1. Introduction

This is the first article of my series about deep dive into  ADO.NET Data Services. In this article I'm going to show you how to implement your own ADO.NET Data Services proxy with T4 templates.

Source code and database backup

2. Content

2.1 Problem

ADO.NET Data  Services is a very powerful toy, but as many other cool Microsoft technologies it needs some workarounds to become usable in the real world applications.

Most of the problems are connected with the auto generated proxy which is created after the addition of a service reference.

Introduction

Silverlight helps for creating Rich Internet Applications (RIAs). It runs in the context of the browser. There is an isolated area, called sandbox, which holds the Silverlight application. But why is it necessary to restrict the Silverlight applications in such a way? The answer of this question is pretty simple - because of the security. Running such applications locally is dangerous. They may damage your computer or your data. So, there is a necessity to somehow restrict them. Thus, a Silverlight application runs in the sandbox.

Short Introduction to the RIAs World

Nowadays the web space is full of different sites. Old-fashioned HTML is slowly being replaced by the new Rich Internet Applications (RIA). But why are they so popular? The passion of the RIA technology is that it tends to reform the static HTML sites in order to make them look more like Desktop applications.

Why Silverlight?

...

Since the first beta release of Silverlight 2 there was a lot of talk about controls such as TreeView, auto complete TextBox, WrapPanel, DockPanel etc, and because of the high demand some custom controls were created. Two weeks ago the Silverlight Toolkit was released and introduced the so long awaited controls. In this article we'll take a closer look at one of them - the TreeView.

Introduction

I believe that most of you are already familiar with the controls of this type either from their web or desktop experience with technologies such as WPF, WinForms or ASP.NET. But for those who are going to be introduced to this type of controls I'll give a short description: The TreeView is a control with tree structure which main purpose is to display hierarchical data in the form of nodes. Each node that has children can be collapsed and expanded.

In the article about the basic customizations of the DataGrid control we showed how to change the color of the rows and of the alternating rows, how to modify the headers' and the gridlines' visibility. But we haven't mentioned anything about how to change the look of the row when the mouse is over it or when it's selected. Let's take a look how we can achieve that.

Before starting

I won't start directly with the explanation of each thing and step we have to do. Instead I’ll start with a few common things. First there is no specific property for the color of the selected row, as RowBackground and AlternatingRowBackground and the only property that comes in hand is the RowStyle. The Target property of the style must be set to DataGridRow and the thing we have to customize is the Template property. I've tried to do this using the Expression Blend, but I didn’t find a way to get to this Template, so I had to disassemble the System.Windows.Controls.Data.dll and get the template from there. After that I modified what I needed in the VisualStudio.

1. Introduction

In the previous part of the article I described how to create a simple analog clock in Silverlight using pattern oriented approach. It was focused not so much on Silverlight but on the object oriented programming. In that part I will focus your attention on the process of improving the view (the clock face), making it much better and user-friendly. I will look at little more advance topics such as creating gradient brushes, creating custom figures, making transformations and of course adding movement and interactivity with animations.

So let’s roll up our sleeves and set to work.

Introduction

Note: this article is specific for Silverlight 2 Beta 2.

What is Internationalization and localization?

Localization and internationalization are the processes of making software capable to display content in different languages depending on the user preferences like described in Wikipedia.

It's a common scenario in business applications to support multiple languages. Development environments often automate the process of internationalizing an application. For example Visual Studio can create local resources for an ASP.NET Page or User Control automatically and in the ASP.NET web application the proper localized strings can be loaded automatically depending on the user preferences without the need for the developer to implement all this functionality.

What about Internationalization and localization in Silverlight?

I spent a few hours in Internet looking for some resources which cover this topic. So I'll try to summarize the process of building an international Silverlight application and will give some examples.

Using RESX files

Update: The demo, the source code and the code in the article are compatible with Silverlight 2 RTW. The only changes I made were to the object element in the host page.

This tip is about adjusting the size of the Silverlight object in the Html to the size of the content in our Silverlight application. The example I will use will manipulate only the height, because the width can be manipulated in analogical way.

Let's start with explanation of how we're going to access the Silverlight object in the HTML. We use the HtmlPage object in the codebehind. With its help we invoke a javascript function, which will deal with Silverlight object in the mark up:

private void ResizeSilverlightOnject( double height )

{

    HtmlPage.Window.Invoke( "ResizeObject", new object[] { height } );

}

Introduction

When it comes to making calls to a Web Service in Silverlight you have no other way, but to do it async. In many scenarios this could be a problem and especially when you use data binding.

The Problem

Consider you have a business objects Merchant and Sale and the Merchant has property Sales of type List as shown on the class diagram.

The sales are loaded from a web service.

Introduction

The need of selection is a pretty common thing. That made us think of a way to generalize the task and create a reusable class that can be used in more than one scenario. We put together a simple helper class that lets you handle selection easily.  The responsibilities of the class are:

• to keep only one item selected;
• to give you the index of the selected item;
• possibly to return a handle to the selected item

You can use the SelectionManager on any ObservableCollection of ISelectable objects. In fact you could use it on non-UI objects if you need to have one object in one state and the rest in another.