private async void IsDetailPageVisiblePropertyChanged(bool oldValue, bool newValue)
        {
            if (!oldValue && newValue)
            {
                while (ViewIsBusy)
                {
                    await Task.Delay(20);
                }
                // animate in
#pragma warning disable 4014
                DetailView.TranslateTo(0, 0, easing: Easing.CubicInOut);
                MasterView.TranslateTo(-MasterView.Width, 0, easing: Easing.CubicInOut);
#pragma warning restore 4014
            }
            else if (oldValue && !newValue)
            {
                while (ViewIsBusy)
                {
                    await Task.Delay(20);
                }
                // animate out
#pragma warning disable 4014
                DetailView.TranslateTo(MasterView.Width, 0, easing: Easing.CubicInOut);
                MasterView.TranslateTo(0, 0, easing: Easing.CubicInOut);
#pragma warning restore 4014
            }
        }