developing google android mobile clients for web …
TRANSCRIPT
DEVELOPING GOOGLE ANDROID MOBILE CLIENTS
FOR WEB SERVICES
_______________
A Thesis
Presented to the
Faculty of
San Diego State University
_______________
In Partial Fulfillment
of the Requirements for the Degree
Master of Science
in
Computer Science
_______________
by
Sri Tulasi Peddola
Spring 2012
iii
Copyright © 2012
by
Sri Tulasi Peddola
All Rights Reserved
iv
DEDICATION
I would like to dedicate this thesis to my parents, who have been an everlasting
source of inspiration in my life. I would not have been able to achieve what I have without
their support.
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ABSTRACT OF THE THESIS
Developing Google Android Mobile Clients for Web Services by
Sri Tulasi Peddola Master of Science in Computer Science
San Diego State University, 2012
Web Services, which is a popular implementation of Service Oriented Architectures (SOA), have been outstanding for years as the leading technology in the Distributed Computing world reached its third generation. The importance of web services facilitates the need in now a day’s Mobile phones to have the ability of consuming and accessing Web Services. Web Services is nothing but an implementation of the Service Oriented Architecture as it in evolves distributed systems, describes the general architecture and some standards involved in it. These services utilize SOAP protocol.
Earlier we have expenses tracker application with local database, in this project Developing Google Android Mobile Clients for Web Services [4], users can save his personal data on his mobile. If the mobile crashes or mobile lost there is no way to take the back up of the data. So if the mobile data is saved in some centralized location the user can save or backup his data even if the mobile is lost or crashed. This is not the only one advantage of this, as we have the centralized database, the development architecture is different. Here we are maintaining SOA, which means once if we have a web service in remote server with centralized database then we can use the same web service for different clients either it may be Android, iPhone, Blackberry, Windows phone, Bada, Java phones, Symbian phones, etc. Different clients can use the common web service to save or retrieve the data. We can also take backup/restore the database from database end. For this to implement the main resource needed is Internet Information Server (IIS) Web Server. For this SOA process the current database MS SQL Server database can also be replaced by other databases like MySQL, Oracle, Postgre, etc.
Building an Android application that runs on mobile phones for tracking expenses. The application will store data locally and as well as on the server using web services. Users can enter expenses using the app like name of the expense, category of the expense, amount spent, date, etc. Users can view expenses both in table form and in graph form. This application provides flexibility to users by calculating monthly, yearly and as well selected category wise budget. Many people are unaware of costs and waste scarce resources. Expenses tracker is the way to calculate the total costs of purchasing and utilization of the product and helps to control and reduce costs to plan for the future in regards to the budget. The main goal of implementing this project is to support Google Android mobile platform as client, thereby demonstrating its main features, design and architecture and illustrating the importance of Android mobile platform relationship with Web Services.
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TABLE OF CONTENTS
PAGE
ABSTRACT ...............................................................................................................................v
LIST OF TABLES ................................................................................................................. viii
LIST OF FIGURES ................................................................................................................. ix
ACKNOWLEDGEMENTS ..................................................................................................... xi
CHAPTER
1 INTRODUCTION .........................................................................................................1 1.1 Short Notes on Expense Tracker........................................................................1 1.2 System Analysis .................................................................................................1 1.3 Existing System .................................................................................................2 1.4 Proposed System ................................................................................................2 1.5 Characteristics and Key Features of the Proposed System ................................3
2 LITERATURE ...............................................................................................................4 2.1 Mobile Platform .................................................................................................4
2.1.1 What is Android ....................................................................................... 4 2.1.2 Android Components ............................................................................... 4 2.1.3 Activity .................................................................................................... 4 2.1.4 Services .................................................................................................... 4 2.1.5 Intents ....................................................................................................... 5 2.1.6 Content Providers..................................................................................... 5 2.1.7 Broadcast Receivers ................................................................................. 5 2.1.8 Applications ............................................................................................. 6 2.1.9 Tools ........................................................................................................ 6
2.2 Android Application Features ............................................................................6 2.3 Setting Up the Android Environment ................................................................7
2.3.1 Using DDMS ........................................................................................... 7 2.3.2 Installing the ADT Plug-In for Eclipse .................................................... 7 2.3.3 Creating an AVD ..................................................................................... 7
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2.3.4 Steps to Install the Android Environment in Eclipse ............................... 8 2.4 Android Versions and Project Directory Structure ............................................8
2.4.1 Android Versions ..................................................................................... 9 2.4.2 Android Project Directory Structure ........................................................ 9 2.4.3 Units of Measurements .......................................................................... 10 2.4.4 Important Attributes of XML Views ..................................................... 10
3 DESIGN SPECIFICATION ........................................................................................11 3.1 Use Case Diagrams ..........................................................................................11
3.1.1 Expenses Use Case Diagram ................................................................. 11 3.1.2 Show Expense Use Case Diagram ......................................................... 12
3.2 Expenses Class Diagram ..................................................................................12 3.3 Expenses Sequence Diagram ...........................................................................13 3.4 Expenses Collaboration Diagram ....................................................................14 3.5 Data Flow Diagram ..........................................................................................15 3.6 Tabular Form of Representation of the Database Fields .................................15
4 IMPLEMENTATION ..................................................................................................19 4.1 System Requirements.......................................................................................19 4.2 Implementation of the Expense Tracker ..........................................................19 4.3 Usage of Expense Tracker Application with Web Services ............................20 4.4 Steps to Configure the Project .........................................................................21 4.5 Web Services Overview ...................................................................................21
4.5.1 Main Features of Web Services ............................................................. 22 4.5.2 Major Advantages and Known Challenges of Web Services ................ 22 4.5.3 Major Organizational Challenges Addressed by Web Services ............ 23
4.6 Android Application Development by Consuming .Net Web Services ..........23 4.6.1 Requesting SOAP Web Service ............................................................. 23 4.6.2 Calling the Service ................................................................................. 24
5 GRAPHICAL USER INTERFACE ............................................................................25 6 DISCUSSION ..............................................................................................................33
6.1 Future Enhancements .......................................................................................33 6.2 Conclusion .......................................................................................................33
BIBLIOGRAPHY ....................................................................................................................34
viii
LIST OF TABLES
PAGE
Table 3.1. Function Names: Expenses Table ...........................................................................17 Table 3.2. Function Name: Category Table .............................................................................18
ix
LIST OF FIGURES
PAGE
Figure 1.1. Existing system architecture. ...................................................................................2 Figure 1.2. Proposed system architecture. .................................................................................3 Figure 3.1. Use case diagram for creating expenses. ...............................................................11 Figure 3.2. Show expense use case diagram. ...........................................................................13 Figure 3.3. Expenses class diagram. ........................................................................................14 Figure 3.4. Expenses sequence diagram. .................................................................................14 Figure 3.5. Expenses collaboration diagram. ...........................................................................15 Figure 3.6. Data flow diagram for the application. ..................................................................16 Figure 5.1. Homepage. .............................................................................................................25 Figure 5.2. Creating a new expense and entering the details for the expense. ........................25 Figure 5.3. Setting up the date. ................................................................................................26 Figure 5.4. Newly created expense is saved successfully. .......................................................26 Figure 5.5. Displaying the created expenses in table and R-graph form. ................................27 Figure 5.6. Listing the expenses in table form. ........................................................................27 Figure 5.7. Displaying expenses for whole year. .....................................................................27 Figure 5.8. Displays amount spent in each month. ..................................................................27 Figure 5.9. Total expenditure for the selected month. .............................................................28 Figure 5.10. Select a particular month to display monthly expenses. ......................................28 Figure 5.11. Displaying expense categories and amount spent in a month. ............................28 Figure 5.12. Category wise listing the expenses. .....................................................................28 Figure 5.13. All expenses under office supplies category is shown. .......................................29 Figure 5.14. Graphical representation for a selected category. ................................................29 Figure 5.15. Graph for selected category. ................................................................................29 Figure 5.16. Graph for expenses spent throughout whole year. ..............................................29 Figure 5.17. Retrieving the information stored in the database. ..............................................30 Figure 5.18. Hosting the web service in the remote server using IIS. .....................................30 Figure 5.19. Application is loaded using the web service which is hosted in the server. ........31
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Figure 5.20. Inserting a new category by running the application locally. ..............................31 Figure 5.21. Displays all the expenses for whole year. ...........................................................32 Figure 5.22. All the expenses saved throughout the whole year are displayed. ......................32
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ACKNOWLEDGEMENTS
I would like to express my heartfelt gratitude to Dr. Joseph Lewis and Carl Eckberg
for giving me the opportunity to work on this project and for providing constant support and
motivation. I would also like to thank Professor Moon Song for serving on my thesis
committee.
I would also like to thank my dad, mom, grandparents, and my entire family for the
sacrifices they made to help me attend graduate school. I am very grateful for all their
support and motivation that they have provided for the past two years.
1
CHAPTER 1
INTRODUCTION
1.1 SHORT NOTES ON EXPENSE TRACKER Suppose consider a person who doesn’t possess a simple and easy mechanism by
which he can control the flow of the amount spent on the expenses per month or per year.
This application provides the most important feature by which the above mentioned problem
can be addressed i.e., it allows the users to keep track of their money monthly and yearly
wise which in turn serves best to get an idea of all the different kinds of expenses. It will
allow users to create new expense, show expense details, and add categories to the database.
This application allows you to track money spent on all your daily or monthly or annual
expenses. It provides a quick way to track expense, income and bookkeeping purposes.
Expenses Tracker is great application for managing your expenses and it is a simple way to
manage your personal finances. Internet Access is used to save and retrieve expenses from
Mobile. We can take database backup and restore.
1.2 SYSTEM ANALYSIS As discussed in the abstract the existing system has no security in terms of
maintaining the database or to take the backup. There is no centralized protection to the
database. If the mobile crashes or mobile lost there is no way to take the back up of the data.
Some of the features that expenses tracker posses are:
1. Expenses Tracker is a simple and friendly and intuitive expenses tracking application which focuses more on helping manage individuals finance.
2. It easily creates your own category and sub-category of the expenses eventually which helps in Organizing your categories
3. This application also provides an easy way to Generate reports which Tracks and analyzes spending with customizable reports.
You can use Expenses Tracker to:
• track personal expenses
• track travel expenses
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• track entertainment expenses
• track income
• track club collection
• track project expenses
• track bills
• track investment portfolio
1.3 EXISTING SYSTEM In the current system configuration, data will be stored inside the Mobile phone in
SQLite Database (see Figure 1.1). If we want to save the data in a common place, i.e.,
Remote Server until now there is no easy mechanism to implement this. The need for storing
information in remote server exists because even if the mobile is lost or stolen you can get
back all the expenses data stored inside the phone. The idea of storing information in remote
server is implemented using Web Services which can save the data in the Remote database
like SQL Server.
Figure 1.1. Existing system architecture.
1.4 PROPOSED SYSTEM The proposed mobile application is completed based on Service Oriented
Architecture (SOA) where we have thin clients like Android Phones, iPhones, etc. Services
are self contained and communicate using messages like xml. They are cross platform,
asynchronous, reliable and secured. SOA is an architectural style for building business
applications using loosely coupled services which act like black boxes and can be
Android phone SQLite
3
orchestrated to achieve a specific functionality by linking together which you can see in
Figure 1.2. Once we have a web service in remote server with centralized database then we
can use the same web service for different clients either it may be Android, iPhone,
Blackberry, Windows phone, Bada, Java phones, Symbian phones, etc. Different clients can
use the common web service to save or retrieve the data. We can also take backup/restore the
database from database end.
Figure 1.2. Proposed system architecture.
1.5 CHARACTERISTICS AND KEY FEATURES OF THE PROPOSED SYSTEM
Characteristics and key features of the proposed system are as described below:
For Organizations: It is a quick handy way to track expense, income, mileage, sales,
receipts for tax reimbursement and bookkeeping purposes.
For Day to Day Life: It helps in monitoring cash flow, balance available in a
particular month from anywhere and at any time.
User-Extendable Database: User can add income/expense categories. We can take
database backup and restore.
Android phone Web Service Database
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CHAPTER 2
LITERATURE
2.1 MOBILE PLATFORM Mobile platform is an operating system for mobile devices. Some of the mobile
devices operating systems are iOS, Bada, Android, Windows, and Blackberry, etc.
2.1.1 What is Android Android is a software pile for mobile devices which includes an operating system,
middleware components and other key applications. The Android SDK facilitates the APIs
and tools needed to start developing applications on the Android platform. For Developing
applications in Android the programming language used is Java programming language.
2.1.2 Android Components These are some of the Android components which are the major means by which
Android application runs successfully without any interruptions.
2.1.3 Activity Android activity is represented by each individual screen within an Android
application. User can interact with activity by performing some actions which involves visual
components. Example of an activity can be considered as a single webpage in a website.
Each activity performs its operations independently of one another and all the activities in the
application are an extension from the activity class.
2.1.4 Services Service is another component in Android application which performs its actions in the
background to accomplish actions which take long time to run or remote processes tasks.
Service is a component which does not possess user interface. Consider an example where
service can play music in the background when the user is performing some operation in
other application like checking an email or texting a message using SMS application or
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retrieve some information from the network without interrupting user’s actions within an
activity
2.1.5 Intents Intent is an application which initiates the message passing between the activities.
Using intents messages can be broadcasted throughout the system or if it can also pass
messages to a target activity or service, which states intended action requested by the user or
activity. Specifying an Intent-filter allows a user to state how a particular activity in an
application should be called.
2.1.6 Content Providers A content provider is a component which maintains a collective group of application
data. All the application information or data can be stored in a SQLite database or file
system, on remote web servers or on any storage location where the application can access
the data. Using the content provider, other applications can process its queries and other
related activities. This component mostly behaves like a database where users are given
flexibility to edit its contents, query information needed, delete some data when not needed.
The only difference between database and content provider is that using content provider
users can store its data in different ways.
2.1.7 Broadcast Receivers This component responds to system wide broadcast declarations. Any application
which needs to receive or respond to global activities like SMS application, receiving an
incoming call, it should have been registered as a broadcast receiver. Most of broadcasts
come from the system for example, we can consider a broadcast statement like when battery
is low it shows red colored battery symbol in the phone, when screen lock button is pressed
the display will be turned off, when SMS is received its shows a message symbol at the top
of the notification bar. Broadcast receivers doesn’t possess user interface for broadcasting
notifications instead they alert the users by showing the status of the application in the
notification bar.
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2.1.8 Applications All the Android packages by default comes with a bunch of core applications which
includes an SMS application, Email application, calendar, maps, browser, contacts, GPS and
others. All these applications are developed using the Java programming language.
2.1.9 Tools The Android SDK is Software Development Kit which allows developers to develop
mobile applications in Android platform. Generally these tools are categorized into two
groups, they are SDK tools and platform tools. Among these SDK tools are independent of
the platform and these are mandatory for any mobile application which are developed in
Android platform. The second most common tools are Platform tools which are modified or
personalized to provide support to the latest Android platform features.
2.2 ANDROID APPLICATION FEATURES Android offers several application features out of which the following mentioned
features are the most effective and useful characteristics of Android applications:
• The Dalvik Virtual Machine has been upgraded to improve developing mobile devices applications framework enabling reuse and replacement of components.
• GSM the Global System for mobile communications kind of telephony has been introduced.
• A productive application framework has been developed which enables the application components to be reused and replaced.
• Open source web kit has been integrated in the browser.
• Custom 2D and 3D graphics libraries came to the market which are based on Open GL specification.
• Structured data storage is supported by using SQLite database.
• All the audio, video and image formats are supported in the new Android versions like MPEG, MP3, JPG, GIF, PNG and ING.
• Hardware supportive environment like Wifi, 3G, 4G, EDGE connectivity and Bluetooth are improved in the Android platform.
• Development environment has been made popular by introducing device emulator feature Camera, GPS, compass, and accelerometer (hardware dependent).
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• All other important features include accelerometer, camera, GPS, several different tools which helps in debugging the application, memory management and performance monitoring.
2.3 SETTING UP THE ANDROID ENVIRONMENT Android Development environment can be set in any machine using Eclipse IDE. To
develop an Android application the following tools must be installed in Eclipse [1].
2.3.1 Using DDMS Android ships with a debugging tool called the Dalvik Debug Monitor Server
(DDMS), which provides port-forwarding services, screen capture on the device, thread and
heap information on the device, log cat, process, and radio state information, incoming call
and SMS spoofing, location data spoofing, and more.
2.3.2 Installing the ADT Plug-In for Eclipse To install the ADT plug-in in Eclipse we need to click on Help button at the top of the
eclipse window then select Install New Software [1]:
• Click on add button in the Available Software dialog box.
• In the next dialog box enter the name for remote site for example ADT plug-in the “Name” field.
• Need to enter this URL in the Location field: https://dl-ssl.google.com/android/eclipse.
• Once this is done you should be able to see Developer Tools added in the list under the Available Software view. Click next by checking the box next to the Developer Tools.
• In the Installation progress dialog box you should see the Android DDMS and Android Development Tools features. Read and accept the license agreement, later install all other dependencies by clicking Finish button. Once installation is done restart Eclipse.
• Configure the ADT Plug-in by going into ADT preferences tab in Eclipse and browse to the Android SDK directory then click apply and OK.
2.3.3 Creating an AVD To configure the real world devices in an Android Emulator this Android Virtual
Device (AVD) is used. To run the emulator and display Android device in that we need to
create an AVD in the Eclipse [2].
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The following steps must be followed to create an AVD from Eclipse:
• Open Eclipse and go to Window toolbar and click on Android SDK and AVD Manager.
• A list of already existing AVDs will be shown under the Virtual Devices panel. Select the New button to create a new AVD.
• To create a new AVD some of the details must be given like name of the AVD, intended target platform, the size of the SD card and select HVGA as default skin.
• While defining a target for the AVD make sure that the application’s Build Target API level should match with compiling application API.
• After clicking on create AVD don’t forget to enable the Internet access permission to the mobile application that you are working on.
2.3.4 Steps to Install the Android Environment in Eclipse
The following steps describe the procedure to install Android SDK and ADT plug in
in the Eclipse IDE which enables users to view the Android applications in an emulator from
the machine:
1. Download and Install Java Platform (JDK)
2. Download Eclipse IDE for Java Developers
3. Download the Android SDK Tools
4. Update the Android SDK
5. Configure Eclipse with Android Development Tools (ADT) and Update the Developer Tools
6. Update the Android SDK path by selecting windows preferences and add SDK path in Eclipse
7. Create Android Virtual Device (AVD) or Emulator
8. Set the Class path for Android SDK and Java
2.4 ANDROID VERSIONS AND PROJECT DIRECTORY STRUCTURE
The following sections describe the current and the upcoming versions of Android
software. Also Android project directory structure and Android attributes of the XML view
are also described.
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2.4.1 Android Versions Google introduced several different versions of Android Operating System. These are
some of the android versions which evolved as updates to the previous versions.
2.0/2.1 (Eclair), which enhanced the user interface and brought into existence a new
feature HTML5, W3C Geolocation API and Exchange ActiveSync 2.5 support
2.2 (Froyo), introduced speed improvements with JIT optimization and the Chrome
V8 JavaScript engine, and added Wi-Fi hotspot tethering and Adobe Flash support
2.3 (Gingerbread), which refined the user interface, improved the soft keyboard and
copy/paste features, and added support for Near Field Communication [3].
3.0/3.1 (Honeycomb), a tablet-oriented release which supports larger screen devices
and introduces many new user interface features, and supports multicore processors and
hardware acceleration for graphics.
3.2 (Honeycomb), which is similar to 3.1 but optimized for 7-inch tablets.
4.0 (Ice Cream Sandwich), a combination of Gingerbread and Honeycomb into a
“cohesive whole.” It was announced on May 10, 2011 at Google I/O that it will be released
in Q4 2011.
2.4.2 Android Project Directory Structure SRC is folder under com.packagename in filename.java file which consists of all the
source code for the particular project
Gen is a folder under com.packagename in R.java file
Assets – Assets is a directory in Android application which consists of the assets
extensively used by some of the applications like Databases, Text files and HTML etc
Res – Resource is a folder which contains all the resources used in the application
such as layout, raw, menu, anim, values, color, xml, drawable-hdpi, drawable-mdpi, and
drawable-ldpi.
Androidmanifest.xml: This is a manifest file which consists of Package name, version
code, version name, application image, name of the application, activity information, intent
filter, Android: minSdkVersion and permissions [4].
XML File (UI of Android Activity) <?xml version=“1.0” encoding=“utf-8”?> <LinearLayout xmlns:android=“http://schemas.android.com/apk/res/android”
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android:orientation=“vertical” android:layout_width=“fill_parent” android:layout_height=“fill_parent”> <TextView
android:text=“row one” android:textSize=“15sp” android:layout_width=“fill_parent” android:layout_height=“wrap_content”
/> </LinearLayout>
2.4.3 Units of Measurements Most of the web pages are designed in pixels but when pixel ratio is used there are
some problems with the increased screen resolution. In order to avoid this problem android
supports the following units of measurement.
DP or Dip: Dip is abbreviated as Density Independent pixel where 160dp is
equivalent to one inch of physical screen size.
SP: SP is abbreviated as the Scale Independent Pixel which is recommended for
specifying font sizes in the Android application.
2.4.4 Important Attributes of XML Views These are some of the most widely used attributes in Android applications which
helps in better XML views of a screen in the application.
xmlns:android: This is an XML namespace declaration that tells the Android tools
that you are going to refer to common attributes defined in the Android namespace. The
outermost tag in every Android layout file must have this attribute.
android:id: This Attribute can be used as the assigned ID which behaves like a
reference View from the source code or from other XML resource declarations.
android:layout_width: This attribute defines how much of the available width on the
screen this View should consume
android:layout_height: The attribute layout_height refers to the available screen
height for the application.
android:text: This particular attribute sets the text alignment in which Text View of
the application should be.
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CHAPTER 3
DESIGN SPECIFICATION
3.1 USE CASE DIAGRAMS The architecture of the application is explained using Unified Modeling Language
diagrams.
Unified Modeling Language (UML) [5] provides IT professionals with a common
design format to build and develop computer applications using the design view of the
application. Use Case diagram in Figure 3.1 demonstrates the functionality of each individual
unit in the system. These diagrams help in better visualization of the functional requirements
which includes the relationship between actors and the use cases.
Figure 3.1. Use case diagram for creating expenses.
3.1.1 Expenses Use Case Diagram This is the use case diagram for Expenses Tracker application. Here user is provided
with three different options of which are create new expense, show expense and add
category. When user selects create new expense it will allow them to create a new expense
like laptop, furniture, books, insurance, etc. Show Expense is the field which displays the
Show Expenses
Data Base
Create New Expenses
Add Category
User
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output of the selected categories and expenses both in Table and R-Graph form, there is a
database connected to the show expense field so that when ever user requests for some
information the request will be sent to the database, query will be processed and then later it
sends the response back to the application. Add Category is the field which will allow users
to create a new category for the expenses like office supplies, leasing, business loans,
transportation, etc.
3.1.2 Show Expense Use Case Diagram In Figure 3.2 Use Case Diagram for Show Expenses Field is shown. When user wants
to see the output of the created expenses through whole year or for a particular month this
field will provide the necessary information. In the Table form of the display there are four
sub sections namely Expense list, Total Expense per month, Expense per selected month,
Expense List Category which helps in displaying the output monthly expenses spent, yearly
expenses created and category based expenses spent. In the similar way R-graph also
displays all the information from the database in the graphical form so that it will be easy for
users to keep track of the money flow throughout year or for a particular month as well.
3.2 EXPENSES CLASS DIAGRAM Figure 3.3 explains the class diagram for the Expense Tracker application. It consists
of four classes namely Mobile Application, Web service, Search criteria and Database. Each
one of these classes has their own role in contributing to the project work flow:
1. Mobile application class consists of methods like add category, create new expense and search method which invokes an object in the Search Class when user requests for some information.
2. Web service class consists of methods like getExpensedata, getCategoryData, InsertExpenseData and insertCategoryData. All of the user requests will be received by web service using SOAP protocol it forwards the request to the Database and receives the response back from the database and which gives the resultant information back to the mobile application.
3. Search class consists of only two methods Request and Response but these methods play a major role in transferring the information from the application to the database and back from the database to the application which uses web service to search for the information in the database.
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Figure 3.2. Show expense use case diagram.
4. Database is the class which consists of methods like getData and insertData which helps in receiving the information from the application, stores the information in the database and returns back the information when user request is made.
3.3 EXPENSES SEQUENCE DIAGRAM The Sequence diagram for Expenses Tracker application is explained in Figure 3.4.
Here whenever user requests to creates a new expense, add categories those details will be
inserted from the application into the database, whereas the database stores all the expense
details created by the user, once the request is processed it returns back the desired output to
the application. In the application User Interface, the results will be displayed both in
Table form and R-Graph form.
Tables
R-Graph
Total Expense Per Month
Show Expense
Expense List
User
DataBase
Expense Per Selected Month
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Figure 3.3. Expenses class diagram.
Figure 3.4. Expenses sequence diagram.
3.4 EXPENSES COLLABORATION DIAGRAM Figure 3.5 is the Collaboration diagram which depicts that whenever user enters
new expenses details by adding categories and expenses, the application stores the
information in the database and returns the expense details to the application. User will
be able to see the output in the application where the information is displayed in Table and
R-Graph form.
User: Application DataBase
Creates new Expenses and adding categories and inserting detailsStores user expense details in the database
Gives the details of the Expenses
Shows the details to the user in the form of Tables and R-Graph
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Figure 3.5. Expenses collaboration diagram.
3.5 DATA FLOW DIAGRAM In Figure 3.6 Data Flow Diagram for the Expenses Tracker application is shown. The
application starts with three fields like Create New Expenses, Show Expenses and Add
Category. Suppose a user wants to create a new expense for this month he can do that using
this field by entering the details. He can also add new Categories to the application using the
field add category which prompts the user to enter desired category name. To retrieve back
the stored expenses from the database user can select show expenses category by which he
can view the result in both Table form and R-Graph format.
3.6 TABULAR FORM OF REPRESENTATION OF THE DATABASE FIELDS
Table 3.1 shows the functionality that allows the user to create New Expenses and to
view the details of the Expenses. Table 3.2 shows the functionality that allows the user to add
the Category.
User: Application
DataBase
1: Creates new Expenses and adding categories and inserting details
2: Stores user expense details in the database
3: Gives the details of the Expenses
4: Shows the details to the user in the form of Tables and R-Graph
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Figure 3.6. Data flow diagram for the application.
Start
Add Category
Create New Expenses
Show Expenses
Shows Tables and R-Graphs Enter the details of
Expenses
Enter the Category Name
Stop
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xpec
ted
to e
nter
the
Dat
e In
put
Yes
(1
) Can
not b
e nu
ll.
5 A
mou
nt
Use
r is e
xpec
ted
to e
nter
the
Am
ount
Y
es
(1) C
anno
t be
null.
U
ser
Inte
ract
ion
and
Syst
em In
tera
ctio
n Fi
elds
O
pera
tion
Use
r In
tera
ctio
n Sy
stem
Inte
ract
ion
Err
or/W
arni
ng?
Mes
sage
N
ew
(1) U
ser w
ill b
e ab
le to
read
the
new
Ex
pens
es d
etai
ls.
(1) S
yste
m sh
ould
gen
erat
e ne
w
Acc
ount
. (2
) It s
houl
d cr
eate
a n
ew re
cord
and
sa
ve it
in d
atab
ase
with
a su
cces
s m
essa
ge a
nd S
ave
the
Cre
ated
det
ails
.
“Rec
ord
save
d su
cces
sful
ly.”
Mod
ify
(1) U
ser w
ill b
e ab
le to
mod
ify th
e de
tails
usi
ng th
is o
ptio
n.
(1) S
yste
m sh
ould
upd
ate
mod
ified
ac
coun
t in
data
base
with
succ
ess
mes
sage
. (2
) Upd
ate
the
Mod
ified
det
ails
.
“Rec
ord
save
d su
cces
sful
ly.”
Get
AllE
xpen
seD
ata
(1) U
ser w
ill b
e ab
le to
get
the
Expe
nse
Dat
a
Get
Expe
nseD
ataF
or
Cat
egor
yNam
e (1
) Use
r will
be
able
to g
et th
e Ex
pens
e D
ata
for t
he C
ateg
oryN
ame
Get
Expe
nseD
ataF
or
Sele
cted
Mot
hWith
Tota
l (1
) Use
r will
be
able
to g
et th
e Ex
pens
e D
ata
for t
he se
lect
ed m
onth
with
tota
l.
18
18
Tab
le 3
.2. F
unct
ion
Nam
e: C
ateg
ory
Tab
le
Mai
n Fu
nctio
nal A
reas
Sr N
o.
Nam
e of
Attr
ibut
e D
escr
iptio
n M
anda
tory
V
alid
atio
ns
1 C
ateg
ory
ID
Use
r is e
xpec
ted
to e
nter
the
Cat
egor
y ID
Y
es
(1) C
anno
t be
null.
2
Cat
egor
y na
me
Use
r is e
xpec
ted
to e
nter
the
Cat
egor
y na
me
Yes
(1
) Can
not b
e nu
ll.
Use
r In
tera
ctio
n an
d Sy
stem
Inte
ract
ion
Ope
ratio
n U
ser
Inte
ract
ion
Syst
em In
tera
ctio
n E
rror
/War
ning
M
essa
ge
New
(1
) Use
r will
be
able
to re
ad th
e ne
w
mob
ile fe
atur
es.
(1) S
yste
m sh
ould
gen
erat
e a
new
A
ccou
nt.
(2) I
t sho
uld
crea
te a
new
reco
rd a
nd
save
it in
the
data
base
with
the
succ
ess m
essa
ge.
(3) S
ave
the
“Mod
ified
” an
d “C
reat
ed”
deta
ils.
“Rec
ord
succ
essf
ully
save
d.”
Mod
ify
(1) U
ser w
ill b
e ab
le to
mod
ify th
e de
tails
us
ing
this
opt
ion.
(1
) It s
houl
d up
date
mod
ified
acc
ount
in
dat
abas
e w
ith su
cces
s mes
sage
. (2
) Upd
ate
Mod
ified
det
ails
.
“Rec
ord
succ
essf
ully
save
d.”
Get
AllC
ateg
oryD
ata
(1) U
ser w
ill b
e ab
le to
get
all
the
cate
gory
dat
a.
19
CHAPTER 4
IMPLEMENTATION
4.1 SYSTEM REQUIREMENTS These are minimum system and software requirements which serve best in
developing Android applications using the Android SDK.
Supported operating systems include:
• Windows Vista or XP (32 bit or 64 bit)
• OS: Android version 2.2 and 2.3
Supported development environments:
• Eclipse 3.5 (Galileo)
• Android SDK Tool
• Eclipse ADT
• USB Driver for Windows (to check the output in Android Phone)
Hardware requirements include:
• Android Mobile or Android Emulator
4.2 IMPLEMENTATION OF THE EXPENSE TRACKER The Expense Tracker application is implemented with the .Net language web service
using KSOAP2 Library in Android. For information storage and retrieval of the data, used
the SQL Server 2008 database to create tables maintain data in the database. This application
needs Internet connectivity in the Mobile phones to work better with web services. Consider
a user needs to retrieve some information from the application then the user request will
initiate a query inside the mobile application, which in turn sends a request to the web
services using Request and Response methods in the SOAP protocol those requests will be
processed and when the requested action is completed it sends a response back to the mobile
application. For example suppose user requested to create a new category or a new expense
under a particular category, the request is sent to the mobile application first and then to the
remote database using the web service calls, after querying the input the web server
responses back with the message saying “Expenses created successfully” (row inserted). In
20
the same way if we consider an example to Get All the Categories created throughout the
whole year the application returns all the categories in the database using a web service that
is hosted in Internet Information Services (IIS).
4.3 USAGE OF EXPENSE TRACKER APPLICATION WITH WEB SERVICES
Expense App Communicates with the server using the web service URL which is
hosted in the web service (IIS) at remote location. We can add this URL at only one location
i.e., in values/strings.xml file.
The communication is achieved using a KSOAP2 library. Using KSOAP2 the
Android app gives SOAP requests to the web server, the web server responses back with the
data for the query to the mobile application. The ksoap2 is an efficient and lightweight SOAP
library for the Android platform.
Most of the kSOAP2 [6] library has been tested keeping in mind about the Android
platform .This library also has lots of upgrades which adds more features and enhancements
and continuously works on fixing bugs and contributions. Whenever new features are
included in the library they release that software regularly.
The web server communicates with the databases like MS SQL Server, MySQL, and
Oracle, etc. Currently in this application we are using MS SQL Server, in future if we want to
change the database we can change the database with few changes in the web service. The
database is maintained centrally where we can take backups and restore it.
To construct this complete architecture of the application the following software’s
needs to be installed:
1. Install the Java JDK environment
2. Download Eclipse and update with Android Debugging Tool
3. Download and update Android SDK (Update Android SDK by clicking sdkmanager.exe inside SDK folder)
4. Install SQL Server 2008
5. Install Visual Studio 2010
6. Install the IIS Server
7. Host the web service in IIS
8. Refer the URL in the Expenses App
21
9. Consume the web service using KSOAP2 methods inside the expenses Tracker mobile application.
4.4 STEPS TO CONFIGURE THE PROJECT To set up the Development environment for this application. The following
software’s and tools must be installed:
1. Create a database using SQL server 2008 or other with the name Expenses and in the database create two new tables namely Category table and Expenses table as shown in the Figure 5.17 (see Chapter 5, page 30).
2. Use Visual Studio 2010 to Open the Web Service Project and the database connection string values should be set in Data Access Layer (DAL) for this project there are two DAL layers which are Expenses DAL and Category DAL. The database connection string values can be given using connection string method in which data source, catalog, and User Id and password fields should be set.
3. Host the Web Service using Internet Information Services in Windows 7 or Windows XP platform.
4. In the Android Application, navigate to res/values/string.xml file and give the URL of the hosted web service. Example:
<string name=“URL”>http://192.168.1.2/Expenses/ExpenseWebService.asmx</string>
5. Right click on the Expenses project, click on properties, then navigate to Java Build Path and add the following two jar files by clicking on Add External JAR button.
Android Plot jar file and ksoap2 jar file which is present in External JAR folder inside the project
6. Now users can insert some data into the category and expenses table using Android application or Web services local host, the data inserted into the application will be stored in the database and check the application using Android User Interface.
4.5 WEB SERVICES OVERVIEW The main purpose of Service Oriented architecture [7] is accessing services of
software components by heterogeneous consumers in the Internet. There are many other
models other than SOA, which are strongly related to enterprise, where as SOA mainly deals
with integrating applications and also departments for the company [8].
Recent technologies like COBRA, MOM, .NET, J2EE can also be used with SOA to
develop interface, which can deploy it on a server and be used by the client. Than any other
technology implemented by SOA model, Web Services has emerged as the best due to its
highest independence level. This is also for a reason, that Web Services is a self describing
22
application that projects the business logic over the Internet through programming interfaces
and also using Internet Protocols in order to invoke these services. From a functional point of
view, using web services is very beneficial as these enable application to application
communication and this is making it easier accessing applications from the devices over the
Internet, where as old traditional web based applications interact between the user and the
website. The base and purpose for choosing this is because of standard protocols and data
formatting.
4.5.1 Main Features of Web Services In web services all the data will be exchanged using XML format (extensible Markup
Language):
• The integration of the applications over the internet is supported in multiple platforms
• Web services are not language dependent, i.e., web services features can be utilized using any programming language.
• As Web services utilize standard protocols like HTTP it makes the application access all the resources easily through firewalls.
• It provides broad range of features, functionalities and clients which varies from a small request to complex requests or services.
• Almost all of the Platforms varying from .NET, J2EE and CORBA comfort deployment of Web Services.
• Any application which uses web services can dynamically invoke public and private registries using the standard protocols like UDDI and ebXML.
4.5.2 Major Advantages and Known Challenges of Web Services
The most important advantages and challenges of using web services in an
application are as follows:
• The application will be hosted in the remote server using web services there by increasing the feasibility and availability of the application from anywhere by anyone and from any device.
• Application will be implementing Service-based architecture which encourages intra-enterprise and inter-enterprise communication.
• Some of the organizations who require smoothness and flexibility in an application can utilize web services to support better inter application communication over the Internet.
23
• The most important benefit of using web services is that any new application can be merged with existing application to bestow with collective Web services.
4.5.3 Major Organizational Challenges Addressed by Web Services
Web services addresses the following challenges which are possessed by most of the
organizations in the recent times [9]:
• Security: Web services feature is utilized in almost all of the applications where information storage and retrieval communication should be achieved in remote applications. So highly secured protocol standards like HTTP, SSL, UDDI must be implemented which uses the most effective authentication and authorization mechanisms to encrypt the messages between the applications. Since most of the applications are open to public the best solution would be to include these security standards like SAML, XML Encryption, and XML Signature in applications.
• Distributed transactions: The developing environment should be tested and studied appropriately using these standard solutions so that the application environment can utilize the feature of distributed transactions within multiple resources.
• Quality of Service (QoS). For any kind of business critical application, quality of service of the application must be carefully examined by the service provider so that under peak load and unexpected conditions the applications performance and reliability should be stable. Application should be able to provide load balancing and fault tolerance even in unstable situations.
The Other kind of challenges like manageability and testing the applications in
different operating system environments and platforms are also addressed by Web services
deployment in an application.
4.6 ANDROID APPLICATION DEVELOPMENT BY CONSUMING .NET WEB SERVICES
Android Mobile application requests the web service with parameters, receiving the
response and parsing it to obtain data. We use KSOAP2 protocol to consume .Net Web
Services.
4.6.1 Requesting SOAP Web Service Web services process the inter communication between application and database
using SOAP protocol [10]. A SOAP protocol consist of three components under it namely
SOAP request/response, Header and Body.
24
SOAP Request/Response is sent as a SOAP Envelope which consists of a SOAP
Header and a SOAP Body.
SOAP Header: It is a component of the soap envelope which is optional and mostly
contains the information which is specific to the application. Example of such information in
soap header is the authentication mode which we specify for any application like read, write,
etc. It contains a SOAP Action which helps in identifying the required functions to be called
by the service.
SOAP Body: Soap body consists of the actual message which is sent to the service
and acknowledgment received from the service.
4.6.2 Calling the Service To call the SOAP [11] web service the following procedure must be applied.
First construct the SOAP envelope following the standards mentioned in the Soap
protocol.
As soon as the function is called the response will be in a String format. This
response message should be parsed again to extract the data which is the output of the
application.
25
CHAPTER 5
GRAPHICAL USER INTERFACE
I would like to present screenshots for the expenses tracker application. When the
Android application starts it will load the project and displays the home page. In the first
screen of the application the user is provided with three categories like create new expense,
show expense and add category. The sub categories under these sections are briefly depicted
in the following screenshots.
Figures 5.1 through 5.4 describe the sections that need to be filled to create a new
expense and once expenses is created it displays a message as expenses saved successfully.
Figure 5.1. Homepage. Figure 5.2. Creating a new expense
and entering the details for the expense.
26
Figure 5.3. Setting up the date. Figure 5.4. Newly created expense is
saved successfully.
Figures 5.5 through 5.13 demonstrate displaying the information in table view. In the
table view expenses per month, per year and for selected category are shown in the figures.
Figures 5.14 through 5.16 display the graphical representation of the data for a selected
category and for whole year. Figures 5.17 through 5.22 demonstrate setting up the database
and hosting the web service in the remote server to store and retrieve the data from the
server.
27
Figure 5.5. Displaying the created expenses in table and R-graph form.
Figure 5.6. Listing the expenses in table form.
Figure 5.7. Displaying expenses for whole year.
Figure 5.8. Displays amount spent in each month.
28
Figure 5.9. Total expenditure for the selected month.
Figure 5.10. Select a particular month to display monthly expenses.
Figure 5.11. Displaying expense categories and amount spent in a month.
Figure 5.12. Category wise listing the expenses.
29
Figure 5.13. All expenses under office supplies category is shown.
Figure 5.14. Graphical representation for a selected category.
Figure 5.15. Graph for selected category. Figure 5.16. Graph for expenses spent
throughout whole year.
30
Figure 5.17. Retrieving the information stored in the database.
Figure 5.18. Hosting the web service in the remote server using IIS.
31
Figure 5.19. Application is loaded using the web service which is hosted in the server.
Figure 5.20. Inserting a new category by running the application locally.
32
Figure 5.21. Displays all the expenses for whole year.
Figure 5.22. All the expenses saved throughout the whole year are displayed.
33
CHAPTER 6
DISCUSSION
6.1 FUTURE ENHANCEMENTS The current database MS SQL Server database can also be replaced by other open
source databases like MySQL, Oracle, Postgre, etc.
This project is developed as a beginner application for expenses tracker. It can be
further developed to provide a richer user interface. Expenses saved can be emailed to all
family members when needed.
In the application user interface there is no way to delete or modify expenses created.
This can also be implemented as future enhancement.
The web service feature implementation is shown only in Android phones which can
also extended to Blackberry phone, Windows phone, Symbian phones, iPhone, etc.
6.2 CONCLUSION The goal of implementing this project is to support Google Android mobile platform
as client, thereby demonstrating its main features, design and architecture and illustrating the
importance of Android mobile platform relationship with Web Services. By using Android
SDK and Eclipse IDE as the development environment the application is built keeping in
mind about the design standards and maintainability of the code.
This application is very simple to use and helpful to record all the expenses both
locally inside the phone and as well as on the server using web service.
34
BIBLIOGRAPHY
[1] Google Inc. ADT Plugin for Eclipse, 2011. http://developer.android.com/sdk/eclipse-adt.html, accessed Jun. 2011.
[2] Mihira Prasanna. Step by Step Procedure to Access Web Services from Android, 2010. http://www.codeproject.com/KB/android/webservice-from-android.aspx?display=Print, accessed Jun. 2011.
[3] Wikipedia. Android Operating System, 2011. http://en.wikipedia.org/wiki/Android_%28operating_system%29, accessed Jul. 2011.
[4] Vito Daniele. Developing Google Android Mobile Clients for Web Services, 2007. http://www.mobilab.unina.it/tesi/TESI_V.D.Cuccaro.pdf, accessed Jul. 2011.
[5] Donald Bell. An Introduction to the Unified Modeling Language, 2003. http://www.ibm.com/developerworks/rational/library/769.html, accessed Nov. 2011.
[6] Google Inc. kSOAP2-Android, 2011. http://code.google.com/p/ksoap2-android, accessed Jul. 2011.
[7] Object Innovations. Web Services Using C# and ASP.NET, Rev. 2.1, 2007. http://www.objectinnovations.com/CourseOutlines/418.html, accessed Aug. 2011.
[8] W3 Schools. Introduction to Web Services, 1999. http://www.w3schools.com/webservices/default.asp, accessed Oct. 2011.
[9] Rob Howard. Web Services with ASP.NET, 2001. http://msdn.microsoft.com/en-us/library/ms972326.aspx, accessed Oct. 2011.
[10] FeedBurner. All about Web Service in .Net, 2007. http://dotnetguts.blogspot.com/2007/09/all-about-web-service-in-net.html, accessed Jul. 2011.
[11] Sacoskun. Consuming .NET Web Services via kSOAP Library, 2010. http://www.sacoskun.com/2010/02/consuming-net-web-services-via-ksoap_07.html, accessed Oct. 2011.