ComboBox in powershell GUI - powershell

Question

I have been building GUI's for a while in powershell with XAML. Everything has worked fine until I attempted to bring in ComboBox. Then powershell no longer accepts it.
I have built the XAML in Visual Studio and it works in Design view. Every website I go to tells me this is the right XAML code. The error occurs with the code
$reader=(New-Object System.Xml.XmlNodeReader $xaml)
try{$DiagForm=[Windows.Markup.XamlReader]::Load( $reader )}
Here is the sample I am working with. If you take out the ComboBox segment, it works perfectly fine.
function Diag {
[void][System.Reflection.Assembly]::LoadWithPartialName('presentationframework')
[xml]$XAML = #'
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Tool" Height="500" Width="300" WindowStartupLocation="CenterScreen" WindowStyle='SingleBorderWindow' ResizeMode='CanMinimize'>
<Grid>
<TextBox HorizontalAlignment="Center" Height="23" TextWrapping="Wrap" Text="Diagnostics" VerticalAlignment="Top" Width="300" Margin="0,-1,-0.2,0" TextAlignment="Center" Foreground="White" Background="#21C500"/>
<Label Content="Report" HorizontalContentAlignment="Center" HorizontalAlignment="Left" Margin="90,27,0,0" VerticalAlignment="Top" Width="120"/>
<ComboBox HorizontalAlignment="Left" Margin="90,60,0,0" VerticalAlignment="Top" Width="120">
<ComboBoxItem MouseMove="OnHover" Name="Period1" IsSelected="True">Last 24hr</ComboBoxItem>
<ComboBoxItem MouseMove="OnHover" Name="Period2" IsSelected="False">Last Week</ComboBoxItem>
<ComboBoxItem MouseMove="OnHover" Name="Period3" IsSelected="False">Last Month</ComboBoxItem>
</ComboBox>
<Label Content="Critical" HorizontalAlignment="Left" Margin="46,115,0,0" VerticalAlignment="Top"/>
<TextBox HorizontalAlignment="Left" Height="23" Margin="124,115,0,0" TextWrapping="Wrap" Text="TextBox" VerticalAlignment="Top" Width="120"/>
<Label Content="Warnings" HorizontalAlignment="Left" Margin="46,143,0,0" VerticalAlignment="Top"/>
<TextBox HorizontalAlignment="Left" Height="23" Margin="124,143,0,0" TextWrapping="Wrap" Text="TextBox" VerticalAlignment="Top" Width="120"/>
</Grid>
</Window>
'#
#Read XAML
$reader=(New-Object System.Xml.XmlNodeReader $xaml)
try{$DiagForm=[Windows.Markup.XamlReader]::Load( $reader )}
catch{Write-Host "Unable to load Windows.Markup.XamlReader. Some possible causes for this problem include: .NET Framework is missing PowerShell must be launched with PowerShell -sta, invalid XAML code was encountered."; exit}
$xaml.SelectNodes("//*[#Name]") | %{Set-Variable -Name ($_.Name) -Value $DiagForm.FindName($_.Name)}
$DiagForm.ShowDialog() | out-null
}
Diag

Answer 1

If you examine the exception that is being caught, you'll see the following error message:
Failed to create a 'MouseMove' from the text 'OnHover'.
Indeed, if you remove the MouseMove="OnHover" attributes from your XAML, the problem goes away.