From 9926d1d0c27a879586abde6520d7cfaca7f262be Mon Sep 17 00:00:00 2001
From: Erik Darling <2136037+erikdarlingdata@users.noreply.github.com>
Date: Wed, 18 Feb 2026 15:18:00 -0500
Subject: [PATCH 1/3] Add loading overlay and contextual empty states (#106, PR
 1)

Reusable LoadingOverlay control with spinning animation and randomized
loading messages. Wired into DailySummary, Memory, and QueryPerformance
tabs. Extracted shared LoadingMessages helper from ServerTab, added
EmptyStateMessage style for context-specific empty states. Lite gets
the LoadingMessages helper (UI wiring in PR 2).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 Dashboard/Controls/DailySummaryContent.xaml   |  5 +-
 .../Controls/DailySummaryContent.xaml.cs      |  7 +++
 Dashboard/Controls/LoadingOverlay.xaml        | 48 +++++++++++++++++++
 Dashboard/Controls/LoadingOverlay.xaml.cs     | 41 ++++++++++++++++
 Dashboard/Controls/MemoryContent.xaml         |  9 +++-
 Dashboard/Controls/MemoryContent.xaml.cs      | 14 ++++++
 .../Controls/QueryPerformanceContent.xaml     |  8 +++-
 .../Controls/QueryPerformanceContent.xaml.cs  | 14 ++++++
 Dashboard/Helpers/LoadingMessages.cs          | 46 ++++++++++++++++++
 Dashboard/ServerTab.xaml.cs                   | 31 +-----------
 Dashboard/Themes/DarkTheme.xaml               |  9 ++++
 Lite/Helpers/LoadingMessages.cs               | 43 +++++++++++++++++
 12 files changed, 240 insertions(+), 35 deletions(-)
 create mode 100644 Dashboard/Controls/LoadingOverlay.xaml
 create mode 100644 Dashboard/Controls/LoadingOverlay.xaml.cs
 create mode 100644 Dashboard/Helpers/LoadingMessages.cs
 create mode 100644 Lite/Helpers/LoadingMessages.cs

diff --git a/Dashboard/Controls/DailySummaryContent.xaml b/Dashboard/Controls/DailySummaryContent.xaml
index e6d2ab0c..652a8b8f 100644
--- a/Dashboard/Controls/DailySummaryContent.xaml
+++ b/Dashboard/Controls/DailySummaryContent.xaml
@@ -3,6 +3,7 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             xmlns:controls="clr-namespace:PerformanceMonitorDashboard.Controls"
              mc:Ignorable="d"
              d:DesignHeight="450" d:DesignWidth="800">
     <UserControl.Resources>
@@ -144,7 +145,9 @@
                 </DataGridTextColumn>
             </DataGrid.Columns>
         </DataGrid>
-        <TextBlock x:Name="DailySummaryNoDataMessage" Style="{StaticResource NoDataMessage}"/>
+        <TextBlock x:Name="DailySummaryNoDataMessage" Style="{StaticResource EmptyStateMessage}"
+                   Text="No daily summary data. Try selecting a different date."/>
+        <controls:LoadingOverlay x:Name="DailySummaryLoading"/>
         </Grid>
     </Grid>
 </UserControl>
diff --git a/Dashboard/Controls/DailySummaryContent.xaml.cs b/Dashboard/Controls/DailySummaryContent.xaml.cs
index 802c1a47..eda60644 100644
--- a/Dashboard/Controls/DailySummaryContent.xaml.cs
+++ b/Dashboard/Controls/DailySummaryContent.xaml.cs
@@ -79,6 +79,9 @@ private async System.Threading.Tasks.Task LoadDailySummaryAsync()
 
             try
             {
+                DailySummaryLoading.IsLoading = true;
+                DailySummaryNoDataMessage.Visibility = Visibility.Collapsed;
+
                 var data = await _databaseService.GetDailySummaryAsync(_dailySummaryDate);
 
                 // Store unfiltered data and reset filters when new data is loaded
@@ -100,6 +103,10 @@ private async System.Threading.Tasks.Task LoadDailySummaryAsync()
             {
                 Logger.Error($"Error loading daily summary: {ex.Message}");
             }
+            finally
+            {
+                DailySummaryLoading.IsLoading = false;
+            }
         }
 
         #region Event Handlers
diff --git a/Dashboard/Controls/LoadingOverlay.xaml b/Dashboard/Controls/LoadingOverlay.xaml
new file mode 100644
index 00000000..4fbbeaa6
--- /dev/null
+++ b/Dashboard/Controls/LoadingOverlay.xaml
@@ -0,0 +1,48 @@
+<UserControl x:Class="PerformanceMonitorDashboard.Controls.LoadingOverlay"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             mc:Ignorable="d"
+             Visibility="Collapsed"
+             d:DesignHeight="200" d:DesignWidth="400">
+    <UserControl.Resources>
+        <ResourceDictionary>
+            <ResourceDictionary.MergedDictionaries>
+                <ResourceDictionary Source="/Themes/DarkTheme.xaml"/>
+            </ResourceDictionary.MergedDictionaries>
+        </ResourceDictionary>
+    </UserControl.Resources>
+    <Grid Background="{DynamicResource BackgroundBrush}">
+        <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
+            <TextBlock x:Name="SpinnerText"
+                       Text="&#x27F3;"
+                       FontSize="24"
+                       Foreground="{DynamicResource AccentBrush}"
+                       HorizontalAlignment="Center"
+                       RenderTransformOrigin="0.5,0.5">
+                <TextBlock.RenderTransform>
+                    <RotateTransform x:Name="SpinnerRotation"/>
+                </TextBlock.RenderTransform>
+                <TextBlock.Triggers>
+                    <EventTrigger RoutedEvent="Loaded">
+                        <BeginStoryboard>
+                            <Storyboard RepeatBehavior="Forever">
+                                <DoubleAnimation
+                                    Storyboard.TargetName="SpinnerRotation"
+                                    Storyboard.TargetProperty="Angle"
+                                    From="0" To="360"
+                                    Duration="0:0:1"/>
+                            </Storyboard>
+                        </BeginStoryboard>
+                    </EventTrigger>
+                </TextBlock.Triggers>
+            </TextBlock>
+            <TextBlock x:Name="MessageText"
+                       FontSize="14"
+                       Foreground="{DynamicResource ForegroundMutedBrush}"
+                       HorizontalAlignment="Center"
+                       Margin="0,8,0,0"/>
+        </StackPanel>
+    </Grid>
+</UserControl>
diff --git a/Dashboard/Controls/LoadingOverlay.xaml.cs b/Dashboard/Controls/LoadingOverlay.xaml.cs
new file mode 100644
index 00000000..b9b6810f
--- /dev/null
+++ b/Dashboard/Controls/LoadingOverlay.xaml.cs
@@ -0,0 +1,41 @@
+using System.Windows;
+using System.Windows.Controls;
+using PerformanceMonitorDashboard.Helpers;
+
+namespace PerformanceMonitorDashboard.Controls
+{
+    public partial class LoadingOverlay : UserControl
+    {
+        public static readonly DependencyProperty IsLoadingProperty =
+            DependencyProperty.Register(
+                nameof(IsLoading),
+                typeof(bool),
+                typeof(LoadingOverlay),
+                new PropertyMetadata(false, OnIsLoadingChanged));
+
+        public bool IsLoading
+        {
+            get => (bool)GetValue(IsLoadingProperty);
+            set => SetValue(IsLoadingProperty, value);
+        }
+
+        public LoadingOverlay()
+        {
+            InitializeComponent();
+        }
+
+        private static void OnIsLoadingChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            if (d is LoadingOverlay overlay)
+            {
+                var isLoading = (bool)e.NewValue;
+                overlay.Visibility = isLoading ? Visibility.Visible : Visibility.Collapsed;
+
+                if (isLoading)
+                {
+                    overlay.MessageText.Text = LoadingMessages.GetRandom();
+                }
+            }
+        }
+    }
+}
diff --git a/Dashboard/Controls/MemoryContent.xaml b/Dashboard/Controls/MemoryContent.xaml
index 298686c1..bae6cf3b 100644
--- a/Dashboard/Controls/MemoryContent.xaml
+++ b/Dashboard/Controls/MemoryContent.xaml
@@ -4,6 +4,7 @@
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
              xmlns:ScottPlot="clr-namespace:ScottPlot.WPF;assembly=ScottPlot.WPF"
+             xmlns:controls="clr-namespace:PerformanceMonitorDashboard.Controls"
              mc:Ignorable="d"
              d:DesignHeight="600" d:DesignWidth="1200">
     <UserControl.Resources>
@@ -90,7 +91,9 @@
                             <TextBlock x:Name="MemoryGrantsForcedText" Text="0" Foreground="{DynamicResource ForegroundBrush}" VerticalAlignment="Center"/>
                         </StackPanel>
                     </Border>
-                    <TextBlock x:Name="MemoryGrantsNoDataMessage" Grid.Row="1" Style="{StaticResource NoDataMessage}"/>
+                    <TextBlock x:Name="MemoryGrantsNoDataMessage" Grid.Row="1" Style="{StaticResource EmptyStateMessage}"
+                               Text="No memory grant data in selected time range"/>
+                    <controls:LoadingOverlay x:Name="MemoryGrantsLoading" Grid.Row="1"/>
                 </Grid>
             </Border>
         </TabItem>
@@ -116,7 +119,9 @@
                             <TextBlock x:Name="MemoryClerksTopText" Text="N/A" Foreground="{DynamicResource ForegroundBrush}" VerticalAlignment="Center"/>
                         </StackPanel>
                     </Border>
-                    <TextBlock x:Name="MemoryClerksNoDataMessage" Grid.Row="1" Style="{StaticResource NoDataMessage}"/>
+                    <TextBlock x:Name="MemoryClerksNoDataMessage" Grid.Row="1" Style="{StaticResource EmptyStateMessage}"
+                               Text="No memory clerk data in selected time range"/>
+                    <controls:LoadingOverlay x:Name="MemoryClerksLoading" Grid.Row="1"/>
                 </Grid>
             </Border>
         </TabItem>
diff --git a/Dashboard/Controls/MemoryContent.xaml.cs b/Dashboard/Controls/MemoryContent.xaml.cs
index b9c7c9e6..f2b35d6f 100644
--- a/Dashboard/Controls/MemoryContent.xaml.cs
+++ b/Dashboard/Controls/MemoryContent.xaml.cs
@@ -383,6 +383,9 @@ private async System.Threading.Tasks.Task RefreshMemoryGrantsAsync()
 
             try
             {
+                MemoryGrantsLoading.IsLoading = true;
+                MemoryGrantsNoDataMessage.Visibility = Visibility.Collapsed;
+
                 var data = await _databaseService.GetMemoryGrantStatsAsync(_memoryGrantsHoursBack, _memoryGrantsFromDate, _memoryGrantsToDate);
                 var dataList = data.ToList();
                 MemoryGrantsNoDataMessage.Visibility = dataList.Count == 0 ? Visibility.Visible : Visibility.Collapsed;
@@ -392,6 +395,10 @@ private async System.Threading.Tasks.Task RefreshMemoryGrantsAsync()
             {
                 Logger.Error($"Error loading memory grants: {ex.Message}");
             }
+            finally
+            {
+                MemoryGrantsLoading.IsLoading = false;
+            }
         }
 
         private void LoadMemoryGrantsChart(IEnumerable<MemoryGrantStatsItem> data, int hoursBack, DateTime? fromDate, DateTime? toDate)
@@ -485,6 +492,9 @@ private async System.Threading.Tasks.Task RefreshMemoryClerksAsync()
 
             try
             {
+                MemoryClerksLoading.IsLoading = true;
+                MemoryClerksNoDataMessage.Visibility = Visibility.Collapsed;
+
                 var data = await _databaseService.GetMemoryClerksTopNAsync(5, _memoryClerksHoursBack, _memoryClerksFromDate, _memoryClerksToDate);
                 var dataList = data.ToList();
                 MemoryClerksNoDataMessage.Visibility = dataList.Count == 0 ? Visibility.Visible : Visibility.Collapsed;
@@ -494,6 +504,10 @@ private async System.Threading.Tasks.Task RefreshMemoryClerksAsync()
             {
                 Logger.Error($"Error loading memory clerks: {ex.Message}");
             }
+            finally
+            {
+                MemoryClerksLoading.IsLoading = false;
+            }
         }
 
         private void LoadMemoryClerksChart(List<MemoryClerksItem> data, int hoursBack, DateTime? fromDate, DateTime? toDate)
diff --git a/Dashboard/Controls/QueryPerformanceContent.xaml b/Dashboard/Controls/QueryPerformanceContent.xaml
index 12bf9709..ca8c9dd3 100644
--- a/Dashboard/Controls/QueryPerformanceContent.xaml
+++ b/Dashboard/Controls/QueryPerformanceContent.xaml
@@ -314,7 +314,9 @@
                     </DataGridTemplateColumn>
                 </DataGrid.Columns>
             </DataGrid>
-            <TextBlock x:Name="ActiveQueriesNoDataMessage" Style="{StaticResource NoDataMessage}"/>
+            <TextBlock x:Name="ActiveQueriesNoDataMessage" Style="{StaticResource EmptyStateMessage}"
+                       Text="No active queries found"/>
+            <local:LoadingOverlay x:Name="ActiveQueriesLoading"/>
             </Grid>
         </TabItem>
 
@@ -585,7 +587,9 @@
                     </DataGridTextColumn>
                 </DataGrid.Columns>
             </DataGrid>
-            <TextBlock x:Name="QueryStatsNoDataMessage" Style="{StaticResource NoDataMessage}"/>
+            <TextBlock x:Name="QueryStatsNoDataMessage" Style="{StaticResource EmptyStateMessage}"
+                       Text="No query statistics in selected time range"/>
+            <local:LoadingOverlay x:Name="QueryStatsLoading"/>
             </Grid>
         </TabItem>
 
diff --git a/Dashboard/Controls/QueryPerformanceContent.xaml.cs b/Dashboard/Controls/QueryPerformanceContent.xaml.cs
index e903040d..b93a0805 100644
--- a/Dashboard/Controls/QueryPerformanceContent.xaml.cs
+++ b/Dashboard/Controls/QueryPerformanceContent.xaml.cs
@@ -217,6 +217,9 @@ public async Task RefreshAllDataAsync()
 
                 if (_databaseService == null) return;
 
+                QueryStatsLoading.IsLoading = true;
+                QueryStatsNoDataMessage.Visibility = Visibility.Collapsed;
+
                 // Fetch grid data (summary views aggregated per query/procedure)
                 var queryStatsTask = _databaseService.GetQueryStatsAsync(_queryStatsHoursBack, _queryStatsFromDate, _queryStatsToDate);
                 var procStatsTask = _databaseService.GetProcedureStatsAsync(_procStatsHoursBack, _procStatsFromDate, _procStatsToDate);
@@ -263,6 +266,10 @@ await Task.WhenAll(
             {
                 Logger.Error($"Error refreshing QueryPerformance data: {ex.Message}", ex);
             }
+            finally
+            {
+                QueryStatsLoading.IsLoading = false;
+            }
         }
 
         private void SetStatus(string message)
@@ -367,7 +374,10 @@ private async Task RefreshActiveQueriesAsync()
 
             try
             {
+                ActiveQueriesLoading.IsLoading = true;
+                ActiveQueriesNoDataMessage.Visibility = Visibility.Collapsed;
                 SetStatus("Loading active queries...");
+
                 var data = await _databaseService.GetQuerySnapshotsAsync(_activeQueriesHoursBack, _activeQueriesFromDate, _activeQueriesToDate);
                 ActiveQueriesDataGrid.ItemsSource = data;
                 ActiveQueriesNoDataMessage.Visibility = data.Count == 0 ? Visibility.Visible : Visibility.Collapsed;
@@ -378,6 +388,10 @@ private async Task RefreshActiveQueriesAsync()
                 Logger.Error($"Error loading active queries: {ex.Message}");
                 SetStatus("Error loading active queries");
             }
+            finally
+            {
+                ActiveQueriesLoading.IsLoading = false;
+            }
         }
 
         private void ActiveQueriesFilter_Click(object sender, RoutedEventArgs e)
diff --git a/Dashboard/Helpers/LoadingMessages.cs b/Dashboard/Helpers/LoadingMessages.cs
new file mode 100644
index 00000000..0f4f9102
--- /dev/null
+++ b/Dashboard/Helpers/LoadingMessages.cs
@@ -0,0 +1,46 @@
+using System;
+
+namespace PerformanceMonitorDashboard.Helpers
+{
+    /// <summary>
+    /// Randomized loading messages displayed while data is being fetched.
+    /// </summary>
+    public static class LoadingMessages
+    {
+        private static readonly string[] Messages =
+        [
+            "Reticulating splines...",
+            "Consulting the oracle...",
+            "Asking the database nicely...",
+            "Crunching numbers...",
+            "Thinking really hard...",
+            "Mulling it over...",
+            "Communing with SQL Server...",
+            "Summoning data spirits...",
+            "Decoding the matrix...",
+            "Interrogating indexes...",
+            "Parsing the void...",
+            "Calibrating flux capacitors...",
+            "Negotiating with stored procedures...",
+            "Convincing queries to run faster...",
+            "Herding cursors...",
+            "Massaging execution plans...",
+            "Whispering to wait stats...",
+            "Befriending buffer pools...",
+            "Coaxing data from disk...",
+            "Pondering performance...",
+            "Untangling spaghetti queries...",
+            "Poking the query optimizer...",
+            "Warming up the plan cache...",
+            "Dusting off statistics...",
+            "Reasoning with RESOURCE_SEMAPHORE...",
+            "Apologizing to tempdb...",
+            "Flattering the cardinality estimator...",
+            "Bribing the lock manager...",
+            "Decrypting wait stats hieroglyphics...",
+            "Teaching cursors to fly...",
+        ];
+
+        public static string GetRandom() => Messages[Random.Shared.Next(Messages.Length)];
+    }
+}
diff --git a/Dashboard/ServerTab.xaml.cs b/Dashboard/ServerTab.xaml.cs
index 51c17f69..b1d47686 100644
--- a/Dashboard/ServerTab.xaml.cs
+++ b/Dashboard/ServerTab.xaml.cs
@@ -35,36 +35,7 @@ public partial class ServerTab : UserControl
         public int UtcOffsetMinutes { get; }
 
         public DatabaseService DatabaseService => _databaseService;
-        // Fun AI-powered loading messages
-        private static readonly string[] _loadingMessages = new[]
-        {
-            "Reticulating splines...",
-            "Consulting the oracle...",
-            "Asking the database nicely...",
-            "Crunching numbers...",
-            "Thinking really hard...",
-            "Mulling it over...",
-            "Communing with SQL Server...",
-            "Summoning data spirits...",
-            "Decoding the matrix...",
-            "Interrogating indexes...",
-            "Parsing the void...",
-            "Calibrating flux capacitors...",
-            "Negotiating with stored procedures...",
-            "Convincing queries to run faster...",
-            "Herding cursors...",
-            "Massaging execution plans...",
-            "Whispering to wait stats...",
-            "Befriending buffer pools...",
-            "Coaxing data from disk...",
-            "Pondering performance..."
-        };
-        private static readonly Random _loadingRandom = Random.Shared;
-
-        private string GetLoadingMessage()
-        {
-            return _loadingMessages[_loadingRandom.Next(_loadingMessages.Length)];
-        }
+        private static string GetLoadingMessage() => LoadingMessages.GetRandom();
 
 
         private readonly UserPreferencesService _preferencesService;
diff --git a/Dashboard/Themes/DarkTheme.xaml b/Dashboard/Themes/DarkTheme.xaml
index 686dcef6..7390435c 100644
--- a/Dashboard/Themes/DarkTheme.xaml
+++ b/Dashboard/Themes/DarkTheme.xaml
@@ -157,6 +157,15 @@
         <Setter Property="Visibility" Value="Collapsed"/>
     </Style>
 
+    <!-- Empty State Message Style (context-specific text set per usage) -->
+    <Style x:Key="EmptyStateMessage" TargetType="TextBlock">
+        <Setter Property="Foreground" Value="{StaticResource ForegroundMutedBrush}"/>
+        <Setter Property="FontSize" Value="14"/>
+        <Setter Property="HorizontalAlignment" Value="Center"/>
+        <Setter Property="VerticalAlignment" Value="Center"/>
+        <Setter Property="Visibility" Value="Collapsed"/>
+    </Style>
+
     <!-- Alert Badge Styles -->
     <Style x:Key="AlertBadge" TargetType="Border">
         <Setter Property="Background" Value="#D97706"/>
diff --git a/Lite/Helpers/LoadingMessages.cs b/Lite/Helpers/LoadingMessages.cs
new file mode 100644
index 00000000..628fef2a
--- /dev/null
+++ b/Lite/Helpers/LoadingMessages.cs
@@ -0,0 +1,43 @@
+namespace PerformanceMonitorLite.Helpers;
+
+/// <summary>
+/// Randomized loading messages displayed while data is being fetched.
+/// </summary>
+public static class LoadingMessages
+{
+    private static readonly string[] Messages =
+    [
+        "Reticulating splines...",
+        "Consulting the oracle...",
+        "Asking the database nicely...",
+        "Crunching numbers...",
+        "Thinking really hard...",
+        "Mulling it over...",
+        "Communing with SQL Server...",
+        "Summoning data spirits...",
+        "Decoding the matrix...",
+        "Interrogating indexes...",
+        "Parsing the void...",
+        "Calibrating flux capacitors...",
+        "Negotiating with stored procedures...",
+        "Convincing queries to run faster...",
+        "Herding cursors...",
+        "Massaging execution plans...",
+        "Whispering to wait stats...",
+        "Befriending buffer pools...",
+        "Coaxing data from disk...",
+        "Pondering performance...",
+        "Untangling spaghetti queries...",
+        "Poking the query optimizer...",
+        "Warming up the plan cache...",
+        "Dusting off statistics...",
+        "Reasoning with RESOURCE_SEMAPHORE...",
+        "Apologizing to tempdb...",
+        "Flattering the cardinality estimator...",
+        "Bribing the lock manager...",
+        "Decrypting wait stats hieroglyphics...",
+        "Teaching cursors to fly...",
+    ];
+
+    public static string GetRandom() => Messages[Random.Shared.Next(Messages.Length)];
+}

From 39787f28820c788e76da04b1240c9d8b13c57f83 Mon Sep 17 00:00:00 2001
From: Erik Darling <2136037+erikdarlingdata@users.noreply.github.com>
Date: Wed, 18 Feb 2026 15:58:53 -0500
Subject: [PATCH 2/3] Fix loading overlay showing on every auto-refresh

Only show the loading overlay on initial load when no data exists yet.
Subsequent auto-refreshes keep existing data visible while fetching.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 Dashboard/Controls/DailySummaryContent.xaml.cs   |  8 ++++++--
 Dashboard/Controls/MemoryContent.xaml.cs         | 16 ++++++++++++----
 .../Controls/QueryPerformanceContent.xaml.cs     | 16 ++++++++++++----
 3 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/Dashboard/Controls/DailySummaryContent.xaml.cs b/Dashboard/Controls/DailySummaryContent.xaml.cs
index eda60644..e7d77b5b 100644
--- a/Dashboard/Controls/DailySummaryContent.xaml.cs
+++ b/Dashboard/Controls/DailySummaryContent.xaml.cs
@@ -79,8 +79,12 @@ private async System.Threading.Tasks.Task LoadDailySummaryAsync()
 
             try
             {
-                DailySummaryLoading.IsLoading = true;
-                DailySummaryNoDataMessage.Visibility = Visibility.Collapsed;
+                // Only show loading overlay on initial load (no existing data)
+                if (DailySummaryDataGrid.ItemsSource == null)
+                {
+                    DailySummaryLoading.IsLoading = true;
+                    DailySummaryNoDataMessage.Visibility = Visibility.Collapsed;
+                }
 
                 var data = await _databaseService.GetDailySummaryAsync(_dailySummaryDate);
 
diff --git a/Dashboard/Controls/MemoryContent.xaml.cs b/Dashboard/Controls/MemoryContent.xaml.cs
index f2b35d6f..90399ecb 100644
--- a/Dashboard/Controls/MemoryContent.xaml.cs
+++ b/Dashboard/Controls/MemoryContent.xaml.cs
@@ -383,8 +383,12 @@ private async System.Threading.Tasks.Task RefreshMemoryGrantsAsync()
 
             try
             {
-                MemoryGrantsLoading.IsLoading = true;
-                MemoryGrantsNoDataMessage.Visibility = Visibility.Collapsed;
+                // Only show loading overlay on initial load (no existing chart data)
+                if (!MemoryGrantsChart.Plot.GetPlottables().Any())
+                {
+                    MemoryGrantsLoading.IsLoading = true;
+                    MemoryGrantsNoDataMessage.Visibility = Visibility.Collapsed;
+                }
 
                 var data = await _databaseService.GetMemoryGrantStatsAsync(_memoryGrantsHoursBack, _memoryGrantsFromDate, _memoryGrantsToDate);
                 var dataList = data.ToList();
@@ -492,8 +496,12 @@ private async System.Threading.Tasks.Task RefreshMemoryClerksAsync()
 
             try
             {
-                MemoryClerksLoading.IsLoading = true;
-                MemoryClerksNoDataMessage.Visibility = Visibility.Collapsed;
+                // Only show loading overlay on initial load (no existing chart data)
+                if (!MemoryClerksChart.Plot.GetPlottables().Any())
+                {
+                    MemoryClerksLoading.IsLoading = true;
+                    MemoryClerksNoDataMessage.Visibility = Visibility.Collapsed;
+                }
 
                 var data = await _databaseService.GetMemoryClerksTopNAsync(5, _memoryClerksHoursBack, _memoryClerksFromDate, _memoryClerksToDate);
                 var dataList = data.ToList();
diff --git a/Dashboard/Controls/QueryPerformanceContent.xaml.cs b/Dashboard/Controls/QueryPerformanceContent.xaml.cs
index b93a0805..cf0ce161 100644
--- a/Dashboard/Controls/QueryPerformanceContent.xaml.cs
+++ b/Dashboard/Controls/QueryPerformanceContent.xaml.cs
@@ -217,8 +217,12 @@ public async Task RefreshAllDataAsync()
 
                 if (_databaseService == null) return;
 
-                QueryStatsLoading.IsLoading = true;
-                QueryStatsNoDataMessage.Visibility = Visibility.Collapsed;
+                // Only show loading overlay on initial load (no existing data)
+                if (QueryStatsDataGrid.ItemsSource == null)
+                {
+                    QueryStatsLoading.IsLoading = true;
+                    QueryStatsNoDataMessage.Visibility = Visibility.Collapsed;
+                }
 
                 // Fetch grid data (summary views aggregated per query/procedure)
                 var queryStatsTask = _databaseService.GetQueryStatsAsync(_queryStatsHoursBack, _queryStatsFromDate, _queryStatsToDate);
@@ -374,8 +378,12 @@ private async Task RefreshActiveQueriesAsync()
 
             try
             {
-                ActiveQueriesLoading.IsLoading = true;
-                ActiveQueriesNoDataMessage.Visibility = Visibility.Collapsed;
+                // Only show loading overlay on initial load (no existing data)
+                if (ActiveQueriesDataGrid.ItemsSource == null)
+                {
+                    ActiveQueriesLoading.IsLoading = true;
+                    ActiveQueriesNoDataMessage.Visibility = Visibility.Collapsed;
+                }
                 SetStatus("Loading active queries...");
 
                 var data = await _databaseService.GetQuerySnapshotsAsync(_activeQueriesHoursBack, _activeQueriesFromDate, _activeQueriesToDate);

From 33178f53c0f37cafd7062664ea251a866ec91dc7 Mon Sep 17 00:00:00 2001
From: Erik Darling <2136037+erikdarlingdata@users.noreply.github.com>
Date: Wed, 18 Feb 2026 17:22:48 -0500
Subject: [PATCH 3/3] Add CriticalIssues overlay, Lite LoadingOverlay control,
 fix dark tooltip

- Wire LoadingOverlay into CriticalIssuesContent with initial-load-only pattern
- Add LoadingOverlay UserControl to Lite (not wired to grids yet)
- Fix Lite alert badge tooltip to use dark theme instead of default Windows light theme (#120)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 Dashboard/Controls/CriticalIssuesContent.xaml |  4 +-
 .../Controls/CriticalIssuesContent.xaml.cs    | 11 +++++
 Lite/Controls/LoadingOverlay.xaml             | 48 +++++++++++++++++++
 Lite/Controls/LoadingOverlay.xaml.cs          | 40 ++++++++++++++++
 Lite/MainWindow.xaml.cs                       |  8 +++-
 5 files changed, 109 insertions(+), 2 deletions(-)
 create mode 100644 Lite/Controls/LoadingOverlay.xaml
 create mode 100644 Lite/Controls/LoadingOverlay.xaml.cs

diff --git a/Dashboard/Controls/CriticalIssuesContent.xaml b/Dashboard/Controls/CriticalIssuesContent.xaml
index 545f9cf4..17ce8acb 100644
--- a/Dashboard/Controls/CriticalIssuesContent.xaml
+++ b/Dashboard/Controls/CriticalIssuesContent.xaml
@@ -3,6 +3,7 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             xmlns:controls="clr-namespace:PerformanceMonitorDashboard.Controls"
              mc:Ignorable="d"
              d:DesignHeight="450" d:DesignWidth="800">
     <UserControl.Resources>
@@ -107,6 +108,7 @@
             </DataGridTextColumn>
         </DataGrid.Columns>
     </DataGrid>
-    <TextBlock x:Name="CriticalIssuesNoDataMessage" Style="{StaticResource NoDataMessage}"/>
+    <TextBlock x:Name="CriticalIssuesNoDataMessage" Style="{StaticResource EmptyStateMessage}" Text="No critical issues detected in selected time range"/>
+    <controls:LoadingOverlay x:Name="CriticalIssuesLoading"/>
     </Grid>
 </UserControl>
diff --git a/Dashboard/Controls/CriticalIssuesContent.xaml.cs b/Dashboard/Controls/CriticalIssuesContent.xaml.cs
index 93ded66c..cecc99c2 100644
--- a/Dashboard/Controls/CriticalIssuesContent.xaml.cs
+++ b/Dashboard/Controls/CriticalIssuesContent.xaml.cs
@@ -93,6 +93,13 @@ private async System.Threading.Tasks.Task LoadCriticalIssuesAsync()
 
             try
             {
+                // Only show loading overlay on initial load (no existing data)
+                if (CriticalIssuesDataGrid.ItemsSource == null)
+                {
+                    CriticalIssuesLoading.IsLoading = true;
+                    CriticalIssuesNoDataMessage.Visibility = Visibility.Collapsed;
+                }
+
                 var data = await _databaseService.GetCriticalIssuesAsync(
                     _criticalIssuesHoursBack,
                     _criticalIssuesFromDate,
@@ -111,6 +118,10 @@ private async System.Threading.Tasks.Task LoadCriticalIssuesAsync()
             {
                 Logger.Error($"Error loading critical issues: {ex.Message}");
             }
+            finally
+            {
+                CriticalIssuesLoading.IsLoading = false;
+            }
         }
 
         #region Filter Popup Handlers
diff --git a/Lite/Controls/LoadingOverlay.xaml b/Lite/Controls/LoadingOverlay.xaml
new file mode 100644
index 00000000..86a900e2
--- /dev/null
+++ b/Lite/Controls/LoadingOverlay.xaml
@@ -0,0 +1,48 @@
+<UserControl x:Class="PerformanceMonitorLite.Controls.LoadingOverlay"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             mc:Ignorable="d"
+             Visibility="Collapsed"
+             d:DesignHeight="200" d:DesignWidth="400">
+    <UserControl.Resources>
+        <ResourceDictionary>
+            <ResourceDictionary.MergedDictionaries>
+                <ResourceDictionary Source="/Themes/DarkTheme.xaml"/>
+            </ResourceDictionary.MergedDictionaries>
+        </ResourceDictionary>
+    </UserControl.Resources>
+    <Grid Background="{DynamicResource BackgroundBrush}">
+        <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
+            <TextBlock x:Name="SpinnerText"
+                       Text="&#x27F3;"
+                       FontSize="24"
+                       Foreground="{DynamicResource AccentBrush}"
+                       HorizontalAlignment="Center"
+                       RenderTransformOrigin="0.5,0.5">
+                <TextBlock.RenderTransform>
+                    <RotateTransform x:Name="SpinnerRotation"/>
+                </TextBlock.RenderTransform>
+                <TextBlock.Triggers>
+                    <EventTrigger RoutedEvent="Loaded">
+                        <BeginStoryboard>
+                            <Storyboard RepeatBehavior="Forever">
+                                <DoubleAnimation
+                                    Storyboard.TargetName="SpinnerRotation"
+                                    Storyboard.TargetProperty="Angle"
+                                    From="0" To="360"
+                                    Duration="0:0:1"/>
+                            </Storyboard>
+                        </BeginStoryboard>
+                    </EventTrigger>
+                </TextBlock.Triggers>
+            </TextBlock>
+            <TextBlock x:Name="MessageText"
+                       FontSize="14"
+                       Foreground="{DynamicResource ForegroundMutedBrush}"
+                       HorizontalAlignment="Center"
+                       Margin="0,8,0,0"/>
+        </StackPanel>
+    </Grid>
+</UserControl>
diff --git a/Lite/Controls/LoadingOverlay.xaml.cs b/Lite/Controls/LoadingOverlay.xaml.cs
new file mode 100644
index 00000000..4fd9f5a3
--- /dev/null
+++ b/Lite/Controls/LoadingOverlay.xaml.cs
@@ -0,0 +1,40 @@
+using System.Windows;
+using System.Windows.Controls;
+using PerformanceMonitorLite.Helpers;
+
+namespace PerformanceMonitorLite.Controls;
+
+public partial class LoadingOverlay : UserControl
+{
+    public static readonly DependencyProperty IsLoadingProperty =
+        DependencyProperty.Register(
+            nameof(IsLoading),
+            typeof(bool),
+            typeof(LoadingOverlay),
+            new PropertyMetadata(false, OnIsLoadingChanged));
+
+    public bool IsLoading
+    {
+        get => (bool)GetValue(IsLoadingProperty);
+        set => SetValue(IsLoadingProperty, value);
+    }
+
+    public LoadingOverlay()
+    {
+        InitializeComponent();
+    }
+
+    private static void OnIsLoadingChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+    {
+        if (d is LoadingOverlay overlay)
+        {
+            var isLoading = (bool)e.NewValue;
+            overlay.Visibility = isLoading ? Visibility.Visible : Visibility.Collapsed;
+
+            if (isLoading)
+            {
+                overlay.MessageText.Text = LoadingMessages.GetRandom();
+            }
+        }
+    }
+}
diff --git a/Lite/MainWindow.xaml.cs b/Lite/MainWindow.xaml.cs
index a29d0600..30c0d6ac 100644
--- a/Lite/MainWindow.xaml.cs
+++ b/Lite/MainWindow.xaml.cs
@@ -649,7 +649,13 @@ not when the user just switches time ranges. */
                     if (border.Child is TextBlock text)
                     {
                         text.Text = totalAlerts > 99 ? "99+" : totalAlerts.ToString();
-                        text.ToolTip = $"Blocking: {blockingCount}, Deadlocks: {deadlockCount}\nRight-click to dismiss";
+                        text.ToolTip = new System.Windows.Controls.ToolTip
+                        {
+                            Content = $"Blocking: {blockingCount}, Deadlocks: {deadlockCount}\nRight-click to dismiss",
+                            Background = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(0x1E, 0x1E, 0x2E)),
+                            Foreground = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(0xE4, 0xE6, 0xEB)),
+                            BorderBrush = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(0x3A, 0x3D, 0x45))
+                        };
                     }
                 }
                 else