I want to use resource dictionary and app context to render a WPF GUI in PowerShell core (7.5) and .NET 9.

here is the main.xml

<Window
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Name="Window" Title="WPF Example" Height="200" Width="400">   
    <StackPanel>
        <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
            <TextBox x:Name="MyTextBox" Width="150" Style="{StaticResource TextBoxStyle}"/>
            <Button x:Name="SubmitButton" Content="Submit" Margin="5" Style="{StaticResource ButtonStyle}"/>
        </StackPanel>
    </StackPanel>
</Window>

Here is the App.Xaml

<Application
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    StartupUri="Main.xml">
    <Application.Resources>
        <Style x:Key="TextBoxStyle" TargetType="TextBox">
            <Setter Property="FontSize" Value="14"/>
            <Setter Property="Margin" Value="5"/>
        </Style>
        <Style x:Key="ButtonStyle" TargetType="Button">
            <Setter Property="Background" Value="LightBlue"/>
            <Setter Property="FontSize" Value="14"/>
            <Setter Property="Margin" Value="5"/>
        </Style>
    </Application.Resources>
</Application>

Here is the PowerShell script, all files in the same directory.

Add-Type -AssemblyName PresentationFramework

[xml]$MainXML = Get-Content -Raw -Path .Main.xml
$MainReader = New-Object -TypeName 'System.Xml.XmlNodeReader' -ArgumentList $MainXML
$MainWindow = [System.Windows.Markup.XamlReader]::Load($MainReader)

$App = [System.Windows.Application]::new()

$resourceDictionary = [System.Windows.ResourceDictionary]::new()
$resourceDictionary.Source = [System.Uri]::new("pack://application:,,,/App.xaml")

$App.Resources.MergedDictionaries.Add($resourceDictionary)

$App.MainWindow = $MainWindow

$MainWindow.Show()
$App.Run()

after running it i get this error

 $MainWindow = [System.Windows.Markup.XamlReader]::Load($MainReader)
     |  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     | Exception calling "Load" with "1" argument(s): "Provide value on 'System.Windows.StaticResourceExtension' threw an exception."
InvalidOperation:

I tried changing them, for example I tried using this XML

<Window
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Name="Window" Title="WPF Example" Height="200" Width="400">
    <Window.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
               <ResourceDictionary Source="pack://application:,,,/App.xaml"/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Window.Resources>
    <StackPanel>
        <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
            <TextBox x:Name="MyTextBox" Width="150" Style="{StaticResource TextBoxStyle}"/>
            <Button x:Name="SubmitButton" Content="Submit" Margin="5" Style="{StaticResource ButtonStyle}"/>
        </StackPanel>
    </StackPanel>
</Window>

with this PowerShell script

Add-Type -AssemblyName PresentationFramework

[xml]$MainXML = Get-Content -Raw -Path .Main.xml
$MainReader = New-Object -TypeName 'System.Xml.XmlNodeReader' -ArgumentList $MainXML
$MainWindow = [System.Windows.Markup.XamlReader]::Load($MainReader)

$App = [System.Windows.Application]::new()
$App.MainWindow = $MainWindow

$MainWindow.Show()
$App.Run()

but still getting the same error

my ultimate goal is to get this to work in PowerShell WPF GUI

https://github.com/dotnet/core/blob/main/release-notes/9.0/preview/preview4/wpf.md

which relies on this

Add-Type -Path "C:Program FilesdotnetsharedMicrosoft.WindowsDesktop.App9.0.0-preview.6.24327.6PresentationFramework.Fluent.dll"