I'm experimenting with WinUI 3 and trying to create a basic user interface.
As soon as I add a MenuBar control, I get a Microsoft.UI.Xaml.Markup.XamlParseException: 'XAML parsing failed.' at the InitializeComponent() line of that view's code-behind when trying to start the app.
I can add other controls without issues, but MenuBar always seems to break the app. What am I missing?
Check your App.xaml to include the <XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" /> resource dictionary like this:
<Application
x:Class="Your.Project.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<!-- the following line is important -->
<XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
</Application>
Related
Before, in .NET Framework, when I created a WPF class library, I had my App.xaml (set as Application definition) referencing my resource dictionaries like that:
<Application xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="ResourceDictionary1.xaml" />
<ResourceDictionary Source="ResourceDictionary2.xaml" />
<ResourceDictionary Source="ResourceDictionary3.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
</Application>
However, now, with .NET 5, I get this compilation error:
Library project file cannot specify ApplicationDefinition element.
So that message means I can't have an App.xaml file in a class library anymore. But now, I don't know how to define my resources globally in a class library. Isn't there any way to do this without referencing the dictionaries in each and every XAML file in the project?
Edit: It's not about the Source syntax. The path is correct and everything compiles perfectly if I set the project to Windows Application instead of Class Library.
refering to that github issue : https://github.com/dotnet/wpf/issues/2812#issuecomment-607537794
In an SDK style WindowsDesktop project,
*.xaml are all treated as Page items by default, unless they are named App.xaml (C#) or Application.xaml (VB).
App.xaml/Application.xaml is treated as ApplicationDefinition by default.
<!--
Disables automatic globbing of App.xaml/Application.xaml into
ApplicationDefinition item
App.xaml/Application.xaml would now get treated as any other *.xaml file
(typically, a Page)
-->
<PropertyGroup>
<EnableDefaultApplicationDefinition>false</EnableDefaultApplicationDefinition>
</PropertyGroup>
Worth a try.
For me works the following: If you have library-project with resources (i.e. namespace "Project.Resources") and have presentation-project (i.e. namespace "Project.Presentation"):
<Application x:Class="Project.Presentation.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="/Project.Resources;Dictionary.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
</Application>
Don't forget to add reference to "Project.Resources" in "Project.Presentation".
How can I use a (merged) WPF Resource Dictionary in a C# class library project?
Here is what I did:
In my C# class library project I have a file Dictionary1.xaml like that:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
>
<Style x:Key="PluginFrameBorderStyle">
...
</Style>
</ResourceDictionary>
Then, I have a UserControl file UserControl1.xaml where I try to use the Dictionary like that:
<UserControl x:Class="EditorPackageA.BackboneMemberB1Editor.BackboneMemberB1Editor"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
xmlns:local="clr-namespace:EditorPackageA.EditorBase"
xmlns:prism="http://www.codeplex.com/prism" d:DesignWidth="690.4" d:DesignHeight="460.12">
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="/Dictionary1.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</UserControl.Resources>
...
</UserControl>
The project compiles but at runtime I get the error:
with the exception detail:
The same approach works when applied within a WPF project rather than a Class Library project.
What might be the solution here?
Important Addendum:
During design-time I see the effect of the used style that is embedded via the ResourceDictionary, hence the URI of the style and the dictionary must be correct!?
Try to use so called pack URI. I think that you have to explicitly specify where the resource dictionary is located.
<ResourceDictionary Source="pack://application:,,,/TheNameOfClassLibrary;component/Dictionary1.xaml"/>
In the case of a WPF project your approach works because WPF engine by default looks for resource in the assembly being executed (in exe).
You should refer/link the ResourceDictionary xml file to the Source attribute with assembly and component name.
Use relative path as follows:
<ResourceDictionary Source="../Dictionary1.xaml" />
If it is not working, then try PACK URL
<ResourceDictionary Source="pack://application:,,,/Your.Base.AssemblyName;component/DictionaryFolder/Dictionary1.xaml" />
Hope it helps you
You probably need to merge your library's resource dictionary in your application resources. You need to edit your App.xaml file and add something like:
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="pack://application:,,,/YourAssembly;component/Dictionary1.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
In codeplex's mui, the app.xaml goes like this
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="/FirstFloor.ModernUI;component/Assets/ModernUI.xaml" />
<ResourceDictionary Source="/FirstFloor.ModernUI;component/Assets/modernui.light.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
but how can I choose the FirstFloor.ModernUI;component/Assets/modernui.light.xaml" in replace of FirstFloor.ModernUI;component/Assets/modernui.light.xaml" in code behind every time I run the program?
The ModernUI source code comes with a sample application that shows you how to do exactly what you ask.
The library has an AppearanceManager class. Set the current instance ThemeSource property:
AppearanceManager.Current.ThemeSource = AppearanceManager.LightThemeSource;
My WPF applications are reaching the level of complexity at which it becomes desirable to place some of the code and other resources inside a Reference file (*.dll).
I am sure I can figure out how to do this, by following the myriad applications out there.
In this particular case, however, the files are two, XAML:
Can somebody please provide an example on how to expose or publish the XAML resources? Are *.cs files required?
TIA
The XAML file outlined by #HighCore should look like this:
<Application x:Class="Application"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" >
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="pack://application:,,,/ReferencedAssembly;component/Subfolder/ResourceFile.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
</Application>
XAML ResourceDictionaries do not generate classes. I'm not sure why you would expect such thing.
Simply move the needed ResourceDictionary definitions to a separate assembly then use the Pack URI Syntax to merge these resources to your application's Resources in app.xaml:
<Application ....>
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="pack://application:,,,/ReferencedAssembly;component/Subfolder/ResourceFile.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
</Application>
I have an ObjectDataProvider declared on a dictionary:
<ObjectDataProvider x:Key="Resources"
ObjectType="{x:Type const:CultureResources}"
MethodName="GetResourceInstance"/>
And I have a class that wants to find it like this:
m_provider = (ObjectDataProvider) App.Current.FindResource("Resources");
But when it tries to find the Resource, it launches the error
ResourceReferenceKeyNotFoundException
And can't find my resource... Here you have an image on how my project is divided:
The Default.xaml is my default dictionary.
So, why I can't find my Resources element defined on my dictionary?
I need to answer my question, because it was such a weird thing...
At first, I need to say that I had to add my Dictionary.xaml to my App.xaml:
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="../themes/Default.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>
For some reason, it wasn't enough to call it on my MainWindow.xaml. So I erased it from my MainWindow.xaml and added it to App.xaml, but I couldn't have them inserted in both sides. That was the part that I couldn't see clearly...