Commands¶

Prefer binding user interactions to commands rather than methods.

Do¶

// In the view
this.BindCommand(ViewModel, vm => vm.DeleteCommand, v => v.deleteButton);

public class RepositoryViewModel : ReactiveObject
{
  public RepositoryViewModel()
  {
    DeleteCommand = ReactiveCommand.CreateFromObservable(DeleteImpl);
    DeleteCommand.ThrownExceptions.Subscribe(ex => /*...*/);
  }

  public ReactiveCommand<Unit, Unit> DeleteCommand { get; }

  private IObservable<Unit> DeleteImpl() {...}
}

Don't¶

Use the Caliburn.Micro conventions for associating buttons and commands:

// In XAML
<Button x:Name="Delete" .../>

public class RepositoryViewModel : PropertyChangedBase
{
  public void Delete() {...}    
}

Why?¶

ReactiveCommand exposes the CanExecute property of the command to enable applications to introduce additional behavior.
It handles marshaling the result back to the UI thread.
It tracks in-flight items.