public Pomodoro(IUserInterface ui, ISettings settings) { Duration = settings.PomodoroDuration.ToString(); Begin = new DelegateCommand( canExecute: _ => !_inProgress, execute: _ => { _inProgress = true; Begin.RaiseCanExecuteChanged(); Progress.Start(); }); Progress = new ProgressTimer(ui, settings.PomodoroDuration, onComplete: () => { _inProgress = false; Begin.RaiseCanExecuteChanged(); ui.TransitionToPage <Break>(); }); }