protected override void OpenDrafts()
        {
            if (_currentFragment.GetType() == typeof(BaseViewLetterFragment) &&
                !string.IsNullOrWhiteSpace(ViewLettersActivityType) &&
                ViewLettersActivityType.Equals(ViewLettersFragmentType.Drafts))
            {
                return;
            }

            ReplaceFragment(ViewLettersFragmentType.Drafts);
        }
        public override void Show(Type fragmentType)
        {
            if (currentFragement != null && currentFragement.GetType() == fragmentType)
            {
                return;
            }

            var fragment = (BaseFragment <U>)Activator.CreateInstance(fragmentType);

            SupportFragmentManager
            .BeginTransaction()
            .Replace(Resource.Id.fragment_container, fragment)
            .AddToBackStack(fragment.GetTag())
            .Commit();

            currentFragement = fragment;
        }