Ian Blackburn

Bill Gates - school for the gifted

Ian Blackburn — Fri, 27 Jun 2008 21:14:55 GMT

Ian

Silverlight Transparency - use PluginBackground not Background!

Ian Blackburn — Fri, 27 Jun 2008 07:05:07 GMT

If you want to have your Silverlight control to have a transparent background, then it is simply a question of setting the properties that Mike Snows describes in his tip post.

What had caught me out previously and the reason for this post is that I had used the Background property of the Silverlight control, rather then the correct PluginBackground property. Confusingly this works for the Html control but not the Aspx one. I had in fact filed it as a bug, and perhaps it is because I am not sure we need both of those properties?

Cheers

Ian

Technorati Tags: Silverlight

Apple's Mobile Me == Windows Me (well the logo at least)

Ian Blackburn — Mon, 09 Jun 2008 19:01:31 GMT

Apple just announce MobileMe for push email, contacts and calendars for data in the cloud. Interesting stuff - but the logo? Hmmm.....

Cheers

Ian

Technorati Tags: MobileMe,Windows Me

Bridging Web Service Calls in Silverlight

Ian Blackburn — Fri, 06 Jun 2008 11:57:41 GMT

For security reasons, the Silverlight version 2 runtime restricts access to certain classes of URLs from the WebClient and HTTP classes in the System.Net namespace.

The main requirement is that the services you want to use should implement either crossdomain.xml (which is the Flash policy file) or clientaccesspolicy.xml (which is the Silverlight one). If the service you want to use does not implement one of these then you can't use Silverlight to access it.

However such restrictions are not present when using WebClient on the server, so you can easily create a bridge service that your Silverlight client can use.

For example you could create a very simple WCF Service in the same web site that will host your Silverlight app as follows:

using System;
using System.ServiceModel;

[ServiceContract]
public interface IFeeds
{
    [OperationContract]
    string GetFeed(Uri uri);
}

using System;
using System.Net;

public class Feeds : IFeeds
{
 

    #region IFeeds Members

    public string GetFeed(Uri uri)
    {
        WebClient client = new WebClient();
        return client.DownloadString(uri);
    }

    #endregion
}

Note: You need to change the Wcf service binding in web.config so that you use a basicHttpBinding rather than the wsHttpBinding (which is not supported by Silverlight)

<system.serviceModel>
 <behaviors>
  <serviceBehaviors>
   <behavior name="FeedsBehavior">
    <serviceMetadata httpGetEnabled="true" />
    <serviceDebug includeExceptionDetailInFaults="false" />
   </behavior>
  </serviceBehaviors>
 </behaviors>
 <services>
  <service behaviorConfiguration="FeedsBehavior" name="Feeds">
   <endpoint address="" binding="basicHttpBinding" contract="IFeeds">
    <identity>
     <dns value="localhost" />
    </identity>
   </endpoint>
   <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
  </service>
 </services>
</system.serviceModel>

Now you can add a service reference from your Silverlight application to this Wcf service and use it something like as follows:

private void Button_Click(object sender, RoutedEventArgs e)
  {
      ServiceReference1.FeedsClient client = new ServiceReference1.FeedsClient();
      client.GetFeedCompleted += client_GetFeedCompleted;
      client.GetFeedAsync(new Uri("http://timesonline.typepad.com/sports_commentary/atom.xml"));
  }

  void client_GetFeedCompleted(object sender, ServiceReference1.GetFeedCompletedEventArgs e)
  {
      TextBlock1.Text = e.Result;
  }

Cheers

Ian

Technorati Tags: Silverlight,Wcf,Crossdomain

Simple FriendFeed C# User Control

Ian Blackburn — Fri, 06 Jun 2008 10:00:15 GMT

We use a simple Friend Feed user control on our home page. We have found this a great way to share "filtered" information that is relevant to our customers.

What we have done is created a FriendFeed account called bbits, which we share things into (via google reader and other feeds).

The user control then picks the friendfeed up and displays this in a gridview.

When we did this FriendFeed didn't have any widgets, which they do have now, (and here) so if you prefer to use those rather than a c# user control go visit those pages now.

Our c# user control can be found below or from here (this also includes a modified version of the c# library produced by friendfeed, that solves a few small issues and bugs)

Cheers

Ian Blackburn

Technorati Tags: FriendFeed,User Control,c#

WCF: "a non-empty contract name must be specified"

Ian Blackburn — Tue, 03 Jun 2008 19:53:00 GMT

This error had me baffled today, and I could find little reference to it from Google or Live Search.

It was the result of creating a simple WCF Service with two methods as follows and then trying to add a reference to it from Silverlight 2:

[ServiceContract]
public interface IWcfService
{
    [OperationContract]
    string HelloWorld(string name);
    [OperationContract]
    List<Person> GetPeople();
}

public class WcfService : IWcfService
{
    public string HelloWorld(string name)
    {
        return "Hello World " + name;
    }


    #region IWcfService Members


    public List<Person> GetPeople()
    {
        List<Person> people = new List<Person>();
        people.Add(new Person() { FirstName = "Fred", LastName = "Bloggs", Age = 23 });
        people.Add(new Person() { FirstName = "Fred", LastName = "Smith", Age = 24 });
        people.Add(new Person() { FirstName = "John", LastName = "Bloggs", Age = 29 });
        return people;
    }

    #endregion
}

The service config looked good (having changed to a basicHttpBinding - which is the what Silverlight 2 supports:

<system.serviceModel>
  <behaviors>
   <serviceBehaviors>
    <behavior name="WcfServiceBehavior">
     <serviceMetadata httpGetEnabled="true" />
     <serviceDebug includeExceptionDetailInFaults="true" />
    </behavior>
    
   </serviceBehaviors>
  </behaviors>
  <services>
   <service behaviorConfiguration="WcfServiceBehavior" name="WcfService">
    <endpoint address="" binding="basicHttpBinding" bindingConfiguration=""
     contract="IWcfService">
     <identity>
      <dns value="localhost" />
     </identity>
    </endpoint>
   </service>
   
  </services>
 </system.serviceModel>

But I kept getting this error. And the other 6 delegates on the course I was delivering were getting exactly the same problem! I kept thinking that this was something to do with Silverlight, but I was barking up the wrong tree. It wasn't until I got on the train home, that it suddenly hit me, I had not marked the Person class with the DataContract and DataMember attributes! This was what was needed to sort it out:

[DataContract]
public class Person
{
    [DataMember]
    public string FirstName { get; set; }
    [DataMember]
    public string LastName { get; set; }
    [DataMember]
    public int Age { get; set; }
}

Still, in my defence, I think the cause of the error message wasn't that obvious.

Hope this helps someone!

Cheers

Ian

Technorati Tags: Silverlight,WCF

Windows Mobile - where is it heading?

Ian Blackburn — Thu, 29 May 2008 10:19:58 GMT

Todd helpfully re-published the Windows Mobile Silverlight roadmap recently. It does not make exciting reading. In amongst news of Impressive Google Android Apps, (and here) a T-Mobile Android phone this year (from HTC) and endless twitter about iPhone and 3G, the road map is hardly going to light any fires. Here's my take on the Windows Mobile roadmap in general, followed by my hope of a glimmer of light for all us WM developers and users...

Windows Mobile 6.1 was just released - really nothing to write home about - threaded SMS is nice but there is not much else here - in particular the Getting Started Application is very lame - just a list of items, that when clicked show some text and links to the real apps. The worst is the "Make a Call" option shown below - really does this add anything? Couldn't a few more images or even a little animation have helped? Why have the icon shown for step 1 but not step 3? My mum was just baffled by this, and my 12 year old daughter just could not understand why anyone would find this useful.

We are still waiting for Silverlight 1.0 support on Windows Mobile. At Mix08 I attended various mobile talks (Amit Chopra: "The wait is finally over, we have Silverlight for Windows Mobile" - from one of the less impressive sessions), where Silverlight 1.0 was promised shortly after Mix. According to Todd a CTP should be available soon - a CTP? of Silverlight 1? Come on guys, Silverlight 1 should be done and dusted by now, it was announced at Mix07, we need Silverlight 2 and a WPF-like UI.
Todd says: "We'll get the first "official" Silverlight for Mobile (1.0) towards the end of this year, sometime after Silverlight 2.0 officially ships for the desktop. Around the same time we should get a CTP of Silverlight 2.0 for Mobile." - That isn't very positive language, "should" sounds a little shaky to me. (Todd isn't employed by Microsoft though, so perhaps we shouldn't read too much into that)
Location Services - this is a high growth area - sales of Mobile Navigation devices has doubled and location based services are an important aspect of mobile development. Google look like they may make their Geolocation API public - this lets you get your location on devices that haven't got a built in GPS - using the Skyhook service, and is seen in Google Maps Mobile currently. Windows Mobile has the Intermediate GPS Driver and some sample code to get you started. However in our experience this sample is buggy and the Intermediate driver is implemented differently across different hardware manufacturers (ask me for details), making it hard for developers to take advantage of. Look how easy it is on Android - this is how it should be on Windows Mobile too.
UI - We all know there is plenty wrong with Windows Mobile UI - and that IPhone sales are beating WM in the US (though both are behind RIM and Symbian) and the Android will do the same IMHO. Microsoft will be acutely aware of this too, so why the delay for Silverlight on Windows Mobile?

The glimmer of light

OK so Windows Mobile is not in a great way compared to the competition at the moment, but is there any hope that Microsoft is actually keeping their rapid development of Windows Mobile 7 behind closed doors, and that they may actually get a device to the market this year, together with Silverlight and a UI that can compete with IPhone and Android? Well there may be. Some clues:

Microsoft bought Danger Inc - could this mean they are developing their own hardware for WM7 and beyond?
Rumour that MWg are launching a WM7 device this year
PDC Sessions 08: Windows Mobile: Location, Location, Location, Silverlight: Developing for Mobile Devices

I really hope Microsoft are planning to surprise us with Windows Mobile this year. Android is starting to get developers excited, and if they can get it out on more than the T-Mobile device, I think it offers real competition - we will certainly consider it for future mobile development, based on the look of the Api, but I would prefer to stay with Windows Mobile if it can improve it's api and UI support.

Cheers

Ian

Technorati Tags: Windows Mobile,Android,iPhone,Silverlight

Silverlight Course Materials (Helsinki 8/9 May)

Ian Blackburn — Thu, 22 May 2008 19:13:56 GMT

For those delegates who attended this course in Helsinki, and have not received copies of the sample applications we used, but would like them, please email me at Ian@bbits.co.uk and I will forward them on.

Cheers

Ian

Using ASP.NET Routing Independent of MVC - passing parameters to the page

Ian Blackburn — Mon, 19 May 2008 17:39:28 GMT

Mike Ormond has a nice post about how to use the Asp.Net routing capabilities of Asp.Net MVC, in your standard webforms sites.

In his example Mike goes through the essentials of how to set this up in Application_start and how to create and register your own IRouteHandler. Mike's example explains this really well with a simple example of routing a single parameter to a matching aspx page as follows:

URL	Mapped to:
http://mysite/home	http://mysite/RoutingDemoPages/default.aspx
http://mysite/default	http://mysite/RoutingDemoPages/default.aspx
http://mysite/page1	http://mysite/RoutingDemoPages/page1.aspx
http://mysite/page2	http://mysite/RoutingDemoPages/page2.aspx

I wanted to see how you can map multiple parameters to a single page and pass that parameter data to the page. So that the following mappings were made:

URL	Mapped to:
http://mysite/fred	http://mysite/default.aspx with info on Fred
http://mysite/fred/london	http://mysite/default.aspx with info on Fred in London
http://mysite/Mike/Glasgow	http://mysite/default.aspx with Mike in Glasgow

The first thing to do is to change the routes registered in global.asax, so that we have routes that expect our two parameters for username and area:

void Application_Start(object sender, EventArgs e) 
{
    RegisterRoutes(RouteTable.Routes);
}

private void RegisterRoutes(RouteCollection Routes)
{
    Route r = new Route("{username}/{area}" ,new SimpleRouteHandler());
    Route r2 = new Route("{username}", new SimpleRouteHandler());
    Routes.Add(r);
    Routes.Add(r2);
}

Next we need to modify the SimpleRouteHandler to deal with these routes. At first I expected an overload on the CreateInstanceFromVirtualPath method that let me pass some parameters, but that was not available. Instead I simple added the RouteData (which contains the username and area parameters) to the Context Items collection:

public IHttpHandler GetHttpHandler(RequestContext requestContext)
  {
      string virtualPath = string.Format("~/default.aspx");
      foreach (var value in requestContext.RouteData.Values)
      {
          requestContext.HttpContext.Items[value.Key] = value.Value;
      }
      return (Page)BuildManager.CreateInstanceFromVirtualPath(virtualPath, typeof(Page));

  }

Now I can work with those values on default.aspx (and in this case just display them):

protected void Page_Load(object sender, EventArgs e)
{
    Label1.Text = string.Format("username:{0} area:{1}", Context.Items["username"], Context.Items["area"]);
}

Cheers

Ian

Technorati Tags: MVC,Url Routing,Asp.Net

Virtual Earth 3d in the UK

Ian Blackburn — Sun, 11 May 2008 18:11:31 GMT

I have noticed that more and more places in the UK are getting the 3D treatment in Virtual Earth, but there doesn't seem to be a list of all of them (at least I couldn't find one). The UK models do not yet support the recent enhancements that some of the US cities have (such as Denver or Las Vegas) where vegetation is modelled as well as the buildings, but I expect that it is just a matter of time.

So anyway I have created a collection of places in the UK where I have spotted 3D models - bear in mind you need to switch to 3D view (doh) and that it takes a while for the models to fully load (keep your eye on the globe in the bottom left corner of the map - if it has not filled with colour then the map and models are not yet fully loaded in all their glory (my son : "that doesn't look very good dad it's just a load of colours - oh hang on, wow!"

The collection is here - I'll add to it as I spot any others, or if you see or know of any others, please let me know. Some examples below:

UPDATE: Found this collection of worldwide 3D cities: http://maps.live.com/?v=2&cid=320432CACC287CB4!101&encType=1#

Cardiff Millennium Stadium

Bristol Cathedral

Royal Pavilion in Brighton

Some tips for the 3D view

Enable "Continue Earth motion after dragging"

This is buried in the options > 3d settings dialog > preferences section, but really adds a nice effect when dragging the map - and if you zoom out to the entire globe, you can spin it round like a football!

Try the 3D tour

You can open any collection and tour it in 3D - just click the link above the collection:

Create your own 3D tours

You can control how your 3D tours are viewed by recording the best viewpoints, and adding info and images.

When you create a collection in 3D the properties for any pushpin has specific 3D options (shown below) such as capturing the current viewpoint, adding animations, waiting for the scene to load, and waiting before moving to the next pushpin.

In the collections editor you can then select Actions > Tour and make videos in 3D.

Turn your 3D tour into a video

It's really easy to turn a 3D tour into a video: In 3D tour window, just click the Record button, select some display options and click continue. It can take quite a while though, so you'll probably want to kick it off and go and make a cup of tea! Note that it does not seem to be too processor intensive for your machine, perhaps most of the work is being done on the server, so you could do some work rather than have a cup of tea, if you are that way inclined.

NOTE: The quality of the video can be set right up to HD quality, You need to do this before you click the record button in the options screen for VE (Click the options icon top right of the screen ). However my laptop (Lenovo T61p with 4GB Ram and Vista x64) fell over with an out of memory error when I tried to create a video at the highest 1920x1080 setting.

Host the video with Silverlight Streaming

if you create a video it is really very easy to host it for free at http://silverlight.live.com and embed it on any page you want (using Microsoft's bandwidth and infrastructure). This is free at the moment, and will remain so when the service goes live, provided you are happy for ads to appear on your videos. If you don't want ads then there will be a paid for service, or you can host the video yourself. Here's one I created earlier of a tour of the River Thames:

Technorati Tags: Virtual Earth,video,silverlight streaming