Download Android Virtual Device

Mobile Application
Development using
By: Neeraj Sharma
Basics
Introduction
• Android is a software stack for mobile devices that
includes an operating system, middleware and key
applications.
• Android SDK provides the tools and APIs
necessary to begin developing applications on the
Android platform using the Java programming
language.
• Android is the first complete, open, and free
mobile platform.
Introduction cont.…
• Android, Inc. was founded in Palo Alto, California,
United States in October, 2003 by
• Andy Rubin (co-founder of Danger),
• Rich Miner (co-founder of Wildfire
Communications, Inc.),
• Nick Sears (once VP at T-Mobile),
• Chris White
Introduction cont.…
• Google acquired Android Inc. in August, 2005,
• Making Android Inc. a wholly owned subsidiary of
Google Inc.
• Key employees of Android Inc., including Andy
Rubin, Rich Miner and Chris White, stayed at the
company after the acquisition.
• Till May-11 Google has acquired 96 more
companies
Open Handset Alliance
• Open Handset Alliance (OHA) is a business
alliance of 80 firms to develop open standards for
mobile devices.
• Member firms include Google, HTC, Sony, Dell,
Intel, Motorola, Qualcomm, Texas Instruments,
Samsung, LG, T-Mobil, Nvidia, and Wind River.
• Goal of the Open Handset Alliance is to develop
open standards for mobile devices
Android Features
• Handset layouts
– The platform is adaptable to larger, VGA, 2D
graphics library, 3D graphics library based on
OpenGL ES 2.0 specifications, and traditional
smartphone layouts.
• Storage
– SQLite, a lightweight relational database, is used
for data storage purposes
Android Features
• Connectivity
– Android supports connectivity technologies
including GSM/EDGE, IDEN, CDMA, EV-DO, UMTS,
Bluetooth, Wi-Fi (no connections through Proxy
server and no Ad hoc wireless network), LTE, NFC
and WiMAX.
• Messaging
– SMS and MMS are available forms of messaging,
including threaded text messaging.
Android Features
• Multiple Language Support
– Multiple Languages are available on Android.
• Web browser
– The web browser available in Android is based on the
open-source WebKit layout engine, coupled with
Chrome's V8 JavaScript engine.
• Media support
– WebM, H.263, H.264 (in 3GP or MP4 container),
MPEG-4 SP, AMR, AMR-WB (in 3GP container), AAC,
HE-AAC (in MP4 or 3GP container), MP3, MIDI, Ogg
Vorbis, WAV, JPEG, PNG, GIF, BMP.
Android Features
• Streaming media support
– RTP/RTSP streaming (3GPP PSS, ISMA), HTML
progressive download (HTML5 <video> tag).
– Adobe Flash Streaming (RTMP) and HTTP Dynamic
Streaming are supported by the Flash 10.1 plugin.
– Apple HTTP Live Streaming is supported by RealPlayer
for Mobile and planned to be supported by the
operating system in Android 3.0 (Honeycomb).
– Microsoft Smooth Streaming is planned to be
supported through the awaited port of Silverlight
plugin to Android.
Software development
• Android SDK includes a comprehensive set of
development tools.
• The SDK is downloadable on the android
developer website.
• The officially supported integrated
development environment (IDE) is Eclipse
(currently 3.5 or 3.6) using the Android
Development Tools (ADT) Plugin.
Android Market
• Android Market is the online software store
developed by Google for Android devices.
• Google announced the Android Market on 28
August 2008, and it was available to users on 22
October 2008.
• Support for paid applications was available
from 13 February 2009 for US and UK
developers, with additional support from 29
countries on 30 September 2010.
Android Market
• In February 2011, the Android Market was made
fully accessible on the web, allowing users to browse
and pick up applications using their PCs, send them
to their mobile phone and make comments on
them. All this functionality was previously accessible
only from mobile phone devices.
• Users can install apps directly using APK files, or
from alternative app markets. Unlike Apple, Google
allows independent app stores to operate for
Android.
Downloading and installation
of Android SDK
• Go to: http://developer.android.com/sdk/index.html
Downloading and installation
of Android SDK
Copy the downloaded zip file to c:\program files and unzip it.
Downloading and installation
of Android SDK
The downloaded SDK contains only basic tools that are not
sufficient to develop any application therefore you must
update the SDK using SDK Manager.
Downloading and installation
of Android SDK
Installing Available packages.
Installing the ADT Plugin for
Eclipse
• Download ADT plugin from
http://developer.android.com/sdk/eclipse-adt.html
Installing the ADT Plugin for
Eclipse
• Go to My Eclipse Menu and click MyEclipse
Configuration Center
Installing the ADT Plugin for
Eclipse
Installing the ADT Plugin for
Eclipse
Installing the ADT Plugin for
Eclipse
Installing the ADT Plugin for
Eclipse
Installing the ADT Plugin for
Eclipse
Installing the ADT Plugin for
Eclipse
Android Architecture
Linux Kernel
• Android relies on Linux version 2.6 for core
system services such as security, memory
management, process management, network
stack, and driver model.
• The kernel also acts as an abstraction layer
between the hardware and the rest of the
software stack.
Android Runtime
• Android includes a set of core libraries that
provides most of the functionality available in
the core libraries of the Java programming
language.
• Every Android application runs in its own
process, with its own instance of the Dalvik
virtual machine. Dalvik has been written so
that a device can run multiple VMs efficiently.
Android Runtime
• The Dalvik VM executes files in the Dalvik Executable
(.dex) format which is optimized for minimal memory
footprint.
• The VM is register-based, and runs classes compiled
by a Java language compiler that have been
transformed into the .dex format by the included "dx"
tool.
• The Dalvik VM relies on the Linux kernel for
underlying functionality such as threading and lowlevel memory management.
Libraries
• Android includes a set of C/C++ libraries used by
various components of the Android system. These
capabilities are exposed to developers through the
Android application framework.
Application Framework
• A rich and extensible set of Views that can be used to build an
application, including 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 applications to display
custom alerts in the status bar.
• An Activity Manager that manages the lifecycle of applications and
provides a common navigation backstack.
Applications
• Android will ship with a set of core applications
including an email client, SMS program, calendar,
maps, browser, contacts, and others.
• All applications are written using the Java
programming language.
Dalvik Virtual Machine VS
Java Virtual Machine
• JavaVM’s one can find on almost any desktop
computer nowadays are Stack-based Virtual
Machines (VM).
• The DalvikVM on the other hand is register based,
because on mobile-processors are optimized for
register-based execution.
• Also of register-based VMs allow faster execution
times at the expense of programs which are larger
after compilation.
Application Architecture
• The Android operating system is a multi-user
Linux system in which each application is a
different user.
• By default, the system assigns each application a
unique Linux user ID (the ID is used only by the
system and is unknown to the application).
• Each process has its own virtual machine (VM), so
an application's code runs in isolation from other
applications.
Application Architecture
• By default, every application runs in its own Linux
process.
• Android starts the process when any of the
application's components need to be executed,
then shuts down the process when it's no longer
needed or when the system must recover
memory for other applications.
Application Components
• Application components are the essential building
blocks of an Android application.
• There are four different types of application
components.
• Each type serves a distinct purpose and has a
distinct lifecycle that defines how the component
is created and destroyed.
Activities
• An activity represents a single screen with a user
interface.
• An activity is implemented as a subclass of
Activity.
Services
• A service is a component that runs in the
background to perform long-running operations
or to perform work for remote processes.
• A service does not provide a user interface.
• For example, a service might play music in the
background while the user is in a different
application.
• A service is implemented as a subclass of Service.
Content providers
• A content provider manages a shared set of
application data.
• You can store the data in the file system, a SQLite
database, on the web, or any other persistent
storage location your application can access.
• Through the content provider, other applications
can query or even modify the data (if the content
provider allows it).
Content providers
• Content providers are also useful for reading and
writing data that is private to your application and
not shared.
• A content provider is implemented as a subclass
of ContentProvider and must implement a
standard set of APIs that enable other
applications to perform transactions.
Broadcast receivers
• A broadcast receiver is a component that responds to
system-wide broadcast announcements.
• Many broadcasts originate from the system
for example,
a broadcast announcing that the screen has turned off,
the battery is low, or
a picture was captured.
Broadcast receivers
• A broadcast receiver is implemented as a
subclass of BroadcastReceiver and each
broadcast is delivered as an Intent object.
Managing Projects
• There are three types of projects, and they all
share the same general structure but differ in
function:
– Android Project
– Test Project
– Library Project
Test Project
• These projects contain code to test your
application projects and are built into
applications that run on a device.
Library Project
• These projects contain shareable Android
source code and resources that you can
reference in Android projects.
• This is useful when you have common code
that you want to reuse.
• Library projects cannot be installed onto a
device; however, they are pulled into the .apk
file at build time.
Set Project as Library
1. In the Package Explorer, right-click the library
project and select Properties.
2. In the Properties window, select the "Android"
properties group at left and locate the Library
properties at right.
3. Select the "is Library" checkbox and click Apply.
4. Click OK to close the Properties window.
Set Project as Library
Referencing a Library Project
To add a reference to a library project, follow these steps:
1. In the Package Explorer, right-click the dependent project
and select Properties.
2. In the Properties window, select the "Android" properties
group at left and locate the Library properties at right.
3. Click Add to open the Project Selection dialog.
4. From the list of available library projects, select a project
and click OK.
5. When the dialog closes, click Apply in the Properties
window.
6. Click OK to close the Properties window.
Referencing a Library Project
Building and Running
• During the build process, your Android projects are
compiled and packaged into an .apk file, the
container for your application binary.
• It contains all of the information necessary to run
your application on a device or emulator.
• such as compiled .dex files (Dalvik byte code), a
binary version of the AndroidManifest.xml file,
compiled
resources
(resources.arsc)
and
uncompiled resource files for your application.
Building and Running
• In Eclipse, the ADT plugin incrementally builds
your project as you make changes to the
source code.
• Eclipse outputs an .apk file automatically to
the bin folder of the project, so you do not
have to do anything extra to generate the
.apk.
Building and Running
Android Debug Bridge (ADB)
All Android applications must be digitally signed before the system will
install them on an emulator or device.
There are two ways to do this:
1. with a debug key (for immediate testing on an emulator or development
device)
2. with a private key (for application distribution).
Creating a Sample Application
Open Eclipse go to
New->Android Project
Project Structure
The AndroidManifest.xml File
• Every application must have an AndroidManifest.xml file.
• The manifest presents essential information about the
application to the Android system.
• Information the system must have before it can run any
of the application's code.
• Among other things, the manifest does the following:
The AndroidManifest.xml File
• It names the Java package for the application. The
package name serves as a unique identifier for the
application.
• It describes the components of the application — the
activities, services, broadcast receivers, and content
providers that the application is composed of.
• It determines which processes will host application
components.
The AndroidManifest.xml File
• It declares which permissions the application must have
in order to access protected parts of the API and interact
with other applications.
• It also declares the permissions that others are required
to have in order to interact with the application's
components.
• It declares the minimum level of the Android API that the
application requires.
The AndroidManifest.xml File
• It lists the Instrumentation classes that provide profiling
and other information as the application is running.
– These declarations are present in the manifest only while the
application is being developed and tested; they're removed
before the application is published.
• it lists the libraries that the application must be linked
against.
AVD (Android Virtual Device)
• 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.
• From the Eclipse Toolbar click the Android SDK and AVD
Manager Button.
• This will open a window, from the list select “Virtual
Devices”, and click New Button.
AVD (Android Virtual Device)
AVD (Android Virtual Device)
User Interface and
Layouts
View
• The package android.view provides classes and
interfaces related to drawing on the screen.
• android.view.View is a high level abstraction of all views.
• Package android.widget provides diff. controls.
Layouts
• A layout control is still a View object.
• It doesn’t actually draw anything specific on the screen.
• It is a parent container for organizing other controls
(children).
• It determine how and where on the screen child
controls are drawn.
Types of Layout
• Linear Layout
• Table Layout
• Relative Layout
• Absolute Layout
• Frame Layout
View Hierarchy
LinearLayout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello, I am a TextView" />
<Button android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello, I am a Button" />
</LinearLayout>
Linear Layout
• This design has 3 Linear layouts.
• First is the Main Container layout with
vertical orientation.
• Then it contains 2 Linear Layouts with
Vertical orientation.
• The second layout has 4 children.
• The third layout also has 4 children's.
Linear Layout
Second Layout with Horizontal Orientation
Main Container Layout
With vertical orientation
Row one
Row two
Third Layout with Vertical Orientation
Row Three
Row Four
Linear Layout
<LinearLayout android:layout_width="fill_parent" android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout android:orientation="horizontal">
<!--Put your child views here-->
</LinearLayout>
<LinearLayout android:orientation="vertical">
<!--Put your child views here-->
</LinearLayout>
</LinearLayout>
Load the XML Resource
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main_layout);
}
Name of your layout file stored in res/layout folder
Change this name to change layout of your activity
Table Layout
• TableLayout is a ViewGroup that displays child View
elements in rows and columns.
Table Layout
<TableLayout>
<TableRow>
<!--Put your child views here-->
</TableRow>
<TableRow>
<!--Put your child views here-->
</TableRow>
</TableLayout>
Relative Layout
<RelativeLayout>
<TextView android:id="@+id/label" android:text="Text"/>
<EditText
<Button
android:id="@+id/entry"
android:layout_below="@id/label"/>
android:id="@+id/ok"
android:layout_below="@id/entry"
android:text="OK"
android:layout_alignParentRight="true"/>
</RelativeLayout>
Spinner
• Spinner is a widget similar to a drop-down list for selecting items
Spinner Control
Title or Prompt text
List of items also known as Adapter View
A Single Row
Creating Array
<string name="country_prompt">Choose a country</string>
<string-array name="country_array">
<item>India</item>
<item>USA</item>
<item>China</item>
<item>Japan</item>
<item>Korea</item>
</string-array>
Edit strings.xml file to add
string and string array
Add Spinner to layout
<Spinner android:id="@+id/spinner"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:prompt="@string/country_prompt"
android:entries="@array/country_array"
/>
Get Spinner into Java
Spinner s = (Spinner) findViewById(R.id.spinner);
s.setOnItemSelectedListener(this);
implements OnItemSelectedListener
public void onItemSelected(AdapterView<?> parent, View v, int
position,long rowId) {}
public void onNothingSelected(AdapterView<?> arg0) {}
CheckBox
<CheckBox android:id="@+id/checkbox"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="check it out" />
public void onCheckedChanged(CompoundButton View, boolean isChecked)
{
if (isChecked)
Toast.makeText(this, "Selected",Toast.LENGTH_SHORT).show();
else
Toast.makeText(this, "Not selected", Toast.LENGTH_SHORT).show();
}
Creating an AlertDialog
• An AlertDialog is an extension of the Dialog class.
• It is used for dialogs that use any of the following features:
–
–
–
–
A title
A text message
One, two, or three buttons
A list of selectable items (with optional checkboxes or radio
buttons)
Creating an AlertDialog
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Are you sure you want to exit?")
.setCancelable(false)
.setPositiveButton("Yes", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int id) {}
}).setNegativeButton("No", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int id)
{
dialog.cancel();
}
}).create().show();
Adding a list
final String[] items = {"Red", "Green", "Blue"};
builder.setItems(items,new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int item)
{
Toast.makeText(getApplicationContext(), items[item], Toast.LENGTH_SHORT).show();
}
});
Adding checkboxes and radio buttons
builder.setSingleChoiceItems(items, -1,
new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int item)
{
Toast.makeText(getApplicationContext(),items[item],Toast.LENGTH_SHORT).show();
}
});
Creating a ProgressDialog
ProgressDialog dialog = ProgressDialog.show(this,"", "Loading...", true);
ProgressDialog progressDialog;
progressDialog = new ProgressDialog(MyActivity.this);
progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
progressDialog.setMessage("Loading...");
progressDialog.setCancelable(false);
progressDialog.show();
Intents
• Activities, services, and broadcast receivers — are
activated through messages, called intents.
• Intent messaging is a facility for late run-time
binding between components in the same or
different applications.
• Intent object, is a data structure holding a
description of an operation to be performed.
Intent Resolution
• Implicit intents
– Implicit intents are often used to activate components in
other applications.
• Explicit intents
– Designate the target component by its name
Intent
• Action
– A string naming the action to be performed.
• Data and Type
– The URI of the data to be acted on and the MIME type of
that data.
• Category
– A string containing additional information about the kind
of component that should handle the intent.
Making a call from an Activity.
Intent intent = new Intent(Intent.ACTION_CALL);
intent.setData(Uri.parse("tel:123455"));
startActivity(intent);
<uses-permission android:name="android.permission.CALL_PHONE" />
Calling Default Web Browser
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse("http://www.google.com"));
startActivity(intent);
<uses-permission android:name="android.permission.INTERNET"/>
Open Maps
Uri uri = Uri.parse("geo:38.899533,-77.036476");
Intent it = new Intent(Intent.ACTION_VIEW,uri);
startActivity(it);
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission
android:name="android.permission.ACCESS_FINE_LOCATION" />
Open Contacts
Intent intent = new Intent
(Intent.ACTION_VIEW,Uri.parse("content://contacts/people"));
startActivity(intent);
<uses-permission android:name="android.permission.READ_CONTACTS"/>
Intent Filter
• The Android system will determine suitable applications
for an implicit intent and if several applications exist offer
the user the choice to open one.
• The determination is based on intent filters.
• To react to a certain implicit intent an application
component must register itself via an IntentFilter in the
"AndroidManifest.xml" to this event.
• Otherwise it can only be called by explicit intents.
Intent Filter example
<intent-filter >
<action android:name="android.intent.action.SEND"/>
<data android:mimeType="image/*"/>
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
Code to Handle intent
ImageView iv=(ImageView)findViewById(R.id.imageView1);
if( getIntent().getExtras()!=null)
iv.setImageURI((Uri) getIntent().getExtras().get(Intent.EXTRA_STREAM));
Explicit Intent
Intent intent = new Intent(this,SecondActivity.class);
intent.putExtra("name", "Neeraj Sharma");
startActivity(intent);
/*Getting extras in second activity*/
Bundle bundle = this.getIntent().getExtras();
String str = bundle.getString("name");
System.out.println("Name ::"+str);
Calling activity for result
Intent intent = new Intent(this,SecondActivity.class);
intent.putExtra("name", "Neeraj");
startActivityForResult(intent,1);
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch(requestCode){
case 1:
if(resultCode == RESULT_OK){
if(data != null) {
Bundle bundle = data.getExtras();
String str = bundle.getString("Surname");
System.out.println("Surname :"+str);
}}
break;
}
super.onActivityResult(requestCode, resultCode, data);
}
Code for Second Activity
public boolean onKeyDown(int keyCode, KeyEvent event)
{
if(keyCode == KeyEvent.KEYCODE_BACK)
{
Intent data = new Intent();
data.putExtra("surname", "Sharma");
setResult(RESULT_OK, data);
this.finish();
return true;
}
return false;
}
Location
Introduction
• One of Google’s most popular services-after searches is
Google Maps.
• Android integrates Google Maps.
• There is a mapping activity available to users straight off
the main Android launcher.
• More relevant to you, as a developer, are MapView and
MapActivity.
• Which allow you to integrate maps into your own
applications.
Working with Location-Based Services
• The location-based services facility in Android sits on
two pillars
– The mapping API (com.google.android.maps )
provide facilities for you to display a map and manipulate it.
– And the Location API (android.location)
It handles GPS data and real-time location data.
• These APIs reach across the Internet to invoke services
from Google servers. Therefore Internet connectivity is
compulsory for these to work.
Obtaining a map-api Key from Google
• The two keys
– 1. for emulator 2. For the device
Because the certificate used to obtain the map-api key will differ
between development and production.
• The ADT plug-in uses the debug certificate during
development.
• For production deployment, you’ll likely use a selfsigned certificate to sign your .apk file.
• To obtain a map-api key, you need the certificate that
you’ll use to sign your application.
Obtaining a map-api Key from Google
• First you must locate your debug certificate, which is
generated and maintained by Eclipse.
Obtaining a map-api Key from Google
• keytool -list -alias androiddebugkey -keystore "FULL
PATH OF YOUR debug.keystore FILE" -storepass android keypass android
Obtaining a map-api Key from Google
http://code.google.com/android/maps-api-signup.html
Obtaining a map-api Key from Google
http://code.google.com/android/maps-api-signup.html
Permissions & Library to use Maps
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-library android:name="com.google.android.maps"/>
MapView
<com.google.android.maps.MapView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:apiKey="Your map API Key Goes Here"
android:id="@+id/mapview"
android:clickable="true"
/>
Using Overlays
• Google Maps provides a facility that allows you to
place custom data on top of the map
Using Overlays
• Maps provides this facility is by allowing you to add a
layer on top of the map.
• Android provides several classes that help you to add
layers to a map.
• The key class for this type of functionality is Overlay, but
you can use an extension of this class called
ItemizedOverlay.
• Apart from ItemizedOverlay we have to use number of
other classes so first we take a brief overview of each
class that we will use.
Using Overlays
• Drawable
– setBounds(rect), getIntrinsicHeight() and getIntrinsicWidth()
• GeoPoint
– An immutable class representing a pair of latitude and longitude,
stored as integer numbers of micro degrees (degrees * 1E6).
Latitude and Longitude
• Any location on Earth is described by two numbers--its
latitude and its longitude.
ItemizedOverlay
• A sub class for an Overlay which consists of a list of
OverlayItems.
• This handles sorting north-to-south for drawing, creating
span bounds, drawing a marker for each point, and
maintaining a focused item.
• It also matches screen-taps to items, and dispatches Focuschange events to an optional listener.
ItemizedOverlay
Drawable marker = getResources().getDrawable(R.drawable.map_marker);
marker.setBounds(0, 0, marker.getIntrinsicWidth(), marker.getIntrinsicHeight());
GeoPoint
GeoPoint disneyMagicKingdom = new GeoPoint((int) (28.418971 * 1E6), (int) (-81.581436 * 1E6));
GeoPoint disneySevenLagoon = new GeoPoint((int) (28.410067 * 1E6), (int) (-81.583699 * 1E6));
OverlayItems
class InterestingLocations extends ItemizedOverlay
{
private List<OverlayItem> locations = new ArrayList<OverlayItem>();
private Drawable marker;
public InterestingLocations(Drawable marker) {
super(marker);
this.marker = marker;
GeoPoint disneyMagicKingdom = new GeoPoint((int) (28.418971 * 1E6), (int) (-81.581436 * 1E6));
GeoPoint disneySevenLagoon = new GeoPoint((int) (28.410067 * 1E6), (int) (-81.583699 * 1000000));
locations.add(new OverlayItem(disneyMagicKingdom, "Magic Kingdom","Magic Kingdom"));
locations.add(new OverlayItem(disneySevenLagoon, "Seven Lagoon","Seven Lagoon"));
populate();
}
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
super.draw(canvas, mapView, shadow);
boundCenterBottom(marker);
}
protected OverlayItem createItem(int i) {
return locations.get(i);
}
public int size() {
return locations.size();
}}
OverlayItems
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
mapView.setClickable(true);
Drawable marker = getResources().getDrawable(R.drawable.map_marker);
marker.setBounds(0, 0, marker.getIntrinsicWidth(), marker.getIntrinsicHeight());
InterestingLocations funPlaces = new InterestingLocations(marker);
mapView.getOverlays().add(funPlaces);
GeoPoint pt = funPlaces.getCenter(); // get the first-ranked point
mapView.getController().setCenter(pt);
mapView.getController().setZoom(15);
OverlayItems
Geocoding with Android
• Converting an address (or location) to a latitude / longitude pair is
known as geocoding.
• android.location.Geocoder class provides this facility.
• Geocoder class provides both forward and backward conversion.
– Address to co-ordinates
– Co-ordinates to list of address
GeoCoder
List<Address> getFromLocation(double latitude, double longitude, int
maxResults)
List<Address> getFromLocationName(String locationName, int
maxResults, double lowerLeftLatitude, double lowerLeftLongitude,
double upperRightLatitude, double upperRightLongitude)
List<Address> getFromLocationName(String locationName, int
maxResults)
Layout
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout android:layout_width="fill_parent" android:layout_alignParentBottom="true"
android:orientation="vertical"
android:layout_height="wrap_content">
<EditText android:layout_width="fill_parent" android:layout_height="wrap_content"
android:text="White House"
android:id="@+id/location"/>
<Button
android:id="@+id/geocodeBtn"
android:text="Find Location"
android:layout_width="wrap_content"
android:layout_height="wrap_content" /></LinearLayout>
<com.google.android.maps.MapView android:id="@+id/geoMap"
android:clickable="true"
android:layout_width="fill_parent"
android:layout_height="320px"
android:apiKey="YOUR API KEY GOES HERE" />
</RelativeLayout>
Layout
public class GeocodingDemoActivity extends MapActivity{
Geocoder geocoder = null;
MapView mapView = null;
protected boolean isLocationDisplayed() {
protected boolean isRouteDisplayed() {
return false; }
return false; }
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mapView = (MapView)findViewById(R.id.geoMap);
mapView.setBuiltInZoomControls(true);
// lat/long of Jacksonville, FL
int lat = (int)(30.334954*1E6);
int lng = (int)(-81.5625*1E6);
GeoPoint pt = new GeoPoint(lat,lng);
mapView.getController().setZoom(10);
mapView.getController().setCenter(pt);
Layout
Button geoBtn =(Button)findViewById(R.id.geocodeBtn);
geocoder = new Geocoder(this);
geoBtn.setOnClickListener(new OnClickListener(){
public void onClick(View arg0) {
try {
EditText loc = (EditText)findViewById(R.id.location);
String locationName = loc.getText().toString();
List<Address> addressList = geocoder.getFromLocationName(locationName, 5);
if(addressList!=null && addressList.size()>0){
int lat = (int)(addressList.get(0).getLatitude()*1E6);
int lng = (int)(addressList.get(0).getLongitude()*1E6);
GeoPoint pt = new GeoPoint(lat,lng);
mapView.getController().setZoom(15);
mapView.getController().setCenter(pt);
}
} catch (IOException e) {
}});
}}
e.printStackTrace(); }
LocationManager and LocationProvider
• A LocationProvider provides location data using several
metrics, and you can access providers through a
LocationManager.
• LocationManager allows you to attach a LocationListener
that receives updates when the device location changes.
• This service provides two things: a mechanism for you to
obtain the device’s geographical location, and a facility for
you to be notified (via an intent) when the device enters a
specified geographical location.
LocationManager and LocationProvider
LocationManager locMgr =(LocationManager)getSystemService (Context.LOCATION_SERVICE);
Location loc = locMgr.getLastKnownLocation(LocationManager.GPS_PROVIDER);
List<String> providerList = locMgr.getAllProviders();
for( String s: providerList)
Log.v("Location Manager ",s);
Listening location updates
LocationManager locMgr = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationListener locListener = new LocationListener() {
public void onLocationChanged(Location location) {
if (location != null)
Toast.makeText(getBaseContext(),"New location latitude [" + location.getLatitude()+
"] longitude [" + location.getLongitude()+ "]", Toast.LENGTH_SHORT).show();
}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {
}
};
locMgr.requestLocationUpdates(LocationManager.GPS_PROVIDER,
0, // minTime in ms
0, // minDistance in meters
locListener);
Assignment
• Explore and Learn about MyLocationOverlay class and
explain with a running example