private async void OpenEditSessionExerciseDialogAsync(SessionExercise sessionExercise)
        {
            var sessionExerciseClone = sessionExercise.Clone();

            var dialog = _dialogs.For <SessionExerciseDialogViewModel>(DialogsIdentifier);

            dialog.Data.DialogTitle       = "Modified session exercise";
            dialog.Data.SubmitButtonTitle = "Save";
            dialog.Data.SessionExercise   = SessionExerciseViewModel.FromModel(sessionExerciseClone);

            var dialogResult = await dialog.Show();

            if (dialogResult != DialogResult.Ok)
            {
                return;
            }

            sessionExerciseClone = dialog.Data.SessionExercise.ToModel();
            TrainingSession.Exercises.Replace(sessionExercise, sessionExerciseClone);
        }
        private async void OpenAddSessionExerciseDialogAsync()
        {
            var exercise = new SessionExercise();

            var dialog = _dialogs.For <SessionExerciseDialogViewModel>(DialogsIdentifier);

            dialog.Data.DialogTitle       = "New session exercise";
            dialog.Data.SubmitButtonTitle = "Create";
            dialog.Data.SessionExercise   = SessionExerciseViewModel.FromModel(exercise);

            var dialogResult = await dialog.Show();

            if (dialogResult != DialogResult.Ok)
            {
                return;
            }

            exercise = dialog.Data.SessionExercise.ToModel();
            TrainingSession.Exercises.Add(exercise);
        }