Inquiry About Overriding Source Generators for [RelayCommand] Attribute

[vikher]

I’m working on a task related to updating the [RelayCommand] attribute, and I wanted to inquire about the possibility of overriding the source generators when using this attribute in the CommunityToolkit.Mvvm library.

Specifically, I’m considering a scenario where the showProgress functionality could be controlled directly via the attribute, such as:

[RelayCommand(showProgress: true)]
async Task RegisterUser()
{
    DoWork();
}

The main focus of this work item is to explore whether we can extend or modify the behavior of the [RelayCommand] attribute using parameters like showProgress without needing to manually manage it in each command.

Currently, I use the following approach, which accomplishes my desired behaviour using MVVM, without [RelayCommand] attribute .

public AsyncRelayCommand RegisterUserCommand { get; }

public RegisterViewModel()
{
    SetupAsyncRelayCommand(RegisterUser, true, false);
}

async Task RegisterUser()
{
    // Do some work
}

I was wondering if it would be possible to extend this functionality to work with a more declarative approach, similar to what I have mentioned with the [RelayCommand(showProgress: true)] pattern.

Could you share insights on whether this is feasible, or if there are existing workarounds for customizing the behavior of the [RelayCommand] attribute through source generators?