Microsoft Visual C# 2005 Express Edition: Build a Program Now! (38 page)

Add validations for user input, such as making

Add more information in the listing, such as consure the year of the car is not greater than the tact information

current year + 2

Make the URL clickable

Add pictures in the databases and on the form

Save an ad as a text file

Add a sold check mark

Add three forms to add data in the domain

tables (CarType, Make, Color)

In Summary…

That was a big chapter with a lot of material! Let’s review what you’ve learned. You were first introduced to databases and database concepts. You learned what constituted a database and what you usually find within a database. You learned about data integrity and how it is related to the primary key and the foreign key.

You then used Visual C# 2005 Express Edition to create a database and tables and then populated them with some initial data using various tools in Visual C# 2005 Express Edition. You implemented all of the foreign key relationships without leaving Visual Studio and validated them as well.

After entering your data manually, you learned how to allow a user to enter data more easily by developing a sample Car Tracker application that uses ADO.NET and databinding. Lastly, you learned about the new components of ADO.NET 2.0 and how, with little or no code, you can develop a fully working data-centric application. You’ve only been introduced to a brief part of ADO.NET, for it’s a vast subject. If you want to learn more, try looking at some code or samples on MSDN. A good place to begin is the 101 samples for Visual Studio 2005. Pay particular attention to the data access and Windows Forms samples. Here’s the link:
http://go.microsoft.com/fwlink/?linkid=51659.

In the next chapter, you will develop the final application of this book—the Weather Tracker application. You’ll learn new concepts such as deployment, consuming Web services, user settings, and much more in a complete application with all of the necessary validations.
Chapter 8: Managing the Data

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Build Your Own

Weather Tracker

Application Now!

Features of the Weather

You have now reached the last chapter of the book and have learned quite

Tracker Application, 166

a few new concepts along the way. In this chapter, you’ll dot the i’s and cross the t’s by developing a full application. You will be working with new pro
Creating the Application

cesses in this chapter, but you will also need to draw on what you’ve learned

User Interface, 168

in previous chapters to create the final product. You’ve been developing other applications throughout the book, but you may not have performed

Using Web Services, 181

all of the validations based on the steps or on my recommendation. You will CSX_Chapter

9

And Now, Just

put it all together with this application.

ClickOnce!, 204

This chapter uses a United States weather Web service. I

expect that this Web service will be available and func-

tion as described in this chapter. However, since this

Web service is on the Internet, it is possible that this

Web service might change or might not be available. If

you don’t have an Internet connection or if the weather

Web service is not available, the application will let you

know by displaying a message. If there are any changes

or corrections for this chapter (or in the book), they will

be collected and added to a Microsoft Knowledge Base

article. To view the list of known corrections for this

book, visit the following article:

http://support.microsoft.com/kb/905040/

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Features of the Weather Tracker Application

In this section, you’ll become acquainted with the features used to create version 1.0 of the Weather Tracker application. This application contains the following features
in version 1.0:

■ Starts and resides as an icon in the notification area of the Windows Taskbar

■ Configures optional user settings from the notification area icon in the context menu

■ Refreshes all weather data on demand from the context menu in the notification area

■ Uses a Web service for the data (weather)

■ Stores and persists user settings using XML

■ The application will minimize and not close when the user clicks the Close button in the title bar. The application will only close when the user selects Exit on the context menu.

■ Contains a splash screen on startup

■ Contains an About box from the context menu

■ Displays the current temperature using the weather icon as follows: a temperature above 100

degrees is displayed in red; any negative temperature is displayed in blue; normal temperature is displayed in black

The application will not contain the following features in version 1.0:

■ Will not work for more than one city at a time

■ No graphical gauge controls for wind, pressure, temperature, and so forth

■ Conversions between metric units and English units

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The High-Level Plan

For the Weather Tracker application, the user will briefly see the splash screen and then it will go directly to the notification area in the Windows Taskbar and display the current temperature. If the temperature is above 100 degrees F, the temperature will be displayed in red starting at 00. If the temperature is below 0 degrees F (negative degrees), the temperature will be displayed in blue. Otherwise, the temperature will be displayed in black. If a problem occurs, a red NA will show up in place of the temperature reading.

If the user right-clicks the icon in the notification area, it will open a context menu with choices to open the Main form and retrieve the current weather. The current weather will have an icon and provide all of the weather data that the Web service can provide. If the user selects Refresh Weather Info from the context menu from the notification area icon, it will automatically trigger a call to the weather Web service to update both types of weather data. This will be done asynchronously and will start by updating the current weather. If the user select Options from the context menu, an Options dialog box will be displayed. The user will be able to change the ZIP code where weather data should be retrieved. If the user selects About from the context menu, it will display an About dialog box.

In this chapter, I will use a different approach than used in previous chapters. As long as you are using the same components that I specify, you may personalize your application as far as size, color, and other attributes are concerned. I’ll also present my solution as well at different steps along the development; therefore, if you like what you’re seeing, you may proceed with your application from the companion content provided. I will also post a great deal of code and explain the sections that are linked to the features described above. To produce the application in this chapter, an incremental approach will be used in which you will implement one feature, integrate it with the rest of the application, and then test it. You will then move to the next feature until completion.

The Main form user interface (UI) will contain all of the weather information that you’ll display to the user. Refer to Figure 9-1 to see what the Main form will look like when finished.
Chapter 9: Build Your Own Weather Tracker Application Now!

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Creating the Application User Interface

The Main form user interface (UI) will contain all of the weather information that you’ll display to the user. Refer to Figure 9-1 to see what the Main form will look like when finished. At the moment, the form does not have any controls to display the weather information. As you learned in the last chapter, you will use databinding to bind the controls to the weather data. You’ll recall that when creating the data source, you had a choice of Database, Web Service, and Objects. In this application, you will use a Web service as a data source, and the fields you will display on the form will be data-bound to the Web service dataset.

Figure 9-1

View of the Main form in the Weather

Tracker application

TO CREATE A DATA SOURCE FOR A MAIN FORM CONTROL

Start Visual C# 2005 Express Edition and create a new Windows Application project. Name the appli1 cation
Weather Tracker
. In the Solution Explorer, rename Form1.cs to
Main.cs
. When you do this, Visual C# will ask you if you 2 want to perform a rename of all references to Form1 in the project. Click
Yes
to accept.

3 Using the Properties window, change the properties for the Main form using the following table:
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NOTE

Property

Value

All icons or image files in this chap-

ter will be located in a folder

Size:Width

550

named Images under the Chapter9

folder where you installed the com-

Size:Height

350

panion content. The default loca-

tion is \My Documents\Microsoft

BackColor

System:MenuHighlight

Press\VCS 2005 Express\.

ForeColor

Web:White

Font

Tahoma 8 Bold

Icon

Sun.ico

MinimizeBox

False

DoubleBuffered helps to reduce

MaximizeBox

False

or prevent flickering when the

form is redrawn. The form control

StartPosition

CenterScreen

is using a secondary buffer to

update the form’s graphics data,

FormBorderStyle

FixedDialog

whereby a quick write to the dis-

played surface memory is then

performed, reducing the chances

ShowInTaskBar

False

of flickering. If DoubleBuffered

is not enabled, then progressive

DoubleBuffered

True

redrawing of parts of the dis-

played form occurs, creating the

WindowState

Minimized

flickering.

Adding Notification Area Capabilities

Now that you have established the Main form, you’ll add the notification area capabilities. Let’s talk about terminology. If an application uses an icon located in the notification area (the area on the Windows Taskbar where the clock normally appears), this icon is called a notify icon and is implemented with a NotifyIcon control. The icon can have a context menu with different actions. Your icon will have a context menu with the following choices: About, Refresh Weather Info, Options, Open, and Exit.

Chapter 9: Build Your Own Weather Tracker Application Now!