"XamlParseException in UWP class library dll

Question

I am working on a universal class library , targeted to use UWP apps.

In this am trying to use Content Dialog to get some user input.

All works good in debug, when I pack my library as dll and distribute, the ContentDialog not showing from the app which refers my dll.

I am getting Windows.UI.Xaml.Markup.XamlParseException: XAML parsing failed exception, i got this through log file.

Here is my code

ContentDialog

<ContentDialog
x:Class="xxxx.yyyy.InputContentDialogue"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Name="dialog"
Title="Title">

<ContentDialog.Resources>
    <Style x:Name="ButtonStyleNoTabFocus" TargetType="Button">
        <Setter Property="FocusVisualPrimaryBrush" Value="Transparent" />
        <Setter Property="Margin" Value="5"/>
    </Style>
</ContentDialog.Resources>

<!-- Content body -->
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}" Margin="0,20" MinWidth="550">

    <StackPanel Orientation="Vertical">

        <TextBlock  TextWrapping="WrapWholeWords" Margin="5,0,0,10">
       shkgdsakjfdhgsajkfdhkasd sadkfjahsdkj asdfjasfdja asdkfjasdf asdkjfnas asdkjfnasd
        </TextBlock>

        <TextBlock Margin="5,0,0,10">sjkdhfkjsdf sdajfakjdsb sadfkajsdfa.
        </TextBlock>

        <StackPanel Orientation="Horizontal">
            <Button  TabIndex="0" 
                 HorizontalAlignment="Center" 
                 Content="hey there"
                 Style="{StaticResource ButtonStyleNoTabFocus}" 
                 x:Name="btn1" 
                 Click="btn1_Click" 
                 GotFocus="Btn_GotFocus"
                 LostFocus="Btn_LostFocus"/>
            <Button  HorizontalAlignment="Center" 
                 Content="Hi" 
                 x:Name="btn2" 
                 Style="{StaticResource ButtonStyleNoTabFocus}" 
                 Click="btn2_Click"
                 GotFocus="Btn_GotFocus"
                 LostFocus="Btn_LostFocus"/>
            <Button  HorizontalAlignment="Center" 
                 Content="Hello" 
                 Style="{StaticResource ButtonStyleNoTabFocus}" 
                 x:Name="btn3" 
                 Click="btn3_Click" 
                 GotFocus="Btn_GotFocus"
                 LostFocus="Btn_LostFocus"/>
        </StackPanel>
    </StackPanel>
</Grid>

ContentDialog.cs

public sealed partial class InputContentDialogue : ContentDialog
{

    public UserConsentContentDialogue()
    {
        this.InitializeComponent();
        this.Result = -1;
        this.Closing += ContentDialogue_Closing;
    }


    private void ContentDialogue_Closing(ContentDialog sender, ContentDialogClosingEventArgs args)
    {
        if (args.Result == ContentDialogResult.None && this.Result == -1)
        {
            args.Cancel = true;
        }
    }

    public int Result { get; set; }


    // Handle the button clicks from dialog
    private void btn1_Click(object sender, RoutedEventArgs e)
    {

        this.Result = 0;
        // Close the dialog
        dialog.Hide();
    }

    private void btn2_Click(object sender, RoutedEventArgs e)
    {
        this.Result = 1;
        // Close the dialog
        dialog.Hide();
    }

    private void btn3_Click(object sender, RoutedEventArgs e)
    {
        this.Result = 2;
        // Close the dialog
        dialog.Hide();
    }

    private void Btn_GotFocus(object sender, RoutedEventArgs e)
    {
        Brush _blinkBrush = Application.Current.Resources["SystemControlHighlightAccentBrush"] as SolidColorBrush;
        (sender as Button).BorderBrush = _blinkBrush;
    }

    private void Btn_LostFocus(object sender, RoutedEventArgs e)
    {
        (sender as Button).BorderBrush = new SolidColorBrush(Colors.Transparent);
    }
}

And am creating a new instance and try to show the dialog , like this

 internal static async Task<int> ShowMyContentDialog()
    {
        try
        {
            InputContentDialogue dialogue = new InputContentDialogue();

            await dialogue.ShowAsync();

            return dialogue.Result;
        }
        catch(Exception e)
        {
            FileOperations.WriteToLogFile("ERROR occurred "+ e.ToString());
        }
        return -1;
    }

Everything works good , if I refer this library in code base. If I get release dll and refer it from a test app, am getting the xaml parse exception.

Can anyone help me in this.

Thanks in advance.

Answer 1

Everything works good , if I refer this library in code base. If I get release dll and refer it from a test app, am getting the xaml parse exception.

Great question, the problem is your dll file miss Xaml Content. When you compile a dll with xaml file in it, it will be recorded into xxxx.xr.xml files, and those files must be copied as well to the bin directory (BUT NOT Obj folder)of your app with relative path. After build the class library, please check if the bin folder contains dll, pdb, pri and dll resource folder like the following.

For the testing, it will work, if you directly add the dll file where in the class library bin folder to your project reference.

Answer 2

Finally, I found the solution.

Thanks @Nico for the answer, its almost answered the question.

Here is the link which gives you the clear picture about the issue

Missing xaml.xr of a class library file in UWP

Steps

1) Check "Generate library layout" in your project properties

2) While copy your dll from bin/release folder, copy these files too

• ClassLibrary1(Class Library name) Folder

  1. ClassLibrary1.xr.xml

     2.UserControl.xaml (UserControl XAML file)

• ClassLibrary1.dll

• ClassLibrary1.pri

Keep all these files in the same folder where you keep your library dll.

Just refer your library dll alone to the referrer project.

All other files will be automatically referred .