Another limitation of testing Silverlight that me and one of my workmates ran into with mstest and VS2010 is documented below.
OOP especially Polymorphism help us here though.
We try to test a method that takes an ObservableCollection as input parameter.
I would like to leave the discussion about whether a method with a parameter of type "ObservableCollection" is a good idea or not to another day…
This is the method we want to write some tests around
Many articles on the web, books and statistics tell us that “faster = better” and even more important: faster = more revenue.
For Google an increase in page load time from 0.4 second to 0.9 seconds decreased traffic and ad revenues by 20%.
For Amazon every 100 ms increase in load times decreased sales with 1%.
Also Google uses site speed in their web search ranking. So make sure to optimize your website for speed as per my other blog post.
Is Web Performance Optimization (WPO) something for you?
Thanks everyone for 2 great user group nights.
Here are my slides and my most important slide, based on Paul Stovell's blog post
Disclaimer
Before you start flaming me, I am aware that all business relevant code and IP stuff must be on the server side. Just funny how much bit**** you see in forums and stackoverflow if you search for "Silverlight obfuscation"
With tools like Reflector, ILSpy (which is a good Reflector replacement BTW, since Reflector is not free anymore) and Silverlight Spy, it is VERY easy to look into Silverlight XAP files and discover some interesting stuff. We cannot completely hide our source code, but we can at least make it harder to disassemble and see.
If you are a serious Silverlight developer, make sure to get a copy of Silverlight Spy. No, I am not related to them, working for them nor affiliated.
Do you know how to prevent users from losing changes in your Silverlight application, if they click the "back button" or "close browser" button?
We are using the WrapPanel from the Silverlight toolkit
Because we don't need the whole toolkit assembly, we copy/paste the source of the WrapPanel and use that.
Instead of the whole full blown assembly
Should be fine with the license: Ms-PL
Figure: Size of Silverlight toolkit assemblies
Imagine the following
So what do you do?
Instead of having endless support calls, email conversations, tracing in log files, lookups in log-databases etc… use the below Feedback Control
My question to you (developers & designers) about the context menu in Silverlight:
Is an application more user friendly, if there are no functions hidden in the context menu?
What do you think?
Note
To get a context menu before Silverlight 4 you had to set the Silverlight app to windowless and do some weird hacks (UGLY and performance issues!).
With Silverlight 4 we have a context menu out of the box (MSDN Silverlight Whitepaper).
NB (Nota bene, the italian note)
There is no out-of-the-box context menu on the iPad.
I really like the UX of the iPad, but there are some inconsistencies left. Read more here from these usability experts (german article)
Google Wave is pretty cool, and was a big hype in the beginning.
I still use for sharing some notes with others…
Building something similar like Google Wave in Silverlight should be fairly easy
Figure: RichTextBox control in action from MSDN
Google Wave = Big Silverlight Richtextbox that gets updates from others
How can we build it with Silverlight?
AND
How do other applications work, like EtherPad?
Everyone was VERY excited about the possibility to show HTML content inside Silverlight.
But soon we Silverlight developers realized that it wont work in a inside-browser scenario (if you can call it like that).
It’s a NOOB scenario where we need the browser control, just like the browsercontrol in Winforms (aahhh… the good old days, everything was better ;-)
NOOB = Not Out of Browser scenario
How can I reduce the size of my Silverlight application? And make it a better user experience on start-up?
Reminder to myself
All this is part of the Html bridge API of Silverlight, that allows talking to the browser
http://msdn.microsoft.com/en-us/library/cc645076(VS.95).aspx
To myself: Remember the following
Silverlight is “normally” hosted in the browser.
So, the single UI Thread should belong to the browser.
You can either learn that from different blogs, presentations or you learn it the hard way, like myself.
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If you get this nice error message, you are probably lost, because there is no hints on WHY!!!???
Microsoft Visual Studio
---------------------------
Unable to start debugging. The Silverlight Developer Runtime is not installed. Please install a matching version.
When you create a Silverlight project, VS looks for the HKLM,SOFTWARE\Microsoft\Silverlight\Components\Debugging reg key to make sure you have the dev runtime.
And when you debug, Silverlight looks for the HKLM\Software\Microsoft\.NETFramework\DbgpackShimPath reg key.
Thanks Amy!! Check out her blog about Silverlight and web dev
So your registry should have those keys and pointing to
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Silverlight\Components\Debugging
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\.NETFramework
Both these keys should point to the same version (see my examples for Silverlight RTM)
If you get the following problem in Expression Blend 3.0.1927.0: “Unsupported project”
Figure: Error messages in Expression Blend
Add the following pieces manually to your project file (.proj)
<PropertyGroup Condition="'$(MSBuildToolsVersion)' == '3.5'">
<TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
</PropertyGroup>
and (not sure if that is actually needed…)
<ExpressionBlendVersion>3.0.1927.0</ExpressionBlendVersion>
Figure: Applied changes to the .proj file
Reason: Expression Blend is not .NET 4 aware, so it needs this switch at the top of the project file
How would you implement an online chat application?
Which technology would you use?
--------
We are building something similar and have the following requirements
We tested and verified different technology options like:
The signs for HTML 5 web sockets are not so good, even though the promise for the socket implementation sounds interesting!
But it seems that HTML 5 is not going to be ready before ~201X, X > 2 and not sure what that X is…
More here
http://blogs.techrepublic.com.com/programming-and-development/?p=718
http://www.webmonkey.com/blog/HTML_5_Won_t_Be_Ready_Until_2022DOT_Yes__2022DOT
We finally are using "Silverlight with Duplex WCF over TCP”
And falling back to "Silverlight with Duplex WCF over HTTP” when we have a firewall or proxy in the middle that causes connection problems.
The main reason for going in that direction was:
PS
There is a new HTTP polling duplex mode added in Silverlight 4 RC, called “MultipleMessagesPerPoll”, makes this technology even more interesting
(Scroll to the bottom for the nice UI)
Figure: Karaoke machine UI done by a Developer :-)
See how easy that is, with Silverlight!!!
![clip_image002[4]](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZhQyZ6YVw8ctDywsxo6MPxcESAboK2xvdy9AWW_yebNu8wvf8kAlBF-144Wu1HQN-blabJ7No8om-HlmnaaPoVR87HPpG-Ej2odfBaQGyhZhIxzhPtZNb0v41vOZ7ZosTgOvLrQ/s1600-h/clip_image002411.jpg "clip_image002[4]")
Figure: Silverlight application calls the local web server, which calls the Lyrics web server
It’s that complicated, because cross domain access is blocked in Silverlight and the Lyrics web service doesn’t have a clientaccesspolicy.xml file
“Silverlight SDK Toolkit”
Download “Silverlight SDK Toolkit” from MSDN
Figure: Create a Silverlight project
[WebMethod]
public org.lyricwiki.LyricsResult GetSong(string artist, string title)
{
org.lyricwiki.LyricWiki lyricWiki = new org.lyricwiki.LyricWiki();
return lyricWiki.getSong(artist, title);
}
Build your solution!
Create the layout (page.xaml)
<UserControl x:Class="SilverlightApplication.Page"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Width="400" Height="300">
<StackPanel>
<TextBlock Text="Artist"></TextBlock>
<TextBox x:Name="textBoxArtist" Width="200" Margin="5" Height="50"></TextBox>
<TextBlock x:Name="Artist" Text="Title"></TextBlock>
<TextBox x:Name="textBoxTitle" Width="200" Margin="5" Height="50"></TextBox>
<Button x:Name="buttonStart" Content="Start fun!" Margin="10" Width="100" Height="50" Click="buttonStart_Click"></Button>
<TextBlock x:Name="textBlockResult" FontSize="20" Text="nothing so far" Margin="10" Height="30" Width="700"></TextBlock>
</StackPanel>
</UserControl>
Figure: XAML for the ugly Karaoke player
Code! Finally :-)
Use a timer to tick every 100 milliseconds and scroll through the lyrics
DispatcherTimer timer = new DispatcherTimer(); timer.Interval = new TimeSpan(0, 0, 0, 0, 100); timer.Tick += new EventHandler(timer_Tick);
On each timer tick, we scroll the text
private void ScrollText()
{
// Scroll 1 caret to the left, I know thats not nice :-) but easy!
textBlockResult.Text = textBlockResult.Text.Substring(1) + textBlockResult.Text.Substring(0, 1);
}
Create the event handler on song completed call
//No code, tooo easy
Create the timer and start it after song completed call
//No code, tooo easy
Remember: Everything is async in Silverlight
1. Add a slider for the speed of the text
Figure: Slider for adjusting the speed of the text scrolling
2. Make your Silverlight application look pretty
3. Make the text show only 1 line full, the other lines with low opacity
Google for: Silverlight Opacity
4. Scroll the text line by line (instead by characters)
Search for the first Newline in the text and split the text there
5. Make the application go in full screen after start
Have a look at http://www.silverlightshow.net/tips/Tip-How-to-enter-full-screen-mode.aspx
6. If no title entered, let the user choose from a list of songs by the artist
7. Make the song scroll like Star wars
See http://franksworld.com/blog/archive/2009/05/01/11451.aspx
8. Embed a youtube video next to the text of that song
See http://code.google.com/apis/youtube/overview.html for details on calling the youtube webservice
