MVVM Toolkit error MVVMTK0043

Properties annotated with [ObservableProperty] must be partial properties with a getter and a setter that is not init-only.

The following sample generates MVVMTK0043:

using CommunityToolkit.Mvvm.ComponentModel;

namespace MyApp;

public partial class SampleViewModel : ObservableObject
{
    [ObservableProperty]
    public partial string? Name { get; }
}

You should ensure that properties have both a get and a set accessor, like so:

using CommunityToolkit.Mvvm.ComponentModel;

namespace MyApp;

public partial class SampleViewModel : ObservableObject
{
    [ObservableProperty]
    public partial string? Name { get; set; }
}

Additional resources

• You can find more examples in the unit tests.