XAML editor indicates DataContext does not support view model's type about fsharp.viewmodule

[ReedCopsey]

I'm fairly certain this is a regression in Visual Studio's XAML editor itself, not related to FSharp.ViewModule. I've seen this (and some other oddities), but have no idea why that'd even be possible as an error message.

DataContext is typed as System.Object, so anything should be a valid DataContext.

[allykzam]

I had assumed the same when I wrote this up. Don't suppose you know a place I could report this to the VS people without it being ignored or wontfix'd?

[ReedCopsey]

Closing because it's out of my hands - hopefully VS will fix.

[FuNkNaN]

There's a workaround to avoid the error.

In the xaml.fs file add

type Wrapper() =
    member __.ViewModel = MainViewModel()

Then in the xaml file change

<Window.DataContext>
    <local:MainViewModel/>
</Window.DataContext>

to

<Window.Resources>
    <ResourceDictionary>
        <local:Wrapper x:Key="Wrapper"/>
        <!--
            Other resources
        -->
    </ResourceDictionary>
</Window.Resources>
<Window.DataContext>
    <Binding Source="{StaticResource Wrapper}" Path="ViewModel"/>
</Window.DataContext>

Seems to resolve the issue at design time. Hope it helps.