I’m preparing to finish writing part of a chapter that talks about “The Road Ahead” for our soon to be released Silverlight 3 book so I had some help pulling together a summary of what people are asking for already as of today.  The following is just a snapshot but thought you might find it interesting if you didn’t have time to read the long forum list – The top 10 or so on the list all had multiple people requesting those items.

If taking the line number to the XAML file along with the position indicates it’s the DomainContext property that’s where it gets interesting.  I’ve been caught in this trap a few times as I scratch my head trying to figure out why it thinks DomainContext is invalid when I know for sure it is a valid property.  Unfortunately, there’s not an inner exception that you can get more details from so you are kind of stuck! So how do you get more info? 

The quickest way I have  found is simply remove the DomainContext property and set it via the code behind with some quick temporary code.  Then when you run the code in the debugger you will still get the exception but now will get a much clearer message typically than you got before.  In this case I was simply looking for a method that wasn’t exposed so the fix was easy now that I found the problem!

One quick search comparison that I think quickly highlight how they are going after the “Organized Search Experience” and the “Simplified Tasks and insight” as they put it.  First, I tried searching on my camera – Nikon D200 and here’s what I got for results from Google

That same search on Bing.com produced the following results

You can see on the left, a list of tasks or actions I can take.  So if I click on Lenses it takes me to search results for Lenses.

Bing.com is clearly a work in progress as some things still say Live or Virtual Earth but rebranding takes time.  I also hope that more work is done on the display of search results to use more of my display.  Currently Google, Bing and Yahoo all only utilize half of my wide screen monitors which is pretty crazy.  Maybe they could all spend some time on new layouts of results for wide screens!

Virtual Earth was also rebranded Bing Maps for Enterprise – more details on that here.  I’m still a little skeptical on that rebranding, but I will try to keep an open mind!   I can understand the consumer part of that being rebranded because it was already confusing being called Live Search Maps, but Virtual Earth had enterprise name recognition.

So go try Bing.com and let me know what you think of it!  I think it’s interesting to watch as the search game evolves – I still think there’s room for a lot more innovation that Google, Yahoo and Microsoft just don’t know what it is yet.  It will probably be some small startup that will have the magic invention!

The training kit is has presentations, labs and demos for the following topics

• C# 4.0
• Visual Basic 10
• F#
• Parallel Extensions
• Windows Communication Foundation
• Windows Workflow
• Windows Presentation Foundation
• ASP.NET 4
• Entity Framework
• ADO.NET Data Services
• Managed Extensibility Framework
• Visual Studio Team System

The training kit is a good way to get to know some of the new features of .NET 4 and Visual Studio 2010.

Using my example, I just added a table X to my database.  I then went to my Entity Framework model and did a “Update Module From Database” and selected my new table to add it to the model.  At this point the most important thing to do before worrying about .NET RIA Services is to save and build your project.  If you fail to do this its likely that when the .NET RIA Services wizard runs it won’t see the change yet.

Next, assuming we already have a Domain Service created let’s call it “MyDomainService" for our example.  You can’t simply right click and say “Update Domain Service and have it see the new Table X we just added.  So the simplest way right now to handle that is to create a new temporary domain service – let’s call it “MyDomainServiceTemp”.  When you see the selection of entities select only the new Table X you just added.  If you are allowing edit make that selection as well as indicate if you want metadata.  The wizard will now generate the files for the new temporary domain service.  Once the code generation is completed, open up the new domain service and copy the methods from the temp file to your real MyDomainServicve file.  You will need to do the same thing for the Metadata file that was generated.  Once you have copied the code from both files, delete the temporary domain service files from your project and build.  At this point you now have added the new Table X to your domain service.

Adding columns is easier, really the only thing you have to deal with if you add a column is to add it to the metadata buddy class.

I’ve already passed along my 2 cents that this should be a right click update model type experience, however, you too should post on the forums that you want it added as well!

When your debugging this can cause your debugger to break on the property setter each time a validation error occurs. 

After 5 or 6 times of getting that exception and having to switch over and continue will drive you crazy.  Yes, Microsoft is aware that throwing an exception for validation isn’t the best plan, but currently that’s the only option for Silverlight. 

You can turn off breaking on this unhandled exception by adding the type to the list of exceptions and unchecking breaking on user-unhandled exceptions of that type. 

Go to the Debug – > Exceptions menu item and click the Add… button on the right side  In the Type select “Common Language Runtime Exceptions” and input System.ComponentModel.DataAnnotations.ValidationException in the Name field.

After you click OK – you should now see it show up in the list as you do below.

Uncheck the far right check box “User-Unhandled” and it should look like the following

Now simply click “OK” to save the change and go back to your debugging without the interruptions!

You can start reading now about some of the changes since the beta here and here.

There’s also a good blog post here on the end to end security changes.  One highlight I saw was the right click enable of Bitlocker on a disk volume.

Another good one is on mobile security here – it talks about how in Windows 7 you will be able to have multiple active firewall policies.  The DirectAccess sounds real interesting I will have to add that to my list of things to research.  DirectAccess basically sounds like it deals with the need to jump on / off VPN to get to server resources like a SharePoint stored file.  BitLocker To Go (sounds like take out food!) is for removable USB drives – I’m hoping this will make it easier to protect the contents without driving me crazy!

Windows 7 will be able to Burn ISO Images Natively which will be nice (details here).  I didn’t see though what everyone wants ability to simply mount an ISO – let’s just hope I missed it and it will be a surprise!

I’m really looking forward to the RC, I’ve been running Windows 7 Beta since it came out on a desktop machine and my X61 tablet.  In reality the desktop was a better experience, but with the tablet the main issue was with the suspend and issues after it wakes up.  So like all things if you just don’t sleep you won’t have problems!  I chalk that all up to the drivers and hopefully now as we hit RC with this drop of Windows 7 things should be smooth on both computers.

So go put a note on your calendars to check MSDN on the 30th!

The application uses ADO.NET Data Services to do some queries for lookup values and other application data.  After a few tweaks for minor things to get it to run on Silverlight 3 I was off and running trying to get it to work out of the browser (OOB).  After doing the typical stuff  like looking for any HtmlPage.* calls and making sure they only happen if HtmlPage.IsEnabled is true I was able to get the application up and running.  In case your not familar with HtmlPage.IsEnabled it allows you to check if the Html Bridge is active and you can work with the HtmlPage elements.  When an application runs OOB you can’t make calls to HtmlPage.* methods without getting a Html/Dom is disabled unhandled exception being thrown.  So by wrapping any calls to HtmlPage with checks to see if the Html Bridge is enabled you can avoid that error when running OOB.

Ok, now back to the ADO.NET Data Services error – all was going well the application was starting up OOB.  Just when I thought things were going well I got a weird error on a Data Services calling “CreateNativeRequest”

Looking at the stack trace of the error showed this:

at System.Data.Services.Http.ScriptXmlHttpRequest.CreateNativeRequest()   at System.Data.Services.Http.ScriptXmlHttpRequest..ctor()   at System.Data.Services.Http.HttpWebRequest.InvokeRequest()   at System.Data.Services.Http.HttpWebRequest.BeginGetResponse(AsyncCallback callback, Object state)   at System.Data.Services.Client.QueryAsyncResult.BeginExecute()   at System.Data.Services.Client.DataServiceRequest.BeginExecute(Object source, DataServiceContext context, AsyncCallback callback, Object state)   at System.Data.Services.Client.DataServiceQuery`1.BeginExecute

I thought maybe it was because I was using a absolute Uri to talk to the host so I gave a relative URL a try in a test application  and got the following error:

at System.Windows.Browser.HtmlPage.VerifyThreadAndEnabled()   at System.Windows.Browser.HtmlPage.get_Document()
  at System.Data.Services.Client.DataServiceContext..ctor(Uri serviceRoot)
   at TestSL3DSOOB.PersonDS.MyContext..ctor(Uri serviceRoot)
   at TestSL3DSOOB.MainPage..ctor()

So you probably noticed the call to HtmlPage.get_Document above and can probably infer from that that it must be doing some HtmlPage.* calls which as we discussed earlier aren’t compatible with running Silverlight 3 OOB.

So at least for the beta, I’m going to have to wait to see if this gets fixed when Silverlight 3 releases but for now hopefully knowing about the issue will save you a few hours of head bashing!  That said, if you haven’t tried building a Silverlight 3 OOB application give it a try – I run a twitter client OOB and the funny thing is I still once and a while start looking for the browser address bar to type in a URL!

Speaking of Twitter – if your on Twitter add me to your list – http://Twitter.com/DavidYack

The most common scenario I’ve seen is where you have a user control in a class library “Lib A” and it’s used by an application “App A”.  When running App A it produces a AG_E_PARSER_BAD_Type when the user control in App A tries to call InitializeComponent().  What’s interesting is in trying to create a repro for the Silveright team I’ve tried several times creating an App B, and App C that use Lib A and no luck those work fine. 

What’s even more interesting is what I’ve found fixes it and gets the InitializeComponent() method to run fine.  Simply by creating an instance in the code behind of the Lib B user control prior to calling InitializeComponent does the job.  I could probably dig a little deeper to find why that helps, but sometimes a little mystery is ok!

So as you can see in the following example adding the dummy instance of MapBuilderControl did the job.

public PropertyMapping()

        {

  MapBuilderControl x = new MapBuilderControl();

            InitializeComponent();

        }

Clearly, that’s far from the ideal resolution, but if you find yourself getting this error – give it a try!

Silverlight however brings to the table a number of unifying concepts that both web and desktop developers should find appealing. Early on, Silverlight was thought by many to be simply a glorified Adobe Flash competitor offering a way to build a video player with the Microsoft tools. The reality, while it may well be a competitor in that space, its potential for being able to build rich business applications is really where it starts to get interesting. Additionally, as you consider the number of .NET capable developers already trained to build applications using similar Microsoft .NET related technologies it becomes clearer how Silverlight traction will begin to outpace competitors in the space at an amazing rate.

The time has arrived for anyone involved in business application architecture and related technology decisions to begin to engage in understanding the changing landscape. This would include not only ISVs, but also corporate developers building internal line of business applications. That's not saying everyone should move today to Silverlight, but should invest in understanding what changes are emerging. By making the investment in learning, you will be well positioned as the application user interface space continues to evolve over the next couple of years.

Today's introduction of Silverlight 3 beta makes real the commitment toward Silverlight being more than just a media player. Silverlight 3 introduces more business focused controls, more data and business logic connectivity as well as what could turn out to be the real “Click Once" deployment experience.

Silverlight 3 along with Microsoft .NET RIA Services extend the core connectivity plumbing to offer a richer way of extending business data and logic to the client application. As we will discuss in the future these services make it possible to share business logic as appropriate with the Silverlight client while keeping centralized business rules. This goes directly toward addressing and reducing complexity and developer productivity issues of these types of applications.

Traditionally, plug-ins like flash and Silverlight run in a web browser. As the lines between a true desktop application and a web application blur, so does the ability of Silverlight to run outside the browser. Live Mesh offered the first glimpse when it was announced at Microsoft PDC in October 2008 of a Silverlight application out of the browser with Mesh. Silverlight 3 continues that capability allowing a user to choose to install a Silverlight application to their start menu or desktop for easy access. When launched after saving the Silverlight application runs in a standalone process outside the browser window. Unlike competing technologies, this out of browser experience still allows the developer to use the same code and binaries both in and out of the browser. Using local storage resources and Silverlight's support to detect network availability these out of browser applications can also still run offline disconnected from the network. For many, this will be the unifying capability to further bring together desktop and web application development.

It's easy to jump to conclusions that ASP.NET is dead, or WPF is dead and it's important to understand how Silverlight fits in. The reality is, that all three technologies offer unique value propositions for developers building applications. While nobody has a crystal ball to predict the future we can look at how that plays out today. Today, ASP.NET offers applications the broadest deployment across a diverse set of clients. For broad consumer focused applications ASP.NET will continue to be the most viable option. Silverlight will start to be introduced more often in these applications as rich islands offering users specialized functionality. Developers will continue to build WPF applications to take advantage of having full access to desktop devices and the ability to have other desktop specific features. In some cases we will see lite versions of applications built on Silverlight, with full or more desktop feature enabled versions offered in WPF. In fact, frameworks and strategies are starting to emerge to improve the ability to build an application targeted for both Silverlight and WPF.

Join us as we continue to discuss and connect all these concepts into a clearer picture of how you build business applications using Silverlight. We will start with the basics of when to use Silverlight, move on to architecture concepts, and then steadily discuss the core building blocks that are required to put together a business application.

Earlier, we launched a new blog, a new Twitter account and soon a new website that will be supporting a Silverlight 3 book focused on building business applications with Silverlight. Soon we will be releasing more details about the book and how you can get early access.  If you would like to get notified sign up for the book notification list here.