My Silverlight app doesnt show changes - silverlight

Question

It's my first time with SL (but not WPF). Im learning PRISM watching the great videos of MTaulty: http://channel9.msdn.com/blogs/mtaulty/prism--silverlight-part-1-taking-sketched-code-towards-unity
So far so good, I'm with the last video and I'm doing the same things He does in my VS. I'm using SL4 & mvc2 web & prism for sl4.
I Found a problem and I don't know what is going on.
My SL application itself doesnt show any changes. I have a basic shell:
<Grid x:Name="LayoutRoot" Background="Azure">
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="2*" />
</Grid.ColumnDefinitions>
<ctls:GridSplitter Grid.RowSpan="2" HorizontalAlignment="Right"
VerticalAlignment="Stretch" Width="2"
Background="Black" />
<ctls:GridSplitter Grid.Column="1"
HorizontalAlignment="Stretch" VerticalAlignment="Bottom"
Height="2" Background="Black" />
<Border Background="SkyBlue" CornerRadius="3"
Margin="5" Grid.RowSpan="2">
<ContentControl rgn:RegionManager.RegionName="FolderSelectionRegion"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" />
</Border>
<Border
Background="SkyBlue"
CornerRadius="3"
Margin="5"
Grid.Column="1">
<ContentControl
rgn:RegionManager.RegionName="MailSelectionRegion"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
HorizontalContentAlignment="Stretch"
VerticalContentAlignment="Stretch" />
</Border>
</Grid>
The thing is, I registered a View in the first regionManager, perfect, I registered a second view but it doesnt show... Ok, some bug in someplace... but no.
I realized that the border for the second regionManager is not showing up, ok. I commented the line that register the view (the view is working) and the view is still showing up. I commented the bootstrapper, deleting it from Application_Startup, nothing the view is still showing up (not possible, there is no way that my app knows how to execute the Shell, is all commented out).
In short, I'm sure if I Delete 3 files, the app is still working... I cleaned the solution, deleted the .xap files from the ClientBin... Nothing, the app is still showing up the view and so on. On other words, the app is not reflecting changes on the code.
What's going on?
Thank you.
EDIT: Near one year later...
So, I didn't touch Silverlight since this, but today I wanted to make a very simple app (just a path and textbox) and... Yay my app started to dont show the changes.
I can't reproduce the bug, I don't know what trigger this, but I know that is a problem with ASP.NET MVC.
The project Im talking here, and the project I made today, both were using ASP.NET MVC to launch the SL project.
I uploaded the EmailClient project (just the part we are interested in) to my host: www.foxandxss.net/stuff/EmailClient.rar
Is easy to see the problem. For start, you can see that in Shell.xaml, the LayoutRoot's color is Azure and if you run the application, it will be Green (When I opened today this app, I changed it to Green and worked, but no more changes). If you change the color to another one, it didn't change. If you go to App.xaml.cs and comment the lines that creates and run the bootstrapper (so the app will not run), the app will still opening. Is like the app running is some cache and everychange you make, you wont see it.
I tried deleting the xap from the MVC project, and nothing.
The thing is that if you right click on the SL project and click on "View in browser" you will see the changes (Azure BG or nothing if you commented the boostrapper) but if you run it from the MVC project, nothing.

Answer 1

In the past, I had issues with XAP file caching. If it's the issue, I would inject a dummy parameter next to the xap file path (in this case a timestamp) :
<div id="silverlightControlHost">
<object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
<param name="source" value="ClientBin/EmailClient.xap?20110712160700"/>
<param name="onError" value="onSilverlightError" />
<param name="background" value="white" />
<param name="minRuntimeVersion" value="4.0.50826.0" />
<param name="autoUpgrade" value="true" />
<a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.50826.0" style="text-decoration:none">
<img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/>
</a>
</object><iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe></div>
If you refresh that parameter on each build, this should invalidate the cache and load the latest xap file.

Answer 2

Samuel has the right idea, however you can get Silverlight to automatically ignore previous timestamps by checking the last write time on the server
<div id="silverlightControlHost">
<object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
<%
const string orgSourceValue = #"ClientBin/SilverlightApp.xap";
string param;
if (System.Diagnostics.Debugger.IsAttached)
param = "<param name=\"source\" value=\"" + orgSourceValue + "\" />";
else
{
string xappath = HttpContext.Current.Server.MapPath(#"") + #"\" + orgSourceValue;
DateTime xapCreationDate = System.IO.File.GetLastWriteTime(xappath);
param = "<param name=\"source\" value=\"" + orgSourceValue + "?ignore=" + xapCreationDate.ToString("yyyy-MM-dd_HH-mm-ss") + "\" />";
}
Response.Write(param);
%>
<param name="onError" value="onSilverlightError" />
<param name="background" value="white" />
<param name="minRuntimeVersion" value="4.0.50401.0" />
<param name="autoUpgrade" value="true" />
<a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.50401.0" style="text-decoration:none">
<img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/>
</a>
</object><iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe></div>