Creating a Silverlight 4 based Application in VB.NET

Drawer Denso QR Bar Code in VB.NET Creating a Silverlight 4 based Application

Now let us get a quick hands-on experience with Visual Studio 2010, Expression Blend for .NET 4, and Silverlight by creating a simple but very powerful RIA. I will demonstrate the new capabilities of Silverlight 4, such as local file integration, with the new RichTextBox control, using the drag-and-drop functionality to insert JPG and PNG images within the RichTextBox control. You can start creating a Silverlight 4 project using Visual Studio 2010 or Expression Blend 4 RC. Here we will start by loading Visual Studio 2010 and creating a new Silverlight Application project with the name FirstApplication under C:\Users\<user name>\Documents\Books\Accelerated Silverlight 4\Source\ 1\Project1\ (see Figure 1-1).

Note As you see in Figure 1-1, three new project templates are introduced in Silverlight 4 and Visual Studio

2010. Silverlight Business Applications creates a sample WCF RIA Services based Lind of Business application. The sample project is created based on the Silverlight Navigation Application project template with WCF RIA services enabled and, by default, includes user authentication and registration services and Data Access helper classes. WCF RIA Services Class Library helps you to build reusable mid-tier and presentation-tier components and services to support multiple Silverlight-based RIAs. You can implement reusable user authentication, user registration, and data integration services using WCF RIA services class library. This template is available only if you have installed WCF RIA Services for Visual Studio 2010. Silverlight Unit Test Application helps to create a Silverlight unit test application to perform in-browser unit testing.

After you click OK, the next dialog allows you to create a new ASP.NET web site/web application project that hosts the Silverlight application (see Figure 1-2).

Figure 1-2. The New Silverlight Application dialog in Visual Studio 2010 For the purpose of the examples in this book, it does not matter if you use a web site or a web application project; however, web application projects are better for eventual deployment since they contain a project file suitable for MSBuild. Also, our project is going to be a simple demonstration project, so you do not need to select the Enable WCF RIA Services option. Click OK, and the Solution Explorer will show two projects: the Silverlight application (FirstApplication) and the web site supporting it (FirstApplication.Web). If you now build the application, the Silverlight application is built to a XAP file (with the naming convention <SilverlightApplicationName>.xap) that is automatically copied to the ClientBin folder within the web site. This XAP file contains the Silverlight application with start-up assemblies and resources and will be downloaded by the client when he or she visits the web site. If you now start the development server in Visual Studio (by pressing F5 or Ctrl+F5), you will see the Silverlight application start. If, however, you create a new web site in IIS, point the document root to FirstApplication.Web, and navigate to this site, you will get a 404 error when trying to load the Silverlight application in your browser. What s going on IIS 6 must know about the new file extension .xap. You accomplish this by adding a new MIME type to either the root of IIS or to the specific web site you created. The file extension is .xap and the MIME type is application/x-silverlight-app.

Note If you are using IIS 7, the XAP Silverlight package file type is already related to the application/xsilverlight-app MIME type. No additional steps are required.

Now let s take a look at Expression Blend 4 RC, a tool used to lay out user interface controls and create animations in WPF and Silverlight. You can open the current Silverlight Project in Expression Blend directly from the Visual Studio. Right-click on any XAML file of the project and select the option Open in Expression Blend.. . Alternatively, without closing Visual Studio, start Expression Blend, and from the Projects tab window, choose Open Project or go to File Open Project/Solution, and navigate to the solution file created in Visual Studio (in C:\Users\<user name>\Documents\Books\Accelerated Silverlight 4\Source\ 1\Project1\FirstApplication, if you used the same directory structure). The panes on the left in Expression Blend are devoted to managing project files (like the Solution Explorer in Visual Studio see Figure 1-3), triggers and events, and the visual states of the UserControl or control template. The panes on the right in Expression Blend are devoted to properties for various user interface elements; resources, which include style templates; and the Data pane, which supports sample data integration to view the application with sample data (without connecting to the live data) while you are in development mode.