Calendar stuff.

Wino.Calendar.ViewModels/CalendarAppShellViewModel.cs

@@ -99,6 +99,7 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
         {
             Messenger.Send(new CalendarDisplayTypeChangedMessage(StatePersistenceService.CalendarDisplayType));
 
+            UpdateDateNavigationHeaderItems();
 
             // Change the calendar.
             DateClicked(new CalendarViewDayClickedEventArgs(GetDisplayTypeSwitchDate()));
@@ -253,8 +254,6 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
                 break;
             case CalendarDisplayType.Month:
                 break;
-            case CalendarDisplayType.Year:
-                break;
             default:
                 break;
         }
@@ -320,49 +319,88 @@ public partial class CalendarAppShellViewModel : CalendarBaseViewModel,
     /// </summary>
     private void UpdateDateNavigationHeaderItems()
     {
-        DateNavigationHeaderItems.Clear();
+        var settings = PreferencesService.GetCurrentCalendarSettings();
+        var cultureInfo = settings.CultureInfo ?? CultureInfo.CurrentUICulture;
 
-        // TODO: From settings
+        var visibleRange = HighlightedDateRange ?? new DateRange(DateTime.Today, DateTime.Today.AddDays(1));
-        var testInfo = new CultureInfo("en-US");
+        var headerText = GetHeaderText(visibleRange, cultureInfo);
+
+        DateNavigationHeaderItems.ReplaceRange([headerText]);
+        SelectedDateNavigationHeaderIndex = DateNavigationHeaderItems.Count > 0 ? 0 : -1;
+    }
+
+    private string GetHeaderText(DateRange visibleRange, CultureInfo cultureInfo)
+    {
+        var startDate = visibleRange.StartDate.Date;
+        var endDate = visibleRange.EndDate.Date > startDate ? visibleRange.EndDate.Date.AddDays(-1) : startDate;
 
         switch (StatePersistenceService.CalendarDisplayType)
         {
             case CalendarDisplayType.Day:
+                return startDate.ToString("MMMM d, dddd", cultureInfo);
             case CalendarDisplayType.Week:
             case CalendarDisplayType.WorkWeek:
+                if (startDate.Month == endDate.Month && startDate.Year == endDate.Year)
+                {
+                    return $"{startDate.ToString("MMMM d", cultureInfo)} - {endDate.ToString("%d", cultureInfo)}";
+                }
+
+                return $"{startDate.ToString("MMMM d", cultureInfo)} - {endDate.ToString("MMMM d", cultureInfo)}";
             case CalendarDisplayType.Month:
-                DateNavigationHeaderItems.ReplaceRange(testInfo.DateTimeFormat.MonthNames);
+                return GetDominantMonthHeaderText(startDate, endDate, cultureInfo);
-                break;
-            case CalendarDisplayType.Year:
-                break;
             default:
-                break;
+                return startDate.ToString("d", cultureInfo);
         }
-
-        SetDateNavigationHeaderItems();
     }
 
-    partial void OnHighlightedDateRangeChanged(DateRange value) => SetDateNavigationHeaderItems();
+    private static string GetDominantMonthHeaderText(DateTime startDate, DateTime endDate, CultureInfo cultureInfo)
-
-    private void SetDateNavigationHeaderItems()
     {
-        if (HighlightedDateRange == null) return;
+        if (endDate < startDate)
-
-        if (DateNavigationHeaderItems.Count == 0)
         {
-            UpdateDateNavigationHeaderItems();
+            endDate = startDate;
         }
 
-        // TODO: Year view
+        var monthDayCounts = new Dictionary<(int Year, int Month), int>();
-        var monthIndex = HighlightedDateRange.GetMostVisibleMonthIndex();
 
-        SelectedDateNavigationHeaderIndex = Math.Max(monthIndex - 1, -1);
+        for (var day = startDate; day <= endDate; day = day.AddDays(1))
+        {
+            var key = (day.Year, day.Month);
+
+            if (monthDayCounts.TryGetValue(key, out var count))
+            {
+                monthDayCounts[key] = count + 1;
+            }
+            else
+            {
+                monthDayCounts[key] = 1;
+            }
+        }
+
+        var dominantKey = (Year: startDate.Year, Month: startDate.Month);
+        var dominantCount = -1;
+
+        foreach (var pair in monthDayCounts)
+        {
+            if (pair.Value > dominantCount)
+            {
+                dominantCount = pair.Value;
+                dominantKey = pair.Key;
+            }
+        }
+
+        return new DateTime(dominantKey.Year, dominantKey.Month, 1).ToString("Y", cultureInfo);
     }
 
+    partial void OnHighlightedDateRangeChanged(DateRange value) => UpdateDateNavigationHeaderItems();
+
     public async void Receive(CalendarEnableStatusChangedMessage message)
         => await ExecuteUIThread(() => IsCalendarEnabled = message.IsEnabled);
 
     public void Receive(NavigateManageAccountsRequested message) => SelectedMenuItemIndex = 1;
 
-    public void Receive(CalendarDisplayTypeChangedMessage message) => OnPropertyChanged(nameof(IsVerticalCalendar));
+    public void Receive(CalendarDisplayTypeChangedMessage message)
+    {
+        OnPropertyChanged(nameof(IsVerticalCalendar));
+        UpdateDateNavigationHeaderItems();
+    }
 }

Wino.Calendar.ViewModels/CalendarPageViewModel.cs

@@ -232,7 +232,14 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
     {
         base.OnNavigatedTo(mode, parameters);
 
-        if (mode == NavigationMode.Back) return;
+        if (mode == NavigationMode.Back)
+        {
+            // We unregister recipients on navigate-away, so mutations that happened while this page
+            // was not active (e.g. CalendarItemDeleted from details page) can be missed.
+            // Rehydrate currently visible ranges to guarantee UI and DB are consistent on return.
+            _ = RefreshVisibleRangesAsync();
+            return;
+        }
 
         RefreshSettings();
 
@@ -682,6 +689,34 @@ public partial class CalendarPageViewModel : CalendarBaseViewModel,
         }
     }
 
+    private async Task RefreshVisibleRangesAsync()
+    {
+        try
+        {
+            await _calendarLoadingSemaphore.WaitAsync().ConfigureAwait(false);
+
+            if (DayRanges == null || DayRanges.Count == 0)
+                return;
+
+            RefreshSettings();
+
+            foreach (var dayRange in DayRanges)
+            {
+                await InitializeCalendarEventsForDayRangeAsync(dayRange).ConfigureAwait(false);
+            }
+
+            FilterActiveCalendars(DayRanges);
+        }
+        catch (Exception ex)
+        {
+            Log.Error(ex, "Failed to refresh calendar ranges after navigation back.");
+        }
+        finally
+        {
+            _calendarLoadingSemaphore.Release();
+        }
+    }
+
     private async Task TryConsolidateItemsAsync()
     {
         // Check if trimming is necessary

Wino.Calendar/Controls/CustomCalendarFlipView.cs

@@ -1,5 +1,7 @@
-using Windows.UI.Xaml.Automation.Peers;
+using Windows.UI.Xaml;
+using Windows.UI.Xaml.Automation.Peers;
 using Windows.UI.Xaml.Controls;
+using Wino.Core.Domain.Enums;
 
 namespace Wino.Calendar.Controls;
 
@@ -8,35 +10,73 @@ namespace Wino.Calendar.Controls;
 /// </summary>
 public partial class CustomCalendarFlipView : FlipView
 {
-    private const string PART_PreviousButton = "PreviousButtonHorizontal";
+    private const string PART_PreviousButtonHorizontal = "PreviousButtonHorizontal";
-    private const string PART_NextButton = "NextButtonHorizontal";
+    private const string PART_NextButtonHorizontal = "NextButtonHorizontal";
+    private const string PART_PreviousButtonVertical = "PreviousButtonVertical";
+    private const string PART_NextButtonVertical = "NextButtonVertical";
 
-    private Button PreviousButton;
+    public static readonly DependencyProperty DisplayTypeProperty = DependencyProperty.Register(
-    private Button NextButton;
+        nameof(DisplayType),
+        typeof(CalendarDisplayType),
+        typeof(CustomCalendarFlipView),
+        new PropertyMetadata(CalendarDisplayType.Week));
+
+    public CalendarDisplayType DisplayType
+    {
+        get => (CalendarDisplayType)GetValue(DisplayTypeProperty);
+        set => SetValue(DisplayTypeProperty, value);
+    }
+
+    private Button PreviousButtonHorizontal;
+    private Button NextButtonHorizontal;
+    private Button PreviousButtonVertical;
+    private Button NextButtonVertical;
 
     protected override void OnApplyTemplate()
     {
         base.OnApplyTemplate();
 
-        PreviousButton = GetTemplateChild(PART_PreviousButton) as Button;
+        PreviousButtonHorizontal = GetTemplateChild(PART_PreviousButtonHorizontal) as Button;
-        NextButton = GetTemplateChild(PART_NextButton) as Button;
+        NextButtonHorizontal = GetTemplateChild(PART_NextButtonHorizontal) as Button;
+        PreviousButtonVertical = GetTemplateChild(PART_PreviousButtonVertical) as Button;
+        NextButtonVertical = GetTemplateChild(PART_NextButtonVertical) as Button;
 
         // Hide navigation buttons
-        PreviousButton.Opacity = NextButton.Opacity = 0;
+        HideButton(PreviousButtonHorizontal);
-        PreviousButton.IsHitTestVisible = NextButton.IsHitTestVisible = false;
+        HideButton(NextButtonHorizontal);
+        HideButton(PreviousButtonVertical);
+        HideButton(NextButtonVertical);
+    }
 
-        var t = FindName("ScrollingHost");
+    private static void HideButton(Button button)
+    {
+        if (button == null) return;
+
+        button.Opacity = 0;
+        button.IsHitTestVisible = false;
     }
 
     public void GoPreviousFlip()
     {
-        var backPeer = new ButtonAutomationPeer(PreviousButton);
+        var previousButton = DisplayType == CalendarDisplayType.Month
+            ? PreviousButtonVertical ?? PreviousButtonHorizontal
+            : PreviousButtonHorizontal ?? PreviousButtonVertical;
+
+        if (previousButton == null) return;
+
+        var backPeer = new ButtonAutomationPeer(previousButton);
         backPeer.Invoke();
     }
 
     public void GoNextFlip()
     {
-        var nextPeer = new ButtonAutomationPeer(NextButton);
+        var nextButton = DisplayType == CalendarDisplayType.Month
+            ? NextButtonVertical ?? NextButtonHorizontal
+            : NextButtonHorizontal ?? NextButtonVertical;
+
+        if (nextButton == null) return;
+
+        var nextPeer = new ButtonAutomationPeer(nextButton);
         nextPeer.Invoke();
     }
 }

Wino.Calendar/Controls/DayColumnControl.cs

@@ -1,6 +1,9 @@
-using System;
+using System;
+using System.Collections.Specialized;
+using System.Linq;
 using Windows.UI.Xaml;
 using Windows.UI.Xaml.Controls;
+using Wino.Core.Domain.Collections;
 using Wino.Core.Domain.Models.Calendar;
 
 namespace Wino.Calendar.Controls;
@@ -10,7 +13,6 @@ public partial class DayColumnControl : Control
     private const string PART_HeaderDateDayText = nameof(PART_HeaderDateDayText);
     private const string PART_IsTodayBorder = nameof(PART_IsTodayBorder);
     private const string PART_ColumnHeaderText = nameof(PART_ColumnHeaderText);
-
     private const string PART_AllDayItemsControl = nameof(PART_AllDayItemsControl);
 
     private const string TodayState = nameof(TodayState);
@@ -20,6 +22,7 @@ public partial class DayColumnControl : Control
     private TextBlock ColumnHeaderText;
     private Border IsTodayBorder;
     private ItemsControl AllDayItemsControl;
+    private CalendarEventCollection _boundEventsCollection;
 
     public CalendarDayModel DayModel
     {
@@ -27,11 +30,16 @@ public partial class DayColumnControl : Control
         set { SetValue(DayModelProperty, value); }
     }
 
-    public static readonly DependencyProperty DayModelProperty = DependencyProperty.Register(nameof(DayModel), typeof(CalendarDayModel), typeof(DayColumnControl), new PropertyMetadata(null, new PropertyChangedCallback(OnRenderingPropertiesChanged)));
+    public static readonly DependencyProperty DayModelProperty = DependencyProperty.Register(
+        nameof(DayModel),
+        typeof(CalendarDayModel),
+        typeof(DayColumnControl),
+        new PropertyMetadata(null, new PropertyChangedCallback(OnRenderingPropertiesChanged)));
 
     public DayColumnControl()
     {
         DefaultStyleKey = typeof(DayColumnControl);
+        Unloaded += OnUnloaded;
     }
 
     protected override void OnApplyTemplate()
@@ -43,6 +51,7 @@ public partial class DayColumnControl : Control
         IsTodayBorder = GetTemplateChild(PART_IsTodayBorder) as Border;
         AllDayItemsControl = GetTemplateChild(PART_AllDayItemsControl) as ItemsControl;
 
+        RegisterEventsCollectionHandlers();
         UpdateValues();
     }
 
@@ -50,15 +59,78 @@ public partial class DayColumnControl : Control
     {
         if (control is DayColumnControl columnControl)
         {
+            columnControl.RegisterEventsCollectionHandlers();
             columnControl.UpdateValues();
         }
     }
 
+    private void OnUnloaded(object sender, RoutedEventArgs e)
+    {
+        DeregisterEventsCollectionHandlers();
+    }
+
+    private bool IsMonthlyTemplate() => ColumnHeaderText == null;
+
+    private void RegisterEventsCollectionHandlers()
+    {
+        var nextCollection = DayModel?.EventsCollection;
+        if (ReferenceEquals(_boundEventsCollection, nextCollection))
+            return;
+
+        DeregisterEventsCollectionHandlers();
+
+        _boundEventsCollection = nextCollection;
+        if (_boundEventsCollection == null)
+            return;
+
+        ((INotifyCollectionChanged)_boundEventsCollection.AllDayEvents).CollectionChanged += EventsCollectionChanged;
+        ((INotifyCollectionChanged)_boundEventsCollection.RegularEvents).CollectionChanged += EventsCollectionChanged;
+    }
+
+    private void DeregisterEventsCollectionHandlers()
+    {
+        if (_boundEventsCollection == null)
+            return;
+
+        ((INotifyCollectionChanged)_boundEventsCollection.AllDayEvents).CollectionChanged -= EventsCollectionChanged;
+        ((INotifyCollectionChanged)_boundEventsCollection.RegularEvents).CollectionChanged -= EventsCollectionChanged;
+        _boundEventsCollection = null;
+    }
+
+    private void EventsCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
+    {
+        UpdateEventItemsSource();
+    }
+
+    private void UpdateEventItemsSource()
+    {
+        if (AllDayItemsControl == null || DayModel == null) return;
+
+        if (IsMonthlyTemplate())
+        {
+            // Month cells should show all events for the day, not only all-day/multi-day.
+            var monthlyItems = DayModel.EventsCollection.AllDayEvents
+                .Concat(DayModel.EventsCollection.RegularEvents)
+                .GroupBy(a => a.Id)
+                .Select(g => g.First())
+                .OrderBy(a => a.StartDate)
+                .ToList();
+
+            AllDayItemsControl.ItemsSource = monthlyItems;
+            return;
+        }
+
+        AllDayItemsControl.ItemsSource = DayModel.EventsCollection.AllDayEvents;
+    }
+
     private void UpdateValues()
     {
-        if (HeaderDateDayText == null || IsTodayBorder == null || DayModel == null) return;
+        if (DayModel == null) return;
 
-        HeaderDateDayText.Text = DayModel.RepresentingDate.Day.ToString();
+        if (HeaderDateDayText != null)
+        {
+            HeaderDateDayText.Text = DayModel.RepresentingDate.Day.ToString();
+        }
 
         // Monthly template does not use it.
         if (ColumnHeaderText != null)
@@ -66,8 +138,9 @@ public partial class DayColumnControl : Control
             ColumnHeaderText.Text = DayModel.RepresentingDate.ToString("dddd", DayModel.CalendarRenderOptions.CalendarSettings.CultureInfo);
         }
 
-        AllDayItemsControl.ItemsSource = DayModel.EventsCollection.AllDayEvents;
+        UpdateEventItemsSource();
 
+        if (IsTodayBorder == null) return;
         bool isToday = DayModel.RepresentingDate.Date == DateTime.Now.Date;
 
         VisualStateManager.GoToState(this, isToday ? TodayState : NotTodayState, false);

Wino.Calendar/Controls/WinoCalendarControl.cs

@@ -34,7 +34,7 @@ public partial class WinoCalendarControl : Control
     public static readonly DependencyProperty VerticalItemsPanelTemplateProperty = DependencyProperty.Register(nameof(VerticalItemsPanelTemplate), typeof(ItemsPanelTemplate), typeof(WinoCalendarControl), new PropertyMetadata(null, new PropertyChangedCallback(OnCalendarOrientationPropertiesUpdated)));
     public static readonly DependencyProperty HorizontalItemsPanelTemplateProperty = DependencyProperty.Register(nameof(HorizontalItemsPanelTemplate), typeof(ItemsPanelTemplate), typeof(WinoCalendarControl), new PropertyMetadata(null, new PropertyChangedCallback(OnCalendarOrientationPropertiesUpdated)));
     public static readonly DependencyProperty OrientationProperty = DependencyProperty.Register(nameof(Orientation), typeof(CalendarOrientation), typeof(WinoCalendarControl), new PropertyMetadata(CalendarOrientation.Horizontal, new PropertyChangedCallback(OnCalendarOrientationPropertiesUpdated)));
-    public static readonly DependencyProperty DisplayTypeProperty = DependencyProperty.Register(nameof(DisplayType), typeof(CalendarDisplayType), typeof(WinoCalendarControl), new PropertyMetadata(CalendarDisplayType.Day));
+    public static readonly DependencyProperty DisplayTypeProperty = DependencyProperty.Register(nameof(DisplayType), typeof(CalendarDisplayType), typeof(WinoCalendarControl), new PropertyMetadata(CalendarDisplayType.Day, new PropertyChangedCallback(OnDisplayTypeChanged)));
 
     /// <summary>
     /// Gets or sets the day-week-month-year display type.
@@ -171,6 +171,14 @@ public partial class WinoCalendarControl : Control
         }
     }
 
+    private static void OnDisplayTypeChanged(DependencyObject calendar, DependencyPropertyChangedEventArgs e)
+    {
+        if (calendar is WinoCalendarControl calendarControl)
+        {
+            calendarControl.ManageDisplayType();
+        }
+    }
+
     private void ManageCalendarOrientation()
     {
         if (InternalFlipView == null || HorizontalItemsPanelTemplate == null || VerticalItemsPanelTemplate == null) return;
@@ -178,6 +186,13 @@ public partial class WinoCalendarControl : Control
         InternalFlipView.ItemsPanel = Orientation == CalendarOrientation.Horizontal ? HorizontalItemsPanelTemplate : VerticalItemsPanelTemplate;
     }
 
+    private void ManageDisplayType()
+    {
+        if (InternalFlipView == null) return;
+
+        InternalFlipView.DisplayType = DisplayType;
+    }
+
     private void ManageHighlightedDateRange()
         => SelectedFlipViewDayRange = InternalFlipView.SelectedItem as DayRangeRenderModel;
 
@@ -232,6 +247,7 @@ public partial class WinoCalendarControl : Control
 
         UpdateIdleState();
         ManageCalendarOrientation();
+        ManageDisplayType();
     }
 
     private void UpdateIdleState()

Wino.Calendar/Controls/WinoCalendarTypeSelectorControl.cs

@@ -12,9 +12,12 @@ public partial class WinoCalendarTypeSelectorControl : Control
     private const string PART_DayToggle = nameof(PART_DayToggle);
     private const string PART_WeekToggle = nameof(PART_WeekToggle);
     private const string PART_MonthToggle = nameof(PART_MonthToggle);
-    private const string PART_YearToggle = nameof(PART_YearToggle);
 
-    public static readonly DependencyProperty SelectedTypeProperty = DependencyProperty.Register(nameof(SelectedType), typeof(CalendarDisplayType), typeof(WinoCalendarTypeSelectorControl), new PropertyMetadata(CalendarDisplayType.Week));
+    public static readonly DependencyProperty SelectedTypeProperty = DependencyProperty.Register(
+        nameof(SelectedType),
+        typeof(CalendarDisplayType),
+        typeof(WinoCalendarTypeSelectorControl),
+        new PropertyMetadata(CalendarDisplayType.Week, new PropertyChangedCallback(OnSelectedTypeChanged)));
     public static readonly DependencyProperty DisplayDayCountProperty = DependencyProperty.Register(nameof(DisplayDayCount), typeof(int), typeof(WinoCalendarTypeSelectorControl), new PropertyMetadata(0));
     public static readonly DependencyProperty TodayClickedCommandProperty = DependencyProperty.Register(nameof(TodayClickedCommand), typeof(ICommand), typeof(WinoCalendarTypeSelectorControl), new PropertyMetadata(null));
 
@@ -40,7 +43,6 @@ public partial class WinoCalendarTypeSelectorControl : Control
     private AppBarToggleButton _dayToggle;
     private AppBarToggleButton _weekToggle;
     private AppBarToggleButton _monthToggle;
-    private AppBarToggleButton _yearToggle;
 
     public WinoCalendarTypeSelectorControl()
     {
@@ -51,24 +53,23 @@ public partial class WinoCalendarTypeSelectorControl : Control
     {
         base.OnApplyTemplate();
 
+        UnregisterHandlers();
+
         _todayButton = GetTemplateChild(PART_TodayButton) as AppBarButton;
         _dayToggle = GetTemplateChild(PART_DayToggle) as AppBarToggleButton;
         _weekToggle = GetTemplateChild(PART_WeekToggle) as AppBarToggleButton;
         _monthToggle = GetTemplateChild(PART_MonthToggle) as AppBarToggleButton;
-        _yearToggle = GetTemplateChild(PART_YearToggle) as AppBarToggleButton;
 
         Guard.IsNotNull(_todayButton, nameof(_todayButton));
         Guard.IsNotNull(_dayToggle, nameof(_dayToggle));
         Guard.IsNotNull(_weekToggle, nameof(_weekToggle));
         Guard.IsNotNull(_monthToggle, nameof(_monthToggle));
-        Guard.IsNotNull(_yearToggle, nameof(_yearToggle));
 
         _todayButton.Click += TodayClicked;
 
         _dayToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Day); };
         _weekToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Week); };
         _monthToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Month); };
-        _yearToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Year); };
 
         UpdateToggleButtonStates();
     }
@@ -81,11 +82,26 @@ public partial class WinoCalendarTypeSelectorControl : Control
         UpdateToggleButtonStates();
     }
 
+    private static void OnSelectedTypeChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+    {
+        var control = d as WinoCalendarTypeSelectorControl;
+        control?.UpdateToggleButtonStates();
+    }
+
+    private void UnregisterHandlers()
+    {
+        if (_todayButton != null)
+        {
+            _todayButton.Click -= TodayClicked;
+        }
+    }
+
     private void UpdateToggleButtonStates()
     {
+        if (_dayToggle == null || _weekToggle == null || _monthToggle == null) return;
+
         _dayToggle.IsChecked = SelectedType == CalendarDisplayType.Day;
         _weekToggle.IsChecked = SelectedType == CalendarDisplayType.Week;
         _monthToggle.IsChecked = SelectedType == CalendarDisplayType.Month;
-        _yearToggle.IsChecked = SelectedType == CalendarDisplayType.Year;
     }
 }

Wino.Calendar/Selectors/WinoCalendarItemTemplateSelector.cs

@@ -22,8 +22,6 @@ public partial class WinoCalendarItemTemplateSelector : DataTemplateSelector
                 return DayWeekWorkWeekTemplate;
             case CalendarDisplayType.Month:
                 return MonthlyTemplate;
-            case CalendarDisplayType.Year:
-                break;
             default:
                 break;
         }

Wino.Calendar/Styles/WinoCalendarResources.xaml

@@ -367,6 +367,9 @@
                     <RowDefinition Height="*" MinHeight="35" />
                 </Grid.RowDefinitions>
 
+                <!--  Day number  -->
+                <TextBlock x:Name="PART_HeaderDateDayText" FontSize="17" />
+
                 <!--  Extras  -->
                 <StackPanel Grid.Column="1" HorizontalAlignment="Right" />
 

Wino.Calendar/Styles/WinoCalendarTypeSelectorControl.xaml

@@ -61,16 +61,6 @@
                                     </AppBarToggleButton.Icon>
                                 </AppBarToggleButton>
 
-                                <!--  Year  -->
-                                <AppBarToggleButton
-                                    x:Name="PART_YearToggle"
-                                    Foreground="{ThemeResource ApplicationForegroundThemeBrush}"
-                                    Label="Year">
-                                    <AppBarToggleButton.Icon>
-                                        <controls1:WinoFontIcon Icon="CalendarYear" />
-                                    </AppBarToggleButton.Icon>
-                                </AppBarToggleButton>
-
                             </CommandBar.PrimaryCommands>
                         </CommandBar>
                     </ControlTemplate>

Wino.Calendar/Views/AppShell.xaml

@@ -1,4 +1,4 @@
-<abstract:AppShellAbstract
+<abstract:AppShellAbstract
     x:Class="Wino.Calendar.Views.AppShell"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
@@ -119,6 +119,7 @@
                                 FontSize="14"
                                 FontWeight="Normal"
                                 IsHitTestVisible="False"
+                                DisplayType="{x:Bind ViewModel.StatePersistenceService.CalendarDisplayType, Mode=OneWay}"
                                 ItemsSource="{x:Bind ViewModel.DateNavigationHeaderItems}"
                                 SelectedIndex="{x:Bind ViewModel.SelectedDateNavigationHeaderIndex, Mode=OneWay}">
                                 <FlipView.ItemTemplate>

Wino.Calendar/Views/AppShell.xaml.cs

@@ -20,13 +20,13 @@ public sealed partial class AppShell : AppShellAbstract,
         InitializeComponent();
 
         Window.Current.SetTitleBar(DragArea);
-        ManageCalendarDisplayType();
+        ManageCalendarDisplayType(ViewModel.StatePersistenceService.CalendarDisplayType);
     }
 
-    private void ManageCalendarDisplayType()
+    private void ManageCalendarDisplayType(Core.Domain.Enums.CalendarDisplayType displayType)
     {
         // Go to different states based on the display type.
-        if (ViewModel.IsVerticalCalendar)
+        if (displayType == Core.Domain.Enums.CalendarDisplayType.Month)
         {
             VisualStateManager.GoToState(this, STATE_VerticalCalendar, false);
         }
@@ -42,7 +42,7 @@ public sealed partial class AppShell : AppShellAbstract,
 
     public void Receive(CalendarDisplayTypeChangedMessage message)
     {
-        ManageCalendarDisplayType();
+        ManageCalendarDisplayType(message.NewDisplayType);
     }
 
     private void ShellFrameContentNavigated(object sender, Windows.UI.Xaml.Navigation.NavigationEventArgs e)

Wino.Core.Domain/Enums/CalendarDisplayType.cs

@@ -5,6 +5,5 @@ public enum CalendarDisplayType
     Day,
     Week,
     WorkWeek,
-    Month,
+    Month
-    Year
 }

Wino.Mail.WinUI/Controls/Calendar/CustomCalendarFlipView.cs

@@ -1,7 +1,8 @@
-using System.Linq;
+using System.Linq;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Automation.Peers;
 using Microsoft.UI.Xaml.Controls;
+using Wino.Core.Domain.Enums;
 using Wino.Mail.WinUI.Controls.CalendarFlipView;
 
 namespace Wino.Calendar.Controls;
@@ -11,27 +12,56 @@ namespace Wino.Calendar.Controls;
 /// </summary>
 public partial class CustomCalendarFlipView : FlipView
 {
-    private const string PART_PreviousButton = "PreviousButtonHorizontal";
+    private const string PART_PreviousButtonHorizontal = "PreviousButtonHorizontal";
-    private const string PART_NextButton = "NextButtonHorizontal";
+    private const string PART_NextButtonHorizontal = "NextButtonHorizontal";
+    private const string PART_PreviousButtonVertical = "PreviousButtonVertical";
+    private const string PART_NextButtonVertical = "NextButtonVertical";
 
-    private Button? PreviousButton;
+    public static readonly DependencyProperty DisplayTypeProperty = DependencyProperty.Register(
-    private Button? NextButton;
+        nameof(DisplayType),
+        typeof(CalendarDisplayType),
+        typeof(CustomCalendarFlipView),
+        new PropertyMetadata(CalendarDisplayType.Week));
+
+    public CalendarDisplayType DisplayType
+    {
+        get => (CalendarDisplayType)GetValue(DisplayTypeProperty);
+        set => SetValue(DisplayTypeProperty, value);
+    }
+
+    private Button? PreviousButtonHorizontal;
+    private Button? NextButtonHorizontal;
+    private Button? PreviousButtonVertical;
+    private Button? NextButtonVertical;
 
     protected override void OnApplyTemplate()
     {
         base.OnApplyTemplate();
 
-        PreviousButton = (Button)GetTemplateChild(PART_PreviousButton);
+        PreviousButtonHorizontal = GetTemplateChild(PART_PreviousButtonHorizontal) as Button;
-        NextButton = (Button)GetTemplateChild(PART_NextButton);
+        NextButtonHorizontal = GetTemplateChild(PART_NextButtonHorizontal) as Button;
+        PreviousButtonVertical = GetTemplateChild(PART_PreviousButtonVertical) as Button;
+        NextButtonVertical = GetTemplateChild(PART_NextButtonVertical) as Button;
 
         // Hide navigation buttons
-        PreviousButton.Opacity = NextButton.Opacity = 0;
+        HideButton(PreviousButtonHorizontal);
-        PreviousButton.IsHitTestVisible = NextButton.IsHitTestVisible = false;
+        HideButton(NextButtonHorizontal);
+        HideButton(PreviousButtonVertical);
+        HideButton(NextButtonVertical);
 
-        this.SelectionChanged += FlipViewSelectionChanged;
+        SelectionChanged += FlipViewSelectionChanged;
     }
 
-    private void FlipViewSelectionChanged(object sender, SelectionChangedEventArgs e) => OnSelectedItemChanged(e.RemovedItems.FirstOrDefault(), e.AddedItems.FirstOrDefault());
+    private static void HideButton(Button? button)
+    {
+        if (button == null) return;
+
+        button.Opacity = 0;
+        button.IsHitTestVisible = false;
+    }
+
+    private void FlipViewSelectionChanged(object sender, SelectionChangedEventArgs e)
+        => OnSelectedItemChanged(e.RemovedItems.FirstOrDefault(), e.AddedItems.FirstOrDefault());
 
     protected virtual void OnSelectedItemChanged(object oldValue, object newValue) { }
 
@@ -47,13 +77,25 @@ public partial class CustomCalendarFlipView : FlipView
 
     public void GoPreviousFlip()
     {
-        var backPeer = new ButtonAutomationPeer(PreviousButton);
+        var previousButton = DisplayType == CalendarDisplayType.Month
+            ? PreviousButtonVertical ?? PreviousButtonHorizontal
+            : PreviousButtonHorizontal ?? PreviousButtonVertical;
+
+        if (previousButton == null) return;
+
+        var backPeer = new ButtonAutomationPeer(previousButton);
         backPeer.Invoke();
     }
 
     public void GoNextFlip()
     {
-        var nextPeer = new ButtonAutomationPeer(NextButton);
+        var nextButton = DisplayType == CalendarDisplayType.Month
+            ? NextButtonVertical ?? NextButtonHorizontal
+            : NextButtonHorizontal ?? NextButtonVertical;
+
+        if (nextButton == null) return;
+
+        var nextPeer = new ButtonAutomationPeer(nextButton);
         nextPeer.Invoke();
     }
 }

Wino.Mail.WinUI/Controls/Calendar/DayColumnControl.cs

@@ -1,6 +1,9 @@
-using System;
+using System;
+using System.Collections.Specialized;
+using System.Linq;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
+using Wino.Core.Domain.Collections;
 using Wino.Core.Domain.Models.Calendar;
 
 namespace Wino.Calendar.Controls;
@@ -10,7 +13,6 @@ public partial class DayColumnControl : Control
     private const string PART_HeaderDateDayText = nameof(PART_HeaderDateDayText);
     private const string PART_IsTodayBorder = nameof(PART_IsTodayBorder);
     private const string PART_ColumnHeaderText = nameof(PART_ColumnHeaderText);
-
     private const string PART_AllDayItemsControl = nameof(PART_AllDayItemsControl);
 
     private const string TodayState = nameof(TodayState);
@@ -20,6 +22,7 @@ public partial class DayColumnControl : Control
     private TextBlock ColumnHeaderText;
     private Border IsTodayBorder;
     private ItemsControl AllDayItemsControl;
+    private CalendarEventCollection _boundEventsCollection;
 
     public CalendarDayModel DayModel
     {
@@ -27,11 +30,16 @@ public partial class DayColumnControl : Control
         set { SetValue(DayModelProperty, value); }
     }
 
-    public static readonly DependencyProperty DayModelProperty = DependencyProperty.Register(nameof(DayModel), typeof(CalendarDayModel), typeof(DayColumnControl), new PropertyMetadata(null, new PropertyChangedCallback(OnRenderingPropertiesChanged)));
+    public static readonly DependencyProperty DayModelProperty = DependencyProperty.Register(
+        nameof(DayModel),
+        typeof(CalendarDayModel),
+        typeof(DayColumnControl),
+        new PropertyMetadata(null, new PropertyChangedCallback(OnRenderingPropertiesChanged)));
 
     public DayColumnControl()
     {
         DefaultStyleKey = typeof(DayColumnControl);
+        Unloaded += OnUnloaded;
     }
 
     protected override void OnApplyTemplate()
@@ -43,6 +51,7 @@ public partial class DayColumnControl : Control
         IsTodayBorder = GetTemplateChild(PART_IsTodayBorder) as Border;
         AllDayItemsControl = GetTemplateChild(PART_AllDayItemsControl) as ItemsControl;
 
+        RegisterEventsCollectionHandlers();
         UpdateValues();
     }
 
@@ -50,15 +59,78 @@ public partial class DayColumnControl : Control
     {
         if (control is DayColumnControl columnControl)
         {
+            columnControl.RegisterEventsCollectionHandlers();
             columnControl.UpdateValues();
         }
     }
 
+    private void OnUnloaded(object sender, RoutedEventArgs e)
+    {
+        DeregisterEventsCollectionHandlers();
+    }
+
+    private bool IsMonthlyTemplate() => ColumnHeaderText == null;
+
+    private void RegisterEventsCollectionHandlers()
+    {
+        var nextCollection = DayModel?.EventsCollection;
+        if (ReferenceEquals(_boundEventsCollection, nextCollection))
+            return;
+
+        DeregisterEventsCollectionHandlers();
+
+        _boundEventsCollection = nextCollection;
+        if (_boundEventsCollection == null)
+            return;
+
+        ((INotifyCollectionChanged)_boundEventsCollection.AllDayEvents).CollectionChanged += EventsCollectionChanged;
+        ((INotifyCollectionChanged)_boundEventsCollection.RegularEvents).CollectionChanged += EventsCollectionChanged;
+    }
+
+    private void DeregisterEventsCollectionHandlers()
+    {
+        if (_boundEventsCollection == null)
+            return;
+
+        ((INotifyCollectionChanged)_boundEventsCollection.AllDayEvents).CollectionChanged -= EventsCollectionChanged;
+        ((INotifyCollectionChanged)_boundEventsCollection.RegularEvents).CollectionChanged -= EventsCollectionChanged;
+        _boundEventsCollection = null;
+    }
+
+    private void EventsCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
+    {
+        UpdateEventItemsSource();
+    }
+
+    private void UpdateEventItemsSource()
+    {
+        if (AllDayItemsControl == null || DayModel == null) return;
+
+        if (IsMonthlyTemplate())
+        {
+            // Month cells should show all events for the day, not only all-day/multi-day.
+            var monthlyItems = DayModel.EventsCollection.AllDayEvents
+                .Concat(DayModel.EventsCollection.RegularEvents)
+                .GroupBy(a => a.Id)
+                .Select(g => g.First())
+                .OrderBy(a => a.StartDate)
+                .ToList();
+
+            AllDayItemsControl.ItemsSource = monthlyItems;
+            return;
+        }
+
+        AllDayItemsControl.ItemsSource = DayModel.EventsCollection.AllDayEvents;
+    }
+
     private void UpdateValues()
     {
-        if (HeaderDateDayText == null || IsTodayBorder == null || DayModel == null) return;
+        if (DayModel == null) return;
 
-        HeaderDateDayText.Text = DayModel.RepresentingDate.Day.ToString();
+        if (HeaderDateDayText != null)
+        {
+            HeaderDateDayText.Text = DayModel.RepresentingDate.Day.ToString();
+        }
 
         // Monthly template does not use it.
         if (ColumnHeaderText != null)
@@ -66,8 +138,9 @@ public partial class DayColumnControl : Control
             ColumnHeaderText.Text = DayModel.RepresentingDate.ToString("dddd", DayModel.CalendarRenderOptions.CalendarSettings.CultureInfo);
         }
 
-        AllDayItemsControl.ItemsSource = DayModel.EventsCollection.AllDayEvents;
+        UpdateEventItemsSource();
 
+        if (IsTodayBorder == null) return;
         bool isToday = DayModel.RepresentingDate.Date == DateTime.Now.Date;
 
         VisualStateManager.GoToState(this, isToday ? TodayState : NotTodayState, false);

Wino.Mail.WinUI/Controls/Calendar/WinoCalendarControl.cs

@@ -87,6 +87,9 @@ public partial class WinoCalendarControl : Control
     partial void OnOrientationChanged(CalendarOrientation newValue)
         => ManageCalendarOrientation();
 
+    partial void OnDisplayTypeChanged(CalendarDisplayType newValue)
+        => ManageDisplayType();
+
     partial void OnIsFlipIdleChanged(bool newValue)
         => UpdateIdleState();
 
@@ -131,6 +134,13 @@ public partial class WinoCalendarControl : Control
         InternalFlipView.ItemsPanel = Orientation == CalendarOrientation.Horizontal ? HorizontalItemsPanelTemplate : VerticalItemsPanelTemplate;
     }
 
+    private void ManageDisplayType()
+    {
+        if (InternalFlipView == null) return;
+
+        InternalFlipView.DisplayType = DisplayType;
+    }
+
     private void ManageHighlightedDateRange()
         => SelectedFlipViewDayRange = InternalFlipView.SelectedItem as DayRangeRenderModel;
 
@@ -185,6 +195,7 @@ public partial class WinoCalendarControl : Control
 
         UpdateIdleState();
         ManageCalendarOrientation();
+        ManageDisplayType();
     }
 
     private void UpdateIdleState()

Wino.Mail.WinUI/Controls/Calendar/WinoCalendarTypeSelectorControl.cs

@@ -12,9 +12,12 @@ public partial class WinoCalendarTypeSelectorControl : Control
     private const string PART_DayToggle = nameof(PART_DayToggle);
     private const string PART_WeekToggle = nameof(PART_WeekToggle);
     private const string PART_MonthToggle = nameof(PART_MonthToggle);
-    private const string PART_YearToggle = nameof(PART_YearToggle);
 
-    public static readonly DependencyProperty SelectedTypeProperty = DependencyProperty.Register(nameof(SelectedType), typeof(CalendarDisplayType), typeof(WinoCalendarTypeSelectorControl), new PropertyMetadata(CalendarDisplayType.Week));
+    public static readonly DependencyProperty SelectedTypeProperty = DependencyProperty.Register(
+        nameof(SelectedType),
+        typeof(CalendarDisplayType),
+        typeof(WinoCalendarTypeSelectorControl),
+        new PropertyMetadata(CalendarDisplayType.Week, OnSelectedTypeChanged));
     public static readonly DependencyProperty DisplayDayCountProperty = DependencyProperty.Register(nameof(DisplayDayCount), typeof(int), typeof(WinoCalendarTypeSelectorControl), new PropertyMetadata(0));
     public static readonly DependencyProperty TodayClickedCommandProperty = DependencyProperty.Register(nameof(TodayClickedCommand), typeof(ICommand), typeof(WinoCalendarTypeSelectorControl), new PropertyMetadata(null));
 
@@ -40,7 +43,6 @@ public partial class WinoCalendarTypeSelectorControl : Control
     private AppBarToggleButton _dayToggle;
     private AppBarToggleButton _weekToggle;
     private AppBarToggleButton _monthToggle;
-    private AppBarToggleButton _yearToggle;
 
     public WinoCalendarTypeSelectorControl()
     {
@@ -51,24 +53,23 @@ public partial class WinoCalendarTypeSelectorControl : Control
     {
         base.OnApplyTemplate();
 
+        UnregisterHandlers();
+
         _todayButton = GetTemplateChild(PART_TodayButton) as AppBarButton;
         _dayToggle = GetTemplateChild(PART_DayToggle) as AppBarToggleButton;
         _weekToggle = GetTemplateChild(PART_WeekToggle) as AppBarToggleButton;
         _monthToggle = GetTemplateChild(PART_MonthToggle) as AppBarToggleButton;
-        _yearToggle = GetTemplateChild(PART_YearToggle) as AppBarToggleButton;
 
         Guard.IsNotNull(_todayButton, nameof(_todayButton));
         Guard.IsNotNull(_dayToggle, nameof(_dayToggle));
         Guard.IsNotNull(_weekToggle, nameof(_weekToggle));
         Guard.IsNotNull(_monthToggle, nameof(_monthToggle));
-        Guard.IsNotNull(_yearToggle, nameof(_yearToggle));
 
         _todayButton.Click += TodayClicked;
 
         _dayToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Day); };
         _weekToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Week); };
         _monthToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Month); };
-        _yearToggle.Click += (s, e) => { SetSelectedType(CalendarDisplayType.Year); };
 
         UpdateToggleButtonStates();
     }
@@ -81,11 +82,29 @@ public partial class WinoCalendarTypeSelectorControl : Control
         UpdateToggleButtonStates();
     }
 
+    private static void OnSelectedTypeChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+    {
+        var control = d as WinoCalendarTypeSelectorControl;
+        control?.UpdateToggleButtonStates();
+    }
+
+    private void UnregisterHandlers()
+    {
+        if (_todayButton != null)
+        {
+            _todayButton.Click -= TodayClicked;
+        }
+    }
+
     private void UpdateToggleButtonStates()
     {
+        if (_dayToggle == null || _weekToggle == null || _monthToggle == null)
+        {
+            return;
+        }
+
         _dayToggle.IsChecked = SelectedType == CalendarDisplayType.Day;
         _weekToggle.IsChecked = SelectedType == CalendarDisplayType.Week;
         _monthToggle.IsChecked = SelectedType == CalendarDisplayType.Month;
-        _yearToggle.IsChecked = SelectedType == CalendarDisplayType.Year;
     }
 }

Wino.Mail.WinUI/Selectors/WinoCalendarItemTemplateSelector.cs

@@ -22,8 +22,6 @@ public partial class WinoCalendarItemTemplateSelector : DataTemplateSelector
                 return DayWeekWorkWeekTemplate;
             case CalendarDisplayType.Month:
                 return MonthlyTemplate;
-            case CalendarDisplayType.Year:
-                break;
             default:
                 break;
         }

Wino.Mail.WinUI/Services/StatePersistenceService.cs

@@ -22,7 +22,7 @@ public class StatePersistenceService : ObservableObject, IStatePersistanceServic
 
         _openPaneLength = _configurationService.Get(OpenPaneLengthKey, 320d);
         _mailListPaneLength = _configurationService.Get(MailListPaneLengthKey, 420d);
-        _calendarDisplayType = _configurationService.Get(nameof(CalendarDisplayType), CalendarDisplayType.Week);
+        _calendarDisplayType = EnsureValidCalendarDisplayType(_configurationService.Get(nameof(CalendarDisplayType), CalendarDisplayType.Week));
         _dayDisplayCount = _configurationService.Get(nameof(DayDisplayCount), 1);
 
         PropertyChanged += ServicePropertyChanged;
@@ -176,9 +176,11 @@ public class StatePersistenceService : ObservableObject, IStatePersistanceServic
         get => _calendarDisplayType;
         set
         {
-            if (SetProperty(ref _calendarDisplayType, value))
+            var validValue = EnsureValidCalendarDisplayType(value);
+
+            if (SetProperty(ref _calendarDisplayType, validValue))
             {
-                _configurationService.Set(nameof(CalendarDisplayType), value);
+                _configurationService.Set(nameof(CalendarDisplayType), validValue);
             }
         }
     }
@@ -197,4 +199,11 @@ public class StatePersistenceService : ObservableObject, IStatePersistanceServic
     }
 
     private void UpdateAppCoreWindowTitle() => WinoApplication.MainWindow.Title = CoreWindowTitle;
+
+    private static CalendarDisplayType EnsureValidCalendarDisplayType(CalendarDisplayType displayType)
+    {
+        return Enum.IsDefined(typeof(CalendarDisplayType), displayType)
+            ? displayType
+            : CalendarDisplayType.Week;
+    }
 }

Wino.Mail.WinUI/Styles/WinoCalendarResources.xaml

@@ -390,6 +390,9 @@
                     <RowDefinition Height="*" MinHeight="35" />
                 </Grid.RowDefinitions>
 
+                <!--  Day number  -->
+                <TextBlock x:Name="PART_HeaderDateDayText" FontSize="17" />
+
                 <!--  Extras  -->
                 <StackPanel Grid.Column="1" HorizontalAlignment="Right" />
 

Wino.Mail.WinUI/Styles/WinoCalendarTypeSelectorControl.xaml

@@ -61,16 +61,6 @@
                                     </AppBarToggleButton.Icon>
                                 </AppBarToggleButton>
 
-                                <!--  Year  -->
-                                <AppBarToggleButton
-                                    x:Name="PART_YearToggle"
-                                    Foreground="{ThemeResource ApplicationForegroundThemeBrush}"
-                                    Label="Year">
-                                    <AppBarToggleButton.Icon>
-                                        <controls1:WinoFontIcon Icon="CalendarYear" />
-                                    </AppBarToggleButton.Icon>
-                                </AppBarToggleButton>
-
                             </CommandBar.PrimaryCommands>
                         </CommandBar>
                     </ControlTemplate>

Wino.Mail.WinUI/Views/Calendar/CalendarAppShell.xaml

@@ -1,4 +1,4 @@
-<abstract:CalendarAppShellAbstract
+<abstract:CalendarAppShellAbstract
     x:Class="Wino.Mail.WinUI.Views.Calendar.CalendarAppShell"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
@@ -85,6 +85,7 @@
                         FontSize="14"
                         FontWeight="Normal"
                         IsHitTestVisible="False"
+                        DisplayType="{x:Bind ViewModel.StatePersistenceService.CalendarDisplayType, Mode=OneWay}"
                         ItemsSource="{x:Bind ViewModel.DateNavigationHeaderItems}"
                         SelectedIndex="{x:Bind ViewModel.SelectedDateNavigationHeaderIndex, Mode=OneWay}">
                         <FlipView.ItemTemplate>

Wino.Mail.WinUI/Views/Calendar/CalendarAppShell.xaml.cs

@@ -19,13 +19,13 @@ public sealed partial class CalendarAppShell : CalendarAppShellAbstract,
         InitializeComponent();
 
         // Window.Current.SetTitleBar(DragArea);
-        ManageCalendarDisplayType();
+        ManageCalendarDisplayType(ViewModel.StatePersistenceService.CalendarDisplayType);
     }
 
-    private void ManageCalendarDisplayType()
+    private void ManageCalendarDisplayType(Core.Domain.Enums.CalendarDisplayType displayType)
     {
         // Go to different states based on the display type.
-        if (ViewModel.IsVerticalCalendar)
+        if (displayType == Core.Domain.Enums.CalendarDisplayType.Month)
         {
             VisualStateManager.GoToState(this, STATE_VerticalCalendar, false);
         }
@@ -41,7 +41,7 @@ public sealed partial class CalendarAppShell : CalendarAppShellAbstract,
 
     public void Receive(CalendarDisplayTypeChangedMessage message)
     {
-        ManageCalendarDisplayType();
+        ManageCalendarDisplayType(message.NewDisplayType);
     }
 
     //private void ShellFrameContentNavigated(object sender, Microsoft.UI.Xaml.Navigation.NavigationEventArgs e)