Category Archives: Tools

Using PowerShell to automate the build process of your Windows Phone app

Another day another occasion to share a tip which comes with the development of my todo-list app 2Day. This time, I share a small PowerShell script I use in order to build the application. Of course the script will not work out of the box for you but it could be useful if you’re thinking about automating the generation of your application.

Background: managing multiple versions

Since release 1.5.0 there are two versions of 2Day: the lite version (free) and the standard version (paid). I switch from one configuration to another using two Build Configurations. When I want to build the Lite version I build using the Release Lite configuration while for the standard version I build in Release. The difference between the two is a conditional symbol.


I also have a WP7 and a WP8. So for each official release, I must produce 4 XAPs:

  • WP7 Lite
  • WP7 Full
  • WP8 Lite
  • WP8 Full

This is the reason why I was thinking about automating this stuff !

PowerShell script

The script itself is very straightforward: I use MSBuild to build the Visual Studio Solution File (*.sln) using the 2 configurations I described earlier. Once a build is complete I move the generated XAPs to an output folder. As I said this script will NOT work out of the box for your but it could be used as an example. Here is the code:

# usage is ./ScripName -version 1.5.0
param([string]$version = "version")

$solution = "2Day.sln"
$msbuild = "C:\Windows\Microsoft.NET\Framework\v4.0.30319\MSBuild.exe"
# get the location of the script
$rootDir = [System.Io.Path]::GetDirectoryName($MyInvocation.MyCommand.Path)
# build the location of the sln file. In my case this is under /Branches/WindowsPhone/versionunmber/
$baseDir = $rootDir + "\Branches\WindowsPhone\" + $version + "\"
# and the ouput is in a Build folder
$outputFolder = $rootDir + "\Build\"

# if the output folder exists, delete it
if ([System.IO.Directory]::Exists($outputFolder))
 [System.IO.Directory]::Delete($outputFolder, 1)
 [System.IO.Directory]::CreateDirectory($outputFolder) | Out-Null
 [System.IO.Directory]::CreateDirectory($outputFolder)| Out-Null

Write-Host "Building 2Day version: " $version
Write-Host "Solution is at: "  $baseDir$solution

# make sure our working directory is correct
cd $baseDir

$configurations = "Release", "Release Lite"
foreach($configuration in $configurations)
	# prepare build command line
	$options = "/noconsolelogger /m /p:Configuration=""" + $configuration + """ /p:Platform=""Any CPU"""

	# prepare output path
	$releasePath1 = $baseDir + "2Day.App.WP7\bin\" + $configuration + "\_2DayWP7.xap"
	$outFile1 = "2Day_" + $version + "_WP7_" + $configuration.Replace(" ", "_") + ".xap"
	$releasePath2 = $baseDir + "2Day.App.WP8\bin\" + $configuration + "\_2DayWP8.xap"
	$outFile2 = "2Day_" + $version + "_WP8_" + $configuration.Replace(" ", "_") + ".xap"
	# clean
	Write-Host Perform cleaning...	
	$clean = $msbuild + " " + $solution + " " + $options + " /t:Clean"
	Invoke-Expression $clean | Out-Null
	# build
	Write-Host "Building with configuration"$configuration"..."
	$build = $msbuild + " " + $solution + " " + $options + " /t:Build"
	Invoke-Expression $build | Out-Null
	# move the files that were built to the output folder
	$out1 = $outputFolder + $outFile1;
	$out2 = $outputFolder + $outFile2;
	[System.IO.File]::Copy($releasePath1, $out1)
	[System.IO.File]::Copy($releasePath2, $out2)
	Write-Host "Output: " $out1 $out2

cd $rootDir
Write-Host "Done"

A Reactive Extension (Rx) use case in a Windows Phone app

While working on my todo-list application 2Day, I encountered a situation where Rx came to the rescue. Rx (Reactive Extension) is a framework which has been available for a couple of years now. It is possible to use it on the phone very easily. In this blog post, I share a piece of code which use Rx to implement a specific feature in 2Day.

2Day’s users have requested a search feature. The idea is simple: give the user a new page where he can type some text which then filters his tasks. Here is the feature in action in 2Day:

2Day - global search

Even though it seems very basic, I wanted to add an extra feature: perform the search a couple of milliseconds after the user actually stops typing. This prevents the search result to blink while the user types. It turns out it’s very easy to implement this using Rx which is dedicated to manipulate stream of observable items. Here is the code:

var seq = Observable
    .FromEventPattern(this.textbox, "TextChanged")
    .Subscribe(e =>
        this.viewmodel.SearchText = this.textbox.Text;

The first step is to create the observable sequence using the FromEventPattern method which can turn an event into an observable stream. Then the Throttle method allows to “calm down” the stream, by requiring the specified amount of time to be spent before sending the item in the output stream.

This can be shown using the following diagram:


If the user presses quickly the letters “p”, “a”, “i” and “r” we will start the search only after the specified amount of time and not for each new letter. Notice that the subscribe method does not do a lot of things: it only sets a property on the ViewModel layer which actually performs the search.

Here is a simple yet useful use case for Rx. It’s very nice to have the library available out of the box on the phone. Hope it helps 🙂

Welcome 2013 :-)

This is the perfect time to take a look at what happened in the last few months as well as what’s on the roadmap for next year. So let’s start by taking a look at 2012…



  • In November, I gave a presentation about Windows Phone 8 at SFEIR Plays

sfeir plays

Blog posts

The last year I blogged mostly about Windows Phone stuff. This is not a surprise as I’m busy (on my personal time…) working for my 2Day todo-list application. I’m finalizing a major release that should be submitted to the marketplace soon with a ton of new features and improvement (several blog posts should highlight some topics from a developer point of view).

Here is the full list of article (oldest first):

Next year

2013 should very busy too 🙂

  • In mid-February, I will speak again during the TechDays in Paris. The topic is the same as last year: performance optimization for Windows Phone applications. However, with Windows Phone 8 we’ve plenty of new topics to cover !
  • In late-February I will fly to Redmond for the MVP Summit 2013. It will be my sedond time there. As aways, all the content will be under NDA… I will share a room with my friend Jose Fajardo I met at //BUILD/ 2011 !
  • In March, I should setup an event with my company and Microsoft in Grenoble talking about Windows 8 and Windows Phone 8

I’m still deeply invested with 2Day so hopefully you should see more tips and tricks about Windows Phone. As a Windows 8 version is also on its way, that should give me many reasons to write new blog posts.

Happy new year dear readers !