April 2008 - Mike Taulty's Blog

I spent about 2 hours trying to figure this out today so I thought I'd just share it here. Mostly, the time lost comes down to Javascript but that's no big surprise :-( Essentially, I'm playing with the HTML Bridge that lets Silverlight .NET code call Javascript code and vice versa. It's all working very smoothly until I want to create an instance of a .NET type ( marked as ScriptableType ) from Javascript. I know that somewhere, there's a method that may be called; createObject createManagedObject createManagedInstance but I can't figure out what the heck it's called and I can't figure out a decent way of figuring that out :-) So...with Silverlight 2 Beta 1 I can confirm that if you have a .NET type such as; [ScriptableType] public class Point { [ScriptableMember] public int X { get; set; } [ScriptableMember] public int Y { get; set; } } and if you've registered this for use from Javascript at some point by calling something like this ( from .NET code ); HtmlPage.RegisterCreateableType( "PointType" , typeof ...

If you've been to our MSDN Roadshows ( approx 800 of you so far - thanks and thanks also for the feedback which we've gone through for Cardiff and London already ) or if you are planning to come along then you'll know that this year we're using cinemas. This has some serious upsides ( which is why we did it ); Huge screen. Tiered seating ( combined with (1) this means no-one has problems seeing what we're doing :-) ). Comfortable seating ( hey, you're sitting still for maybe 5-6 hours - previous venues have tended to use pretty uncomfortable chairs ). And some downsides; Loading people to/from the cinema takes time. Cinemas tend to have nowhere to sit in their foyers. and possibly some more. One of the things that you might have spotted happening in the cinemas this time around is the displaying of some interesting new logos that have been drawn up in the UK office. Things like this; Now, I have to admit that I was a little sceptical (who, me???!?) around these when I first saw them but I like their use on the...

Very interesting post over here .

Thanks to the people who came along to my talk on Entity Framework at VBUG in Bristol yesterday. I promised that I'd make the slides available and they can be found here for download in PPTX format and PDF format . This was more or less the same talk as I delivered at Southampton the week before so these resources are also relevant.

I passed across some code to Daniel just last night as he was struggling to get LINQ to XML to read some XML data from a web site ( actually, a web service ) for him. One of the things I miss in Silverlight ( from WPF ) is the ability to naturally bind to XML data and this discussion with Daniel prompted to wonder what I could do about writing classes that make XML data binding more declarative. Approach 1 ( not going to work ) My first instinct was to see if I could implement my own markup extension so that in markup I could write something like; <ListBox ItemsSource="{XmlBinding Source=foo.xml, Path=/foo/item}"/> and then maybe in the template for that ListBox I could use something like; <TextBlock Text="{XmlBinding Path=@value}"/> or something along those lines. However, there's a number of things that would stop me being able to do that; Silverlight doesn't support custom markup extensions like {XmlBinding} above so, naturally, that's really "game over" for this idea. There's also a couple of other...

I encountered a chap the other day who was building an application which did something like this; Play a video Load a set of times and thumbnail images from an XML file. Highlight the thumbnail images at the point where the video hits the right position. I thought this was a great example of how easy it can be to build solutions with Silverlight 2 ( regardless of whether Expression Encoder can already do some/all of this for you automatically ). Starting with a UI, I might have; < UserControl x:Class ="SilverlightApplication12.Page" xmlns ="http://schemas.microsoft.com/client/2007" xmlns:x ="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:controls ="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls" > < Grid x:Name ="LayoutRoot" Background ="White" > < Grid.RowDefinitions > < RowDefinition Height ="7*" /> < RowDefinition Height ="3*" /> </ Grid.RowDefinitions > < MediaElement x:Name ="media" Source ="{Binding VideoUri}" HorizontalAlignment ="Center...

Just something that I came across recently. If I have a ListBox like this; <Grid x:Name= "LayoutRoot" Background= "White" > <ListBox ItemsSource= "{Binding}" > <ListBox.ItemTemplate> <DataTemplate> <Button Content= "Click Me" Click= "OnClick" /> </DataTemplate> </ListBox.ItemTemplate> </ListBox> </Grid> and I write code behind it like this; public partial class Page : UserControl { public Page() { InitializeComponent(); this .Loaded += new RoutedEventHandler(Page_Loaded); } void Page_Loaded( object sender, RoutedEventArgs e) { this .DataContext = Enumerable.Range(1, 9); } void OnClick( object sender, EventArgs args) { } } Then I find it difficult to click on the buttons in the ListBox as below; That is - if I click on the button in the selected item (red squiggle) then that seems to work fine. If I click on the button within a non-selected item (yellow highlight) then it doesn't fire its Click event. It only works as a button when I select that item first ...

Just something that someone asked me about today so sharing here. Imagine that you want to define a portion of your Silverlight application but leave some other piece to run time. For example - a calculation engine or perhaps something more complicated like a piece of UI with interaction. You can dynamically load up a .NET assembly in Silverlight at runtime, pull out known types from it and interact with them just like you would in any other .NET application. I made my example as simple as possible. I defined a core UI which looks like this; The idea is that the red bit is the "host" and the yellow bit is for the plug-in editor. I define an interface to live between my host and my plug-in editor; public class TextEventArgs : EventArgs { public string TheText { get; set; } } public interface IEditUI { UIElement GetControls(); void SetText( string text); event EventHandler<TextEventArgs> TextChanged; } and then an implementation of that which I put into an assembly called Implementation which is not referenced...