The art of simplicity

The last few months, a discussion is going on about what’s the best technology for the future, Silverlight or HTML5. This discussion was further encouraged by the recent announcements about Windows 8 focussing on HTML 5 and Javascript. I don’t want to start the discussion again but if you have to make a decision today, this is a post that can help you compare both technologies: http://blogs.msdn.com/b/eternalcoding/archive/2011/06/13/html-5-vs-silverlight-5.aspx

Last week I did some test with the new Silverlight 5 functionality. Afterwards I reverted the solution back to Silverlight 4. But from that moment on, compilation started to fail with the following error messages: The strange thing was that all the necessary references were available. After trying a lot of things, I was able to solve the problem in the end by removing my userfile (*.suo) from the solution directory. Visual Studio recreated the file the next time I opened the solution and everything was working again.

On May 26th, Ordina Belgium(the company I work for) is organizing a free technology event. Ordina’s technology specialists will give 21 30 minutes sessions , spread over 5 tracks. The event is free for everyone to join, registration is required. You can register here: www.ordina.be/differentiate . We will have the following sessions for you to attend: Agenda: Stand out from the crowd with Microsoft technology on May 26, 6 pm 30-minute sessions – the choice is yours .Net Visual Studio LightSwitch Building a Windows Phone 7 application: lessons learned C#5 Async SharePoint Automated scripted deployment of SharePoint SharePoint 2010: architectural overview Developing against SharePoint 2010 lists SQL Where .Net meets SQL Server: SQL CLR Extending to multilingual reporting Using geo data within Report Builder 3.0 Application Lifecycle Management Automate your deployment cycle with TFS Build 2010 and Workflow...

When trying to deploy a WP7 app  inside Visual Studio to the device, it suddenly started to fail with the following error: “Error - This operation returned because the timeout period expired.” Same problem when using the deployment tool. Restarting my phone, restarting my pc,… nothing worked. So I started to think what was different then before. I realized that my Wi-Fi connection was enabled on the Phone. Could that be the problem? So I disabled Wi-Fi again, tried to deploy and indeed this time it worked!

While debugging my Windows Phone 7 app in the emulator, each time the application was tombstoned or closed, the following exception was raised: An error occurred while accessing IsolatedStorage. at System.IO.IsolatedStorage.IsolatedStorageSecurityState.EnsureState() at System.IO.IsolatedStorage.IsolatedStorageFile.get_AvailableFreeSpace() at System.IO.IsolatedStorage.IsolatedStorageSettings.Save() at System.IO.IsolatedStorage.IsolatedStorageSettings.TrySave() at System.IO.IsolatedStorage.IsolatedStorageSettings.SaveAllSettings() at MS.Internal.FrameworkCallbacks.ShutdownAllPeers() The error is clear, there is a problem with accessing the IsolatedStorage. But why? If I didn’t debug the application or when I deployed to a real phone, I never noticed the issue. So I hope it’s related to a bug in the emulator. .. Anyone out there who is having the same problem?

With the large amount of updates and new tools that Microsoft keeps throwing at us, you sometimes miss one. One recent updated that I just noticed, was an update of the Visual Studio 2010 Training Kit. You can download the Training Kit by going here: http://www.microsoft.com/downloads/en/details.aspx?FamilyID=752CB725-969B-4732-A383-ED5740F02E93&displaylang=en Or if you want to view it online, you can go here: http://msdn.microsoft.com/en-us/VS2010TrainingCourse All content has been tested to work with Visual Studio 2010 SP1. The setup scripts for all hands-on labs and demo scripts have also been updated so that the content can easily be used on a machine running Windows 7 SP1. And finally a list of the new content: Silverlight 4 Hands-on Lab - Migrating a Windows Forms Application to Silverlight Hands-on Lab - Migrating an ASP.NET Web Forms Application to Silverlight Hands-on Lab - Working with Panels, XAML and Controls Hands-on Lab - Silverlight D...

Building WP7 apps is fun and challenging. Every tip that can help improving the application experience is welcome! Jeff Wilcox, the creator of the 4th & Major app , published a checklist with some great tips focussing on the Windows Phone user interface.

Everyone likes things for free.  So here is a free ebook “ Silverlight for Windows Phone ” written by Puja Pramudya from Microsoft Innovation Center, Indonesia. This e-book is written for those who want to get to know, use, and develop applications for Windows Phone, Microsoft’s latest mobile platform. The download link and more information here . I didn’t had time yet to read it myself, but it’s on my list…

While browsing around, I noticed a new code drop on the EntLib codeplex site containing the Enterprise Library 5.0 Silverlight Integration Pack . Most important features are: port of the Validation Application Block new pieces of the infrastructure to support XAML-based configuration async configuration loading Note there is also a conversion tool to facilitate the reuse of your Enterprise Library existing configurations and convert them to XAML. It can be plugged in the config tool via a wizard or you may integrate it in your build process. The conversion tool is still rough and we are iterating on it. Both a demo and  a short screencast are available to get you started.  

This week a customer wanted to access the Azure blob storage from their Silverlight and Flash client applications. However due to the cross-domain restrictions of both technologies, we couldn’t access the blob storage out-of-the-box. Let’s see how we can solve this and enable full access to blob storage through Silverlight and Flash. ClientAccessPolicy.xml When a Silverlight application makes a cross-domain call (other than those that are allowed by default ), it first fetches a file called ClientAccessPolicy.xml from the root of the target server. For the blob storage this will be something like http://{namespace}.blob.core.windows.net/ . Every blob in Windows Azure storage lives within a container, but there’s a special root container which lets us store blobs directly off the root of the domain. This is where we’ll put our ClientAccessPolicy.xml file. The following code creates a publicly readable root container and creates a blob named ClientAccessPolicy.xml within it: private v...

This Tuesday I gave a presentation about Caliburn.Micro for the Visual Studio user group in Belgium( www.visug.be ). I already uploaded the presentation , but now I also added the sample application I’ve used. Download it here . Some interesting parts of the application: The default IoC functionality inside the bootstrapper is replaced by MEF. Check the MefBootstrapper.cs file in the Core folder. Some interesting IResult implementations are also available: BusyResult: Shows/hides a loading indication. ShowScreenResult<T>: Activates a specific screen on the Conductor. QueryResult: Executes a query on the backend and returns the results. CommandResult: Executes a command on the backend. A lightweight CQRS(Command-Query separation) implementation. Check the Model folder. A simple Conductor<T> implementation Convention over configuration And of course all the reasons why Caliburn.Micro is such a great framework: No Code Behind No Event Wireups No Commands No Dat...

On Tuesday, February 08, 2011 I’m doing a session about Caliburn.Micro for the Visual Studio User group in Belgium. You've heard a lot about Model-View-ViewModel (MVVM), but you've struggled to see how it can help you in your day-to-day work. Or, you're experienced at implementing MVVM, but looking for some ways to maximize your investment in this methodology. In this session, we explore Caliburn.Micro( http://caliburnmicro.codeplex.com/ ), a simple MVVM framework, by iteratively identifying pain points in our UI development and eliminating them with simple solutions. You'll walk away with code, but more importantly with an understanding of how to apply some simple ideas to improve productivity with MVVM in your own projects. Be there!

Looking for some nice icons to use inside your Windows Phone 7 application? First have a look  at the Windows Phone 7 icon pack. This package contains a set of 64 app bar icons that you can use when developing applications for Windows Phone. In addition to the 64 icons in PNG format (32 dark and 32 light), this package also contains vector versions that can be easily imported into Microsoft Expression Blend. UPDATE: The Icon Pack is now part of Expressions Blend for Windows Phone. When you are working with the application bar and add items you can change the icon used using a drop down in Expressions Blend for Windows Phone. When you select an icon it is automatically added to your project. If you want to get to the icons to work with them yourself you can find them on your drive in C:\Program Files\Microsoft SDKs\Windows phone\v7.0\Icons. . Another option is this package created by  Bil Simber .  It contains 502 Metro style icons in PNG, XA...

For as long as I can remember, developers(but also all other kind of IT people) have religious descussions about ‘there’ technology; Java vs .NET, stored procedures vs dynamic SQL, client side vs server side and so on.. And just when you think people start agreeing the next discussion knocks on your front door. One interesting discussion I followed closely last year(it already seems so long ago) was ASP.NET WebForms vs MVC . I especially liked the post by Scott Guthrie showing some common sense on the debate. I totally agree with Scott’s point about the nature of technical debates, and the acceptance that some technologies suit better for some problems. However with the emergence of new web technologies like CSS 3 and HTML 5, the growth of REST and the renewed interest in Javascript, I want to re-open the discussion. I think that architecting ASP.NET MVC applications will have a lot more potential than WebForms. Just think for a second what you have to do to transform your curren...

The last few weeks, there was a lot of buzz around the future of Silverlight. Although there were some official comments , the rumors kept going. For the remaining skeptics,  what can be a better answer than the announcement of Silverlight 5. A t the Silverlight FireStarter event Microsoft announced the timeline for Silverlight 5 in 2011.  Silverlight 5 was the main subject of  Scott Guthrie’s keynote where Microsoft demoed many of the coming new features and capabilities.  Silverlight 5 will be in beta the first half of 2011 and ship early in the second half of 2011. Some of the impressive improvements(note especially XAML debugging): Silverlight 5 Media improvements: Hardware Decode & Presentation of H.264 performance improvements using GPU support Trickplay with fast-forward and rewind support w/normal audio pitch Improved power awareness Remote-control support Digital Rights Management advancements Application Development impro...

When referencing controls from another assembly in XAML, you probably use the xmlns:myAlias="clr-namespace:MyNamespace;assembly=MyAssembly" syntax. Last week I discovered you also have another option, you can use an Uri instead of a namespace reference thanks to the XmlnsDefinition attribute. (Read more about this attribute on MSDN ). It allows you to map a XAML namespace to one ore more assembly namespaces. So how do you use it? Open the AssemblyInfo.cs file under the Properties folder of your project. Add the following line for each namespace in your assembly you want to map: 1: [assembly: AssemblyTitle( "WPF Namespace Sample" )] 2: [assembly: AssemblyDescription( "" )] 3: [assembly: AssemblyConfiguration( "" )] 4: [assembly: AssemblyCompany( "" )] 5: [assembly: AssemblyProduct( "WPF Namespace Sample" )] 6: [assembly: AssemblyCopyright( "Copyright © 2010" )] 7: [assembly: AssemblyTra...

When I tried to open a Silverlight project inside Visual Studio 2010, it failed with the following error message: “The imported project "C:\Program Files\MSBuild\Microsoft\Expression\Blend\3.0\Silverlight\Microsoft.Expression.Blend.Silverlight.targets" was not found.” When I tried to open the project on another machine it worked fine. So I realized that it had to be an installation issue. After comparing the two systems I noticed that the Blend 4.0 SDK wasn’t installed on one machine. After installing the SDK everything worked perfect.

At DevConnections , Microsoft announced that Visual Studio 2010 Feature Pack 2 will be available in the next couple of weeks.  Feature Pack 2 will contain enhanced testing support for Silverlight and Firefox applications along with a UI editor for coded UI tests . Microsoft Visual Studio 2010 Feature Pack 2 enables the following scenarios: Silverlight 4 support: Capture and playback of Action Recordings for Silverlight 4 Applications. Automated coded UI tests to be written and executed against Silverlight 4 applications Ongoing edits to coded UI test projects using a graphical editor.   Firefox Support: Fast Forward of action recordings from Microsoft Test Manager for Mozilla Firefox 3.5+ Automated testing from Microsoft Visual Studio 2010 for Mozilla Firefox 3.5+ (playback only).   Feature Pack 2 is a cumulative feature pack where Visual Studio 2010 Feature Pack 1 (“Visual Studio 2010 Visualization and Modelin...

Of course we are all waiting for the new async features in C# 5 as announced by Anders Hejlsberg at PDC 2010.(Download the Visual Studio Async CTP ), implementing a set of changes to the C# language that support a new pattern for asynchronous programming. In the meanwhile we still have to do it the old fashion way by executing work on background threads and marshalling the results back to the main UI thread. One very important player in this story are the different implementations of the SynchronizationContext class. Depending on the kind of application, different implementations are used. Windows Forms: System.Windows.Forms.WindowsFormsSynchronizationContext , used by the GUI thread(s) in Windows Forms applications. Other threads in the same application may use different SynchronizationContext implementations. Windows Presentation Foundation and Silverlight: System.Windows.Threading.DispatcherSynchronizationContext , used by the GUI thread(s) in Windows Presentation Founda...

If you are building Silverlight projects on the ISOAPP502 build server, it’s possible that the build will fail with following error: C:\Program Files (x86)\MSBuild\Microsoft\Silverlight\v3.0\Microsoft.Silverlight.Common.targets (101): The Silverlight 3 SDK is not installed. C:\Program Files (x86)\MSBuild\Microsoft\Silverlight\v3.0\Microsoft.Silverlight.Common.targets (101): The Silverlight 3 SDK is not installed. C:\Program Files (x86)\MSBuild\Microsoft\Silverlight\v4.0\Microsoft.Silverlight.Common.targets (104): The Silverlight 4 SDK is not installed. C:\Program Files (x86)\MSBuild\Microsoft\Silverlight\v4.0\Microsoft.Silverlight.Common.targets (104): The Silverlight 4 SDK is not installed. At first you should think that the SDK wasn’t installed on the build server. But connecting to the build server confirmed that the SDK was available. The reason of the failure had to be found somewhere else. It is caused by the fact that the new build engine runs by default in...