Jarred Capellman

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Yesterday I presented two sessions at the Blue Ocean Competition on Xamarin, Azure and the C# ecosystem in general. From the reaction received after my sessions the students seemed to have really been captivated by the possibilities afforded them by using Xamarin Forms, Azure and C# to turn their ideas into real products.

As mentioned during my presentation, I created a full Xamarin Forms demo for Android, iOS and Windows Phone tied to Azure Mobile Services. The full source code I put up on my github account here. For those not use to Git, I also packaged together all of the code into a zipfile here.

I developed the demo in Visual Studio 2013 Update 4, but it should work in the 2015 preview as well.

Those looking for the Powerpoint presentation you can download it here.
After a failed attempt earlier this week (see my post from Tuesday night) to utilize the CLR that is bundled with Windows IoT, I started digging around for an alternative. Fortunately I was on Twitter later that night and Erik Medina had posted:



Not having any time Wednesday night to dive in, I spent a few hours Thursday night digging around for the Mono for Windows IoT. Fortunately, it was pretty easy to find Jeremiah Morrill's Mono on Windows IoT Blog post, download his binaries and get going.

For those wanting to use Xamarin Studio or MonoDevelop instead of Visual Studio after downloading the binary from Jeremiah, you'll need to add mcs.bat to your bin folder, with the following line (assuming you've extract the zip file to mono_iot in the root of your C drive):
[bash] @"C:\mono_iot\bin\mono.exe" %MONO_OPTIONS% "C:\mono_iot\lib\mono\4.5\mcs.exe" %* [/bash] For whatever reason this wasn't included and without it, you'll receive:
[bash] Could not obtain a C# compiler. C# compiler not found for Mono / .NET 4.5. [/bash] Inside of Xamarin Studio, goto Tools -> Options and then scroll down to Projects -> .NET Runtimes and click add to the root of the mono_iot folder. After you've added it, it should look like the following (ignoring the Mono 3.3.0 that I installed separately):

Xamar<span classin Studio with Mono for Windows IoT setup" />

In addition you'll need to copy the lib folder to your Galileo and at least mono.exe and mono-2.0.dll, both found in the bin folder from Jeremiah's zip file to the folder where you intend to copy your C# executable. You could alternatively after copying over the entire mono_iot folder structure add it to the path like so (assuming once again you've extracted to c:\mono_iot) over a Telnet session:
[bash] C:\mono_iot\bin>setx PATH "%PATH%;c:\mono_iot\bin" SUCCESS: Specified value was saved. [/bash] In order for the path variable to update, issue a shutdown /r.

If you want to see the existing variables and their values you can issue a set p which will list the following after you've rebooted your Galileo:
[bash] Path=C:\windows\system32;C:\windows;C:\wtt;;c:\mono_iot\bin PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC PROCESSOR_ARCHITECTURE=x86 PROCESSOR_LEVEL=5 PROCESSOR_REVISION=0900 ProgramData=C:\ProgramData ProgramFiles=C:\Program Files PROMPT=$P$G PUBLIC=C:\Users\Public [/bash] With the environment variable updated, you'll no longer have to either copy the mono executable to the folder of your app nor include the full path over Telnet - definitely a time saver in my opinion.

Now back to deploying my little WebClient test from Tuesday with Mono...

From Visual Studio you don't need set anything up differently, however I was running into issues with the app.config when compiling from Visual Studio and deploying a little test app to my Galileo:
[bash] System.AggregateException: One or more errors occurred ---> System.TypeInitializationException: An exception was thrown by the type initializer for System.Net.HttpWebRequest ---> System.Configuration.ConfigurationErrorsException: Error Initializing the configuration system. ---> System.Configuration.ConfigurationErrorsException: Unrecognized configuration section [/bash] So I went back to using Xamarin Studio, but received the following:
[bash] System.Net.WebException: An error occurred performing a WebClient request. ---> System.NotSupportedException: http://www.bing.com at System.Net.WebRequest.GetCreator (System.String prefix) [0x00000] in :0 at System.Net.WebRequest.Create (System.Uri requestUri) [0x00000] in :0 at System.Net.WebClient.GetWebRequest (System.Uri address) [0x00000] in :0 at System.Net.WebClient.SetupRequest (System.Uri uri) [0x00000] in :0 at System.Net.WebClient.OpenRead (System.Uri address) [0x00000] in :0 --- End of inner exception stack trace --- at System.Net.WebClient.OpenRead (System.Uri address) [0x00000] in :0 at System.Net.WebClient.OpenRead (System.String address) [0x00000] in :0 at (wrapper remoting-invoke-with-check) System.Net.WebClient:OpenRead (string) [/bash] Not a good sign - essentially saying WebClient isn't supported. Got me thinking to verify the version of Mono from Jeremiah:
[bash] C:\>mono -V Mono JIT compiler version 2.11 (Visual Studio built mono) Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com TLS: normal SIGSEGV: normal Notification: Thread + polling Architecture: x86 Disabled: none Misc: softdebug LLVM: supported, not enabled. GC: Included Boehm (with typed GC) [/bash] From the 2.x branch not the newer 3.x branch like what I utilize at work for my iOS and Android development, but not wanting to go down the path of creating my own 3.x port I kept diving in - attempting to try the HttpClient that I knew wasn't supported by Windows IoT's CLR. I threw together a quick sample to pull down the compare results from jcBENCH to the console:
public async Task < T > Get < T > (string url) {
     using (var client = new HttpClient()) {
     var result = await client.GetStringAsync(url); return JsonConvert.DeserializeObject < T > (result); }
}
public async void RunHttpTest() {
     var result = await Get < List < string > > ("http://www.jcbench.com/api/CompareResults"); foreach (var item in result) {
     Console.WriteLine (item); }
}
]]>
As far the project was concerned I added the .NET 4.5 version of Newtonsoft.Json.dll to the solution via NuGet and made sure it was copied over during deployment. With a bit of a surprise:
[bash] C:\winiottest>mono winiottest.exe AMD A10-4600M APU with Radeon(tm) HD Graphics AMD A10-7850K Radeon R7, 12 Compute Cores 4C 8G AMD A6-3500 APU with Radeon(tm) HD Graphics AMD A6-5200 APU with Radeon(TM) HD Graphics AMD Athlon(tm) 5150 APU with Radeon(tm) R3 AMD Athlon(tm) 5350 APU with Radeon(tm) R3 AMD C-60 APU with Radeon(tm) HD Graphics AMD E-350D APU with Radeon(tm) HD Graphics AMD E2-1800 APU with Radeon(tm) HD Graphics AMD FX(tm)-8350 Eight-Core Processor AMD Opteron(tm) Processor 6176 SE ARMv7 Processor rev 0 (v7l) ARMv7 Processor rev 1 (v7l) ARMv7 Processor rev 2 (v7l) ARMv7 Processor rev 3 (v7l) ARMv7 Processor rev 4 (v7l) ARMv7 Processor rev 9 (v7l) Cobalt Qube 2 Intel Core 2 Duo Intel Core i5-4300U Intel(R) Atom(TM) CPU Z3740 @ 1.33GHz Intel(R) Core(TM) i3-2367M CPU @ 1.40GHz Intel(R) Core(TM) i7-4650 Intel(R) Quartz X1000 Intel(R) Xeon(R) CPU E5-2695 v2 @ 2.40GHz Intel(R) Xeon(R) CPU E5440 @ 2.83GHz PowerPC G5 (1.1) R14000 UltraSPARC-IIIi [/bash] I should note even with the newly added Sandisk Extreme Pro SDHC card, the total time from execution to returning the results was around 10 seconds, where as on my AMD FX-8350 also hard wired it returns in less than a second. Given that also the Galileo itself is only 400mhz - you definitely won't be running a major WebAPI service on this device, but there are some definite applications (including one I will be announcing in the coming weeks).

More to come with the Galileo - I received my Intel Centrino 6235 mPCI WiFi/Bluetooth card yesterday and am just awaiting the half->full length mPCIe adapter so I can mount it properly. With any luck I will receive that today and will post on how to get WiFi working on the Galileo under Windows IoT.

Just a quick update, I just wrapped up the 0.9.850.0531 release of jcBENCH for Mac OS X/x86. Previously there was a much older port going back to January 2012, so it is nice to finally have it running on the same codebase as the other platforms now. So please if you've got an Apple product, please go run jcBENCH as I only have an older iMac to compare results with.

On a somewhat funny note the iMac I do all my Xamarin work on is several factors slower than my $60 AMD Athlon 5350 I use in my firewall - funny how technology catches up at a fraction of the cost.
Working on the Android port of jcBENCH today and ran into a question:
How to accurately detect the number of CPUs on a particular Android Device running at least Android version 4.0?

This led me to search around, I found a pretty intuitive native Java call:
Runtime.GetRuntime().AvailableProcessors(); ]]>
But this was returning 1 on my dual core Android devices. So I continued searching, one such suggestion on Stack Overflow was to count the number of files listed in the /sys/devices/system/cpu folder that began with cpu followed by a number. I ported the Java code listed in the Stack Overflow answer into C# and ran it on all 4 Android devices I own - all of them returned 3 (and looking at the actual listing only actually found a CPU0).

This got me thinking, I wonder if the traditional C# approach would work in this case? Xamarin afterall is built off of Mono....

Sure enough:
System.Environment.ProcessorCount ]]>
Returned properly on each device. Hopefully that helps someone out there.
Had an unusual experience this morning when attempting to deploy an iOS MonoTouch app to a local iMac instead of the one I had previously done over the VPN from home to my office. The Build Server Icons on the Visual Studio 2012 Command Bar were all greyed out and for the life of me I could not find a context menu to have it refresh the available build hosts. Some digging into the documentation, the actual option is under TOOLS -> Options... -> Xamarin -> iOS Settings like so: [caption id="attachment_1930" align="aligncenter" width="300"]Xamarin iOS Settings in Visual Studio 2012 Xamarin iOS Settings in Visual Studio 2012[/caption] Once on that dialog, click "Configure..." and then you'll get a dialog like so, and click on the Mac you wish to deploy to: [caption id="attachment_1931" align="aligncenter" width="300"]Xamarin iOS Build Host Xamarin iOS Build Host[/caption]