiring user an action.
Toast.makeText(getApplication(), "Button 1 Clicked",
Toast.LENGTH_LONG).show();
}
});
import android.app.Activity; Button btn2 = (Button)findViewById(R.id.button2);
import android.content.Intent; Button btn3 = (Button)findViewById(R.id.button3);
//Other way of handling event inside an activity
import android.os.Bundle; btn2.setOnClickListener(this);
btn3.setOnClickListener(this);
import android.view.View; }
@Override
import public void onClick(View v) {
// TODO Auto-generated method stub
android.view.View.OnClickListener; switch(v.getId())
{
import android.widget.Button; case R.id.button2:
EditText editText = (EditText)findViewById(R.id.editText1);
import android.widget.EditText; editText.setText("Button 2 Clicked!");
break;
case R.id.button3:
import android.widget.Toast; // Intent with out waiting for result.
// This is creating a new view and passing the new controll to the next view.
Intent intent = new Intent(this, NextActivity.class);
startActivity(intent);
break;
}
}
}

33.  Create NextActivity.java import android.app.Activity;
import android.os.Bundle;
 Right click SRC folder > New import android.widget.Button;
import android.widget.TextView;
> Class. public class NextActivity extends Activity{
 Change code to this: @Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
// you can have a new layout. but for this example
// we will be reusing the main.xml as our layout.
// we will just manipulate the text to inform user that
//a new activity has been created.
setContentView(R.layout.main);
// setTitle - change the title of the next view
setTitle("Next Activity");
//setting page title
TextView pageTitle =
(TextView)findViewById(R.id.pagetitle);
pageTitle.setText("Hello, You are now in the Next
Activity Class.");
Button btn1 = (Button)findViewById(R.id.button1);
btn1.setText("Option 1");
Button btn2 = (Button)findViewById(R.id.button2);
btn2.setText("Option 2");
Button btn3 = (Button)findViewById(R.id.button3);
btn3.setText("Option 3");
}
}

34.  Open Manifest.xml in your <?xml version="1.0" encoding="utf-8"?>
project explorer. <manifest
xmlns:android="http://schemas.android.com/apk/re
s/android"
 Register NextActivity class to package="com.sample"
android:versionCode="1"
your project. android:versionName="1.0" >
 Your new manifest file must <uses-sdk android:minSdkVersion="8"
android:targetSdkVersion="15"/>
look like the code at the <application
android:icon="@drawable/ic_launcher"
side. android:label="@string/app_name" >
<activity
 Save all the changes android:name=".SampleBradActivity"
android:label="@string/app_name" >
<intent-filter>
<action
android:name="android.intent.action.MAIN" />
<category
android:name="android.intent.category.LAUNCHE
R" />
</intent-filter>
</activity>
<activity
android:name=".NextActivity"
android:label="@string/app_name" />
</application>
</manifest>

35.  Right click your project name in your project explorer > RUN AS
> ANDROID APPLICATION.
 Emulator will boot up. Wait until home screen is shown.
 Your application will be displayed on the screen.
 You can now enjoy the application.
Congratulations!!!

36.  Installation: http://developershaven.net
 Google API: http://mfarhan133.wordpress.com/2010/10/01/generate-google-maps-api-key-for-android/
 Android Developer’s Website : http://developer.android.com/index.html
 Numerous Forums & other developer sites, including:
 http://www.javacodegeeks.com/2011/02/android-google-maps-tutorial.html
 http://efreedom.com/Question/1-6070968/Google-Maps-Api-Directions
 http://stackoverflow.com
 http://www.anddev.org/google_driving_directions_-_mapview_overlayed-t826.html

37. Joemarie Comeros Amparo
about.me/joemarieamparo
Skype/Ymail/Gmail : joemarieamparo
Facebook: joemarieamparo@yahoo.com