Error Code 0x80073CF9

After the latest build of Windows 10 mobile I noticed that my app freeze on the splash page. I tried to re-install it but it failed with the error code 0x80073CF9. I changed setting for touch and then I miraculous manage to install it. The problem with the splash still remained, so I uninstalled the app again so that I could run it in debug mode from Visual Studio. In the development environment the app worked, so I wanted to download it once more from the store. But guess…. same error code and previous workaround didn’t work. Version 2.2.2.0 is based on Silverlight which Microsoft is moving away from. Maybe the problem is related to this technology. I’m currently working on porting it to UWP but isn’t ready to release version 3.0.0.0 yet. When it comes to version 2.2.2.0 it looks like an issue that Microsoft should look into. The app worked on pervious build so to say. Will spend some time to investigate and see if I can find any solution or workarounds, but currently it looks bad for version 2.2.2.0. I hope I can release version 3.0.0.0 in August. Stay tuned!

Culture Aware Validation

It is easy to display a decimal number for any culture in .Net. The formatting support is very comprehensive and you can fine tune it in a number of different ways to suite your particular needs. But how is it to validate a string representing a decimal number from potential any culture with a wide variety of formatting rules? For example, the following strings are the same decimal value displayed according to different cultures: 1,234.56, 1.234,65, 1 234.56 and 1’234.56

In C# I can use the Parse or TryParse method of the numeric type. I tried these for decimal numbers and noticed some unexpected behavior. For the “en-US” culture the decimal separator is a dot. When parsing the string “1.2”, I received the decimal value 1.2, but when parsing “1,2” the function returned 12! I was expecting an error for this string and wonder why I received a value 10 times time greater than the one I intended to write?

After some investigation I learned that comma is the group separator and can be used in an arbitrary way, for example the string “,,,1,,,2,,,” will also be evaluated to 12. I was not so comfortable with this and from my perspective a valid decimal string should look like the formatted string you receive from, for example, the ToString method.

When the framework doesn’t give you the support you want, you have to implement it yourself. I wanted to use a regular expression to validate decimal numbers from any culture in a stricter way. The difference between different representations is the sign for decimal and group separator. .Net framework includes functions that returns current cultures signs. My solution was to create the regular expression dynamically so I could build it during runtime for the culture in use.

string groupSeparator = Thread.CurrentThread.CurrentUICulture.NumberFormat.NumberGroupSeparator;
string decimalSepartor = Thread.CurrentThread.CurrentUICulture.NumberFormat.NumberDecimalSeparator;
string regularExpression = @"^\d{1,3}([" + groupSeparator + @"]\d{3})*([" + decimalSepartor + @"]\d+)?$";

Actually, I’m a bit reluctant to create my own regular expression, since I’m not sure I know all different formats. It is also easy to make a mistake and preferable I would like to use what is include in the framework. If I find a better way, I will use it instead!

Numeric Keypad in WP 8.1

Received my first support case on my app last week. A user from Russia couldn’t create an expense. To me a bit surprising, since it has been used for a couple of years and no one else have had this issue (to my knowledge). I asked him to write down step by step what he did. When I tried the same procedure, I couldn’t re-produce the problem. It worked very well on my mobile. He mailed me a video showing exactly what he did to make the app crash. This was video was extremely helpful and I immediately suspected what the problem could be. The format of number wasn’t consistent; it was displayed with a comma as decimal separator but he entered it with a dot as decimal separator.

In the page where the problem occurs, I use TextBoxes for numeric fields. A nice feature of TextBox is that you can set the type of input with a parameter called InputScope. This property determines which keyboard layout will be used when the user enters a value. I use Number which let the user to enter values with a numeric keypad.

When have tested my app I have always had a keypad with the right sign of the decimal separator. I have tested the app in a couple of different languages but never had a keypad with wrong decimal separator (unfortunately).

My first question was how do I select which decimal separator sign should be on the keypad? I couldn’t find any API so currently I don’t know how to do it from the code (if anyone knows, please leave a comment). I found out two other ways:

  1. Change keyboard in phone settings.
    By selecting a keyboard for a language that uses another decimal separator I managed to change it.
  2. Long tap on the decimal separator.
    If you long tap the decimal sign, you get a box where you can select which sign to use. You can also select the minus sign if you want to enter a negative number.

NumericKeyLongTapBlogg

The work around for my user was to long tap and select the right decimal separator. While testing this, I realized that many of my users might very well have a keypad with the wrong decimal separator as default. I also found it a bit awkward to enter a decimal separator with long tapping, so in my next version I will simply this.

DeviceFamily

During runtime I can check which device family the application is running on with a call to:


string deviceFamily = Windows.System.Profile.AnalyticsInfo.VersionInfo.DeviceFamily;

The function seems to return a so called “magic” string and I haven’t found any list of valid values published by Microsoft. What values does it return? Is there perhaps a better alternative to figure out what device my app is running on? It’s quite important to know since I will make decisions based on the family type. I also would like some type checking during compile time to ensure that I have used a correct value.

I found a page on Microsoft site called “Guide to Universal Windows Platform (UWP) apps” that is referred to whenever I search on TargetDeviceFamily/DeviceFamily or similar. From this page I conclude that there are six families, but still not fully sure how they are identified by above function. While debugging my desktop and mobile and found out two values, “Windows.Desktop” and “Windows.Mobile”. From various sources (contradictory) on Internet, I think the following additional values are used “Windows.Team“, “Windows.IoT“, “Windows.Xbox” and “Windows.Holographic“. Haven’t found a good way to test this. Anyway, I created a utility class that returns an enumeration instead of a magic string (not sure it is 100% correct though).

public static class DeviceFamilies
{
   public static DeviceFamilyType GetCurrentDeviceFamily()
   {
      string deviceFamily = Windows.System.Profile.AnalyticsInfo.VersionInfo.DeviceFamily;

      switch (deviceFamily)
      {
         case "Windows.Desktop":
            return DeviceFamilyType.Desktop;
         case "Windows.Mobile":
            return DeviceFamilyType.Mobile;
         case "Windows.Team":
            return DeviceFamilyType.Team;
         case "Windows.IoT":
            return DeviceFamilyType.IoT;
         case "Windows.Xbox":
            return DeviceFamilyType.Xbox;
         case "Windows.Holographic":
            return DeviceFamilyType.HoloLens;
         default:
            return DeviceFamilyType.Unknown;
      }
   }
}

public enum DeviceFamilyType
{
   Desktop,
   Mobile,
   Team,
   IoT,
   Xbox,
   HoloLens,
   Unknown
}

MainPage

Much of my inspiration to the application shell comes from Microsoft’s news and financial apps. I have used them on both my mobile and desktop and like the way I interact with them. It is also very easy to create a main page with similar user experience in UWP.

The devices have different screen sizes and I want to adopt the main page depending on size available. Not sure I will support all functionality on all devices and there might be some native behavior I need to consider (for example the back button).

For the desktop client I have both space and resource available. For these devices I can offer almost all features and also make them more apparent in the UI.

MainPageDesktop

The mobile devices have smaller screens and restrictions. I need to be more selective with what features to offer and also to present the information in a way more suitable for the smaller screen size.

MainPageMobile

The SplitView control is perfect for this type of layout. There are different ways to adjust the XAML views for different screen sizes and devices.

I can use Visual State Triggers in XAML. It’s a technique to adapt the UI based on the size of the window. Another way is to use the DeviceFamily-{type} feature. In this approach I can create a particular XAML view per device family. All device specific views will share the same presentation logic (code behind).

I’m still in the beginning of this journey, but I suspect that there will be many differences between in how the views will look on each device. I also think it will be clutter to write one XAML view with a lot of state triggers adjusting it for each device family. Therefore, I decided to create a XAML view per device family (with shared presentation logic) and to separate them by a DeviceFamily folder. Source code is available here.

PrototypeSolutionExplorer

The XAML for the desktop’s MainPage is

<Page
    x:Class="UWP.Prototype.Views.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:UWP.Prototype.Views"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <Grid Background="White">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
        </Grid.RowDefinitions>
        <RelativePanel Grid.Row="0" Background="LightGray">
            <Button Name="btnNavigator" 
                    Background="LightGray"
                    FontFamily="Segoe MDL2 Assets" 
                    Content="&#xE700;" 
                    FontSize="24"
                    Margin="2,6,6,0"
                    Click="btnNavigator_Click"
                    RelativePanel.AlignLeftWithPanel="True"></Button>
            <CommandBar Name="cmdbarToolbar" RelativePanel.RightOf="btnNavigator">
                <AppBarButton Name="cmdbtnBack"  Icon="Back" Label="Back" />
                <AppBarButton Name="cmdbtnForward" Icon="Forward" Label="Forward"/>
                <AppBarSeparator Name="cmdsepNavigationCrud"></AppBarSeparator>
                <AppBarButton Name="cmdbtnRefresh" Icon="Refresh" Label="Refresh"/>
                <AppBarButton Name="cmdbtnClear" Icon="ClearSelection" Label="Clear"/>
                <AppBarButton Name="cmdbtnSave" Icon="Save"  Label="Save" />
                <AppBarButton Name="cmdbtnAdd" Icon="Add"  Label="Add" />
                <AppBarButton Name="cmdbtnEdit" Icon="Edit"  Label="Edit" />
                <AppBarButton Name="cmdbtnDelete" Icon="Delete" Label="Delete"/>
                <AppBarSeparator Name="cmdsepCrudCancel" ></AppBarSeparator>
                <AppBarButton Name="cmdbtnCancel" Icon="Cancel"  Label="Cancel"/>
            </CommandBar>
        </RelativePanel>
        <SplitView Name="spvwNavigator"
                    Grid.Row="1"  
                    DisplayMode="CompactOverlay"  
                    OpenPaneLength="200"  
                    CompactPaneLength="52"  
                    HorizontalAlignment="Left">
            <SplitView.Pane>
                <ListBox SelectionMode="Single"  
                          Name="lbNavigator">
                    <ListBoxItem Name="lbiHomePage">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock FontFamily="Segoe MDL2 Assets" FontSize="24" Margin="0,0,0,0" Text="&#xE10F;" />
                            <TextBlock Text="Home" FontSize="20" Margin="20,0,0,2" />
                        </StackPanel>
                    </ListBoxItem>
                    <ListBoxItem Name="lbiEventPage">
                        <StackPanel Orientation="Horizontal">
                            <Image Source="/Assets/EventIcon.png" Height="Auto" Width="24" Margin="0,0,0,0" HorizontalAlignment="Left"></Image>
                            <TextBlock Text="Event" FontSize="20" Margin="20,0,0,0" />
                        </StackPanel>
                    </ListBoxItem>
                    <ListBoxItem Name="lbiAboutPage">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock FontFamily="Segoe MDL2 Assets" FontSize="24" Margin="0,0,0,0" Text="&#xE171;" />
                            <TextBlock Text="About" FontSize="20" Margin="20,0,0,0" />
                        </StackPanel>
                    </ListBoxItem>
                    <ListBoxItem Name="lbiBuyPage">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock FontFamily="Segoe MDL2 Assets" FontSize="24" Margin="0,0,0,0" Text="&#xE719;" />
                            <TextBlock Text="Buy" FontSize="20" Margin="20,0,0,0" />
                        </StackPanel>
                    </ListBoxItem>
                </ListBox>
            </SplitView.Pane>
            <SplitView.Content>
                <Frame Name="frmContent">
                </Frame>
            </SplitView.Content>
        </SplitView>
    </Grid>
</Page>

The XAML for the mobile’s MainPage is very similar. The risk with current approach is obliviously a lot of duplicated code, and I need to write more code before I really know the best way to design the views. A view per device family or many visual state triggers….

<Page
    x:Class="UWP.Prototype.Views.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:UWP.Prototype.Views"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">
    <Page.BottomAppBar>
        <CommandBar Name="cmdbarToolbar" RelativePanel.RightOf="btnNavigator">
            <AppBarButton Name="cmdbtnSave" Icon="Save"  Label="Save" />
            <AppBarButton Name="cmdbtnAdd" Icon="Add"  Label="Add" />
            <AppBarButton Name="cmdbtnEdit" Icon="Edit"  Label="Edit" />
            <AppBarButton Name="cmdbtnDelete" Icon="Delete" Label="Delete"/>
            <AppBarButton Name="cmdbtnCancel" Icon="Cancel"  Label="Cancel"/>
        </CommandBar>
    </Page.BottomAppBar>

    <Grid Background="White">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
        </Grid.RowDefinitions>
        <RelativePanel Grid.Row="0" Background="LightGray">
            <Button Name="btnNavigator" 
                    Background="LightGray"
                    FontFamily="Segoe MDL2 Assets" 
                    Content="&#xE700;" 
                    FontSize="24"
                    Margin="0,0,0,0"
                    Click="btnNavigator_Click"
                    RelativePanel.AlignLeftWithPanel="True"></Button>
        </RelativePanel>
        <SplitView Name="spvwNavigator"  
                    Grid.Row="1"  
                    DisplayMode="Overlay"  
                    OpenPaneLength="200"  
                    CompactPaneLength="56"  
                    HorizontalAlignment="Left">
            <SplitView.Pane>
                <ListBox SelectionMode="Single"  
                          Name="lbNavigator">
                    <ListBoxItem Name="lbiHomePage">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock FontFamily="Segoe MDL2 Assets" FontSize="24" Margin="0,0,0,0" Text="&#xE10F;" />
                            <TextBlock Text="Home" FontSize="20" Margin="20,0,0,2" />
                        </StackPanel>
                    </ListBoxItem>
                    <ListBoxItem Name="lbiEventPage">
                        <StackPanel Orientation="Horizontal">
                            <Image Source="/Assets/EventIcon.png" Height="Auto" Width="24" Margin="0,0,0,0" HorizontalAlignment="Left"></Image>
                            <TextBlock Text="Event" FontSize="20" Margin="20,0,0,0" />
                        </StackPanel>
                    </ListBoxItem>
                    <ListBoxItem Name="lbiAboutPage">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock FontFamily="Segoe MDL2 Assets" FontSize="24" Margin="0,0,0,0" Text="&#xE171;" />
                            <TextBlock Text="About" FontSize="20" Margin="20,0,0,0" />
                        </StackPanel>
                    </ListBoxItem>
                    <ListBoxItem Name="lbiBuyPage">
                        <StackPanel Orientation="Horizontal">
                            <TextBlock FontFamily="Segoe MDL2 Assets" FontSize="24" Margin="0,0,0,0" Text="&#xE719;" />
                            <TextBlock Text="Buy" FontSize="20" Margin="20,0,0,0" />
                        </StackPanel>
                    </ListBoxItem>
                </ListBox>
            </SplitView.Pane>
            <SplitView.Content>
                <Frame Name="frmContent">
                </Frame>
            </SplitView.Content>
        </SplitView>
    </Grid>
</Page>

Mobilize.NET

From the build event earlier this year I heard about a tool, Mobilize.NET, too relieve the work load to migrate an app from Silverlight to UWP. There is a good web cast from channel 9 about it at https://channel9.msdn.com/Events/Build/2016/P498. I really liked the idea even though I suspected that the tool wouldn’t be able to convert so much of my app. But just to get some help with some well-known common tasks sounded very helpful. So I installed it and gave it a try.

There were many issues reported and it would take very long time to sort things out (if even doable). As I looked through the converted code I realized that I’m just trying to port the code. My current implementation is just intended as an app for windows phone. It’s not designed as a universal app capable of running on several different devices.

I wanted to change this! Instead of just porting my “windows phone 8.1-ish” user interface to the universal windows platform. I wanted to re-design it so it becomes “universal-ish” and able to run on several different devices, primarily desktops and phones. Also, cross-platform in the long run.

Didn’t get so much help from Mobilize.NET and now my next challenge is to find a universal user interface, easy to use, implement and maintain for all different kind of devices…. Let’s see what I will end up with.

AutoMapper 5.0.2

I’m migrating my app from Silverlight to UWP. At the same time, I’m changing from VS 2013 to VS 2015. It was a while since I worked with the app and noticed that there where a new version of AutoMapper available in Nuget Package Manager, but I couldn’t install it. I tried to find a solution on the Internet, but didn’t find any. After several hours of struggling, I managed to install it after removing the contents of both bin and obj folders from all projects in my solution. I tried several times to just remove from bin, but wasn’t enough.

Upgrade to NHibernate 3.0.0

I recently upgraded to NHibernate 3.0.0. NHibernate 3.0.0 has a good backward compatible with version 2.1.2. It includes a new Linq provider that fully supports Linq. When upgrading to NHibernate 3.0.0 I stumble into the following issues:

· The new Linq provider is included in NHibernat 3.0.0 and I didn’t have to download it separately.

· The method session.Linq<T>() is replaced by session.Query<T>().

· The new Linq provider has full support for Linq and I had to update some Linq queries. For example, it manages eager load differently. It includes new methods, Fetch and FetchMany, to define what shall be fetched eagerly.

So, it was quite easy to upgrade and I didn’t have that much trouble. Still need to explore all new features and re-factor the code whenever possible to take advantage of them. First impression of NH 3.0.0 is very good.

IE crashes when opening document in Sharepoint

For some reason my browser started to crash when I tried to open documents in Sharepoint. After some investigation I found out that I had multiple versions of an assembly called Owssupp.dll confusing IE. One version from Office 2003 and another from Office 2007. The later one was installed while evaluating Onenote 2007. I solved the problem by uninstalling Onenote 2007. I found a link that describes the problem http://geekswithblogs.net/redwards/archive/2007/06/18/113287.aspx. Additional information can be found here http://support.microsoft.com/kb/833714.

Exception has been thrown by the target of invocation

I was leading a lab today. The first exercise has a starting solution with some basic code that you are suppose to enhance during the implementation. One of the very first thing you shall do is to run the unit tests to make sure that the code works. It has always worked! That is, until today. One of the participants couldn’t execute any of unit tests. Visual Studio kept on displaying the same error message for every attempt to run any of the unit tests: “Exception has been thrown by the target of invocation”.

We searched on the Internet and found many suggestions on what might cause the problem. Finally we found out that the reason was that his development environment wasn’t connected to TFS. The lab is of course checked into TFS and there is a bug in VS 2008 that causes this problem if you open a bounded solution in a studio disconnected from TFS (http://blogs.msdn.com/b/shitals/archive/2009/12/31/9942725.aspx).