From 7b6794b711d8fac15780835eaa1e55b6d80e906a Mon Sep 17 00:00:00 2001
From: Darren Batchelor <v-dbatchelor@microsoft.com>
Date: Tue, 7 Dec 2021 15:20:25 -0800
Subject: [PATCH 1/7] Init commit

---
 .../Triggers/IsNullOrEmptyStateTrigger.cs     |  4 +-
 .../Test_IsNullOrEmptyStateTrigger.cs         | 41 +++++++++++++++++++
 UnitTests/UnitTests.UWP/UnitTests.UWP.csproj  |  1 +
 3 files changed, 45 insertions(+), 1 deletion(-)
 create mode 100644 UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs

diff --git a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
index 7eec265e229..f5692a72879 100644
--- a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
+++ b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
@@ -30,12 +30,14 @@ public object Value
         public static readonly DependencyProperty ValueProperty =
             DependencyProperty.Register(nameof(Value), typeof(object), typeof(IsNullOrEmptyStateTrigger), new PropertyMetadata(true, OnValuePropertyChanged));
 
+        public static bool IsActive { get; private set; }
+
         private static void OnValuePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
         {
             var obj = (IsNullOrEmptyStateTrigger)d;
             var val = e.NewValue;
 
-            obj.SetActive(IsNullOrEmpty(val));
+            obj.SetActive(IsActive = IsNullOrEmpty(val));
 
             if (val == null)
             {
diff --git a/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs b/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs
new file mode 100644
index 00000000000..bcfae42570c
--- /dev/null
+++ b/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs
@@ -0,0 +1,41 @@
+using Microsoft.Toolkit.Uwp;
+using Microsoft.Toolkit.Uwp.UI.Triggers;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Windows.UI.Xaml;
+using Windows.UI.Xaml.Controls;
+using Windows.UI.Xaml.Data;
+
+namespace UnitTests.UWP.UI.Triggers
+{
+    [TestClass]
+    [TestCategory("Test_IsNullOrEmptyStateTrigger")]
+    public class Test_IsNullOrEmptyStateTrigger : VisualUITestBase
+    {
+        [TestMethod]
+        public async Task IsNullOrEmptyStateTrigger_SelectedItem()
+        {
+            await App.DispatcherQueue.EnqueueAsync(async () =>
+            {
+                //Grid grid = CreateGrid(width, height);
+                var listView = new ListView { Name="myListView"};
+                await SetTestContentAsync(listView);
+                
+                var trigger = new IsNullOrEmptyStateTrigger();
+                Binding nullOrEmptyStateBinding = new Binding();
+                nullOrEmptyStateBinding.Source = this; // listView;
+                nullOrEmptyStateBinding.Path = new PropertyPath("SelectedItem");
+                nullOrEmptyStateBinding.Mode = BindingMode.OneWay;
+                BindingOperations.SetBinding(listView, ListView.SelectedItemProperty, nullOrEmptyStateBinding);
+
+                var bol = IsNullOrEmptyStateTrigger.IsActive;
+
+                Assert.AreEqual(true, bol);
+            });
+        }
+    }
+}
diff --git a/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj b/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj
index cdbb101c62a..0d5bafa2ad3 100644
--- a/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj
+++ b/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj
@@ -259,6 +259,7 @@
     <Compile Include="UI\Person.cs" />
     <Compile Include="UI\Test_AdvancedCollectionView.cs" />
     <Compile Include="UI\Triggers\Test_ControlSizeTrigger.cs" />
+    <Compile Include="UI\Triggers\Test_IsNullOrEmptyStateTrigger.cs" />
     <Compile Include="VisualUITestBase.cs" />
   </ItemGroup>
   <ItemGroup>

From fac2b1b91fecefaf6b97cd46fdc760ef64f5d0d0 Mon Sep 17 00:00:00 2001
From: Darren Batchelor <v-dbatchelor@microsoft.com>
Date: Fri, 10 Dec 2021 14:45:25 -0800
Subject: [PATCH 2/7] Change default value from true to null

---
 .../Triggers/IsNullOrEmptyStateTrigger.bind           |  1 +
 .../Triggers/IsNullOrEmptyStateTrigger.cs             |  5 ++++-
 .../UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs     | 11 +++++------
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
index 51ccd36ebef..c4c757366fc 100644
--- a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
+++ b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
@@ -26,6 +26,7 @@
         <VisualState x:Name="ListEmptyState">
           <VisualState.StateTriggers>
             <triggers:IsNullOrEmptyStateTrigger Value="{Binding Items, ElementName=OurList, Mode=OneWay}"/>
+          <!--<triggers:IsNullOrEmptyStateTrigger Value="{Binding SelectedItem, ElementName=OurList, Mode=OneWay}"/>-->
           </VisualState.StateTriggers>
           <VisualState.Setters>
             <Setter Target="RemoveButton.IsEnabled" Value="False" />
diff --git a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
index f5692a72879..a22b06f09bd 100644
--- a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
+++ b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
@@ -28,8 +28,11 @@ public object Value
         /// Identifies the <see cref="Value"/> DependencyProperty
         /// </summary>
         public static readonly DependencyProperty ValueProperty =
-            DependencyProperty.Register(nameof(Value), typeof(object), typeof(IsNullOrEmptyStateTrigger), new PropertyMetadata(true, OnValuePropertyChanged));
+            DependencyProperty.Register(nameof(Value), typeof(object), typeof(IsNullOrEmptyStateTrigger), new PropertyMetadata(null, OnValuePropertyChanged));
 
+        /// <summary>
+        /// Gets a value indicating whether the trigger is active.
+        /// </summary>
         public static bool IsActive { get; private set; }
 
         private static void OnValuePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
diff --git a/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs b/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs
index bcfae42570c..9dac624ea3e 100644
--- a/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs
+++ b/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs
@@ -1,10 +1,10 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
 using Microsoft.Toolkit.Uwp;
 using Microsoft.Toolkit.Uwp.UI.Triggers;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Windows.UI.Xaml;
 using Windows.UI.Xaml.Controls;
@@ -21,13 +21,12 @@ public async Task IsNullOrEmptyStateTrigger_SelectedItem()
         {
             await App.DispatcherQueue.EnqueueAsync(async () =>
             {
-                //Grid grid = CreateGrid(width, height);
                 var listView = new ListView { Name="myListView"};
                 await SetTestContentAsync(listView);
                 
                 var trigger = new IsNullOrEmptyStateTrigger();
                 Binding nullOrEmptyStateBinding = new Binding();
-                nullOrEmptyStateBinding.Source = this; // listView;
+                nullOrEmptyStateBinding.Source = this;
                 nullOrEmptyStateBinding.Path = new PropertyPath("SelectedItem");
                 nullOrEmptyStateBinding.Mode = BindingMode.OneWay;
                 BindingOperations.SetBinding(listView, ListView.SelectedItemProperty, nullOrEmptyStateBinding);

From 0a7677c9165bdf667e36dadeb263ca5f6b25c3c2 Mon Sep 17 00:00:00 2001
From: Darren Batchelor <v-dbatchelor@microsoft.com>
Date: Mon, 13 Dec 2021 14:50:41 -0800
Subject: [PATCH 3/7] Bring in another control for trigger

---
 .../Triggers/IsNullOrEmptyStateTrigger.bind   | 31 +++++++++++++++++--
 .../IsNullOrEmptyStateTriggerPage.xaml.cs     | 25 ++++++++++++++-
 .../Triggers/IsNullOrEmptyStateTrigger.cs     |  3 +-
 3 files changed, 54 insertions(+), 5 deletions(-)

diff --git a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
index c4c757366fc..2d03d6c68d4 100644
--- a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
+++ b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
@@ -26,7 +26,6 @@
         <VisualState x:Name="ListEmptyState">
           <VisualState.StateTriggers>
             <triggers:IsNullOrEmptyStateTrigger Value="{Binding Items, ElementName=OurList, Mode=OneWay}"/>
-          <!--<triggers:IsNullOrEmptyStateTrigger Value="{Binding SelectedItem, ElementName=OurList, Mode=OneWay}"/>-->
           </VisualState.StateTriggers>
           <VisualState.Setters>
             <Setter Target="RemoveButton.IsEnabled" Value="False" />
@@ -34,6 +33,18 @@
           </VisualState.Setters>
         </VisualState>
       </VisualStateGroup>
+      <VisualStateGroup x:Name="ListViewStates">
+        <VisualState x:Name="SelectedItemNotNullState" />
+        <VisualState x:Name="SelectedItemNullState">
+            <VisualState.StateTriggers>
+                <triggers:IsNullOrEmptyStateTrigger Value="{Binding SelectedItem, ElementName=SelectList}"/>
+            </VisualState.StateTriggers>
+            <VisualState.Setters>
+                <Setter Target="RemoveSelection.IsEnabled" Value="False" />
+                <Setter Target="SelectionEmptyMessage.Visibility" Value="Visible" />
+            </VisualState.Setters>
+        </VisualState>
+      </VisualStateGroup>
     </VisualStateManager.VisualStateGroups>
 
     <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
@@ -44,7 +55,7 @@
         <TextBlock x:Name="OurTextBoxError" Text="* Required" Foreground="Red" Margin="10 0 0 0" Visibility="Collapsed" VerticalAlignment="Center" />
       </StackPanel>
 
-      <StackPanel Orientation="Horizontal">
+      <StackPanel Orientation="Horizontal" Margin="0,40,0,0">
         <Button x:Name="AddButton" Content="Add" Margin="0 0 10 0"/>
         <Button x:Name="RemoveButton" Content="Remove"/>
       </StackPanel>
@@ -64,7 +75,21 @@
           </Style>
         </ListBox.ItemContainerStyle>
       </ListBox>
+        
+        <Border BorderBrush="Gold" BorderThickness="1" Margin="0,80,0,0">
+            <StackPanel>
+                <Button x:Name="RemoveSelection" Content="Unselect" />
+                <TextBlock x:Name="SelectionEmptyMessage" Text="SelectedItem is empty, select an item" Visibility="Collapsed"
+                            Margin="5,0,0,0"/>
+                <ListView x:Name="SelectList" HorizontalAlignment="Left">
+                    <ListView.Items>
+                        <TextBlock Text="One" />
+                        <TextBlock Text="Two" />
+                        <TextBlock Text="Three" />
+                    </ListView.Items>
+                </ListView>
+            </StackPanel>            
+        </Border>
     </StackPanel>
-
   </Grid>
 </Page>
diff --git a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs
index 7068f902dcb..792451fdf8b 100644
--- a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs
+++ b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs
@@ -16,6 +16,8 @@ public sealed partial class IsNullOrEmptyStateTriggerPage : Page, IXamlRenderLis
         private Button _addButton;
         private Button _removeButton;
         private ListBox _listBox;
+        private Button _unselectButton;
+        private ListView _selectListView;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="IsNullOrEmptyStateTriggerPage"/> class.
@@ -52,6 +54,19 @@ public void OnXamlRendered(FrameworkElement control)
             }
 
             _listBox = control.FindDescendant("OurList") as ListBox;
+
+            _selectListView = control.FindDescendant("SelectList") as ListView;
+            
+            // Hack to programmatically set the SelectedItem to *any* initial value other than null,
+            //      to prime the trigger to self-reflect when control initially loads, and apply appropriate trigger logic
+            _selectListView.SelectedItem = string.Empty;
+
+            if (control.FindDescendant("RemoveSelection") is Button btn3)
+            {
+                _unselectButton = btn3;
+
+                _unselectButton.Click += this.UnselectButton_Click;
+            }
         }
 
         private void AddButton_Click(object sender, RoutedEventArgs e)
@@ -64,10 +79,18 @@ private void AddButton_Click(object sender, RoutedEventArgs e)
 
         private void RemoveButton_Click(object sender, RoutedEventArgs e)
         {
-            if (_listBox != null)
+            if (_listBox != null && _listBox.Items.Count > 0)
             {
                 _listBox.Items.RemoveAt(0);
             }
         }
+
+        private void UnselectButton_Click(object sender, RoutedEventArgs e)
+        {
+            if(_selectListView != null && _selectListView.SelectedItem != null)
+            {
+                _selectListView.SelectedItem = null;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
index a22b06f09bd..8978128f1f5 100644
--- a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
+++ b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Collections;
 using System.Collections.Specialized;
 using Microsoft.Toolkit.Uwp.Helpers;
@@ -48,7 +49,7 @@ private static void OnValuePropertyChanged(DependencyObject d, DependencyPropert
             }
 
             // Try to listen for various notification events
-            // Starting with INorifyCollectionChanged
+            // Starting with INotifyCollectionChanged
             var valNotifyCollection = val as INotifyCollectionChanged;
             if (valNotifyCollection != null)
             {

From 31f1cc41c7f8015b0293684bdb599d978cfb47db Mon Sep 17 00:00:00 2001
From: Darren Batchelor <v-dbatchelor@microsoft.com>
Date: Mon, 13 Dec 2021 15:11:45 -0800
Subject: [PATCH 4/7] unit test not ready for show

---
 .../Test_IsNullOrEmptyStateTrigger.cs         | 40 -------------------
 1 file changed, 40 deletions(-)
 delete mode 100644 UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs

diff --git a/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs b/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs
deleted file mode 100644
index 9dac624ea3e..00000000000
--- a/UnitTests/UnitTests.UWP/UI/Triggers/Test_IsNullOrEmptyStateTrigger.cs
+++ /dev/null
@@ -1,40 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for more information.
-
-using Microsoft.Toolkit.Uwp;
-using Microsoft.Toolkit.Uwp.UI.Triggers;
-using Microsoft.VisualStudio.TestTools.UnitTesting;
-using System.Threading.Tasks;
-using Windows.UI.Xaml;
-using Windows.UI.Xaml.Controls;
-using Windows.UI.Xaml.Data;
-
-namespace UnitTests.UWP.UI.Triggers
-{
-    [TestClass]
-    [TestCategory("Test_IsNullOrEmptyStateTrigger")]
-    public class Test_IsNullOrEmptyStateTrigger : VisualUITestBase
-    {
-        [TestMethod]
-        public async Task IsNullOrEmptyStateTrigger_SelectedItem()
-        {
-            await App.DispatcherQueue.EnqueueAsync(async () =>
-            {
-                var listView = new ListView { Name="myListView"};
-                await SetTestContentAsync(listView);
-                
-                var trigger = new IsNullOrEmptyStateTrigger();
-                Binding nullOrEmptyStateBinding = new Binding();
-                nullOrEmptyStateBinding.Source = this;
-                nullOrEmptyStateBinding.Path = new PropertyPath("SelectedItem");
-                nullOrEmptyStateBinding.Mode = BindingMode.OneWay;
-                BindingOperations.SetBinding(listView, ListView.SelectedItemProperty, nullOrEmptyStateBinding);
-
-                var bol = IsNullOrEmptyStateTrigger.IsActive;
-
-                Assert.AreEqual(true, bol);
-            });
-        }
-    }
-}

From dae06ea58c2eef3aad8da9e8059f8cbba3a83bef Mon Sep 17 00:00:00 2001
From: Darren Batchelor <v-dbatchelor@microsoft.com>
Date: Mon, 13 Dec 2021 17:02:59 -0800
Subject: [PATCH 5/7] Light up IsActive DP

---
 .../Triggers/IsNullOrEmptyStateTrigger.bind   | 31 +++++++++----------
 .../IsNullOrEmptyStateTriggerPage.xaml.cs     |  4 ---
 .../Triggers/IsNullOrEmptyStateTrigger.cs     | 24 ++++++++++++--
 UnitTests/UnitTests.UWP/UnitTests.UWP.csproj  |  1 -
 4 files changed, 37 insertions(+), 23 deletions(-)

diff --git a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
index 2d03d6c68d4..72dd4921a0c 100644
--- a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
+++ b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
@@ -37,7 +37,7 @@
         <VisualState x:Name="SelectedItemNotNullState" />
         <VisualState x:Name="SelectedItemNullState">
             <VisualState.StateTriggers>
-                <triggers:IsNullOrEmptyStateTrigger Value="{Binding SelectedItem, ElementName=SelectList}"/>
+                <triggers:IsNullOrEmptyStateTrigger Value="{Binding SelectedItem, ElementName=SelectList}" IsActive="True"/>
             </VisualState.StateTriggers>
             <VisualState.Setters>
                 <Setter Target="RemoveSelection.IsEnabled" Value="False" />
@@ -75,21 +75,20 @@
           </Style>
         </ListBox.ItemContainerStyle>
       </ListBox>
-        
-        <Border BorderBrush="Gold" BorderThickness="1" Margin="0,80,0,0">
-            <StackPanel>
-                <Button x:Name="RemoveSelection" Content="Unselect" />
-                <TextBlock x:Name="SelectionEmptyMessage" Text="SelectedItem is empty, select an item" Visibility="Collapsed"
-                            Margin="5,0,0,0"/>
-                <ListView x:Name="SelectList" HorizontalAlignment="Left">
-                    <ListView.Items>
-                        <TextBlock Text="One" />
-                        <TextBlock Text="Two" />
-                        <TextBlock Text="Three" />
-                    </ListView.Items>
-                </ListView>
-            </StackPanel>            
-        </Border>
+      <Border BorderBrush="Gold" BorderThickness="1" Margin="0,80,0,0" Width="275">
+        <StackPanel>
+            <Button x:Name="RemoveSelection" Content="Unselect" />
+            <TextBlock x:Name="SelectionEmptyMessage" Text="SelectedItem is empty, select an item" Visibility="Collapsed"
+                        Margin="5,0,0,0"/>
+            <ListView x:Name="SelectList" HorizontalAlignment="Left">
+                <ListView.Items>
+                    <TextBlock Text="One" />
+                    <TextBlock Text="Two" />
+                    <TextBlock Text="Three" />
+                </ListView.Items>
+            </ListView>
+        </StackPanel>            
+      </Border>
     </StackPanel>
   </Grid>
 </Page>
diff --git a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs
index 792451fdf8b..0d80726099b 100644
--- a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs
+++ b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTriggerPage.xaml.cs
@@ -56,10 +56,6 @@ public void OnXamlRendered(FrameworkElement control)
             _listBox = control.FindDescendant("OurList") as ListBox;
 
             _selectListView = control.FindDescendant("SelectList") as ListView;
-            
-            // Hack to programmatically set the SelectedItem to *any* initial value other than null,
-            //      to prime the trigger to self-reflect when control initially loads, and apply appropriate trigger logic
-            _selectListView.SelectedItem = string.Empty;
 
             if (control.FindDescendant("RemoveSelection") is Button btn3)
             {
diff --git a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
index 8978128f1f5..709f7b5d4bb 100644
--- a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
+++ b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
@@ -34,14 +34,34 @@ public object Value
         /// <summary>
         /// Gets a value indicating whether the trigger is active.
         /// </summary>
-        public static bool IsActive { get; private set; }
+        public bool IsActive
+        {
+            get => (bool)GetValue(IsActiveProperty);
+            set => SetValue(IsActiveProperty, value);
+        }
+
+        /// <summary>
+        /// Identifies the <see cref="IsActive"/> DependencyProperty
+        /// Allows user to enable the trigger from XAML
+        /// </summary>
+        public static readonly DependencyProperty IsActiveProperty =
+            DependencyProperty.Register(nameof(IsActive), typeof(bool), typeof(IsNullOrEmptyStateTrigger), new PropertyMetadata(false, OnIsActiveChanged));
+
+        private static void OnIsActiveChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            if (e.NewValue != null && e.NewValue is bool)
+            {
+                var obj = (IsNullOrEmptyStateTrigger)d;
+                obj.SetActive((bool)e.NewValue);
+            }
+        }
 
         private static void OnValuePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
         {
             var obj = (IsNullOrEmptyStateTrigger)d;
             var val = e.NewValue;
 
-            obj.SetActive(IsActive = IsNullOrEmpty(val));
+            obj.SetActive(obj.IsActive = IsNullOrEmpty(val));
 
             if (val == null)
             {
diff --git a/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj b/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj
index 0d5bafa2ad3..cdbb101c62a 100644
--- a/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj
+++ b/UnitTests/UnitTests.UWP/UnitTests.UWP.csproj
@@ -259,7 +259,6 @@
     <Compile Include="UI\Person.cs" />
     <Compile Include="UI\Test_AdvancedCollectionView.cs" />
     <Compile Include="UI\Triggers\Test_ControlSizeTrigger.cs" />
-    <Compile Include="UI\Triggers\Test_IsNullOrEmptyStateTrigger.cs" />
     <Compile Include="VisualUITestBase.cs" />
   </ItemGroup>
   <ItemGroup>

From 50a04028ba89ae2c340a1ef086f3b740af129f52 Mon Sep 17 00:00:00 2001
From: Darren Batchelor <v-dbatchelor@microsoft.com>
Date: Tue, 14 Dec 2021 11:14:03 -0800
Subject: [PATCH 6/7] Finishing touches

---
 .../SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind         | 2 +-
 Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
index 72dd4921a0c..89884f78020 100644
--- a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
+++ b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
@@ -77,7 +77,7 @@
       </ListBox>
       <Border BorderBrush="Gold" BorderThickness="1" Margin="0,80,0,0" Width="275">
         <StackPanel>
-            <Button x:Name="RemoveSelection" Content="Unselect" />
+            <Button x:Name="RemoveSelection" Content="Deselect" />
             <TextBlock x:Name="SelectionEmptyMessage" Text="SelectedItem is empty, select an item" Visibility="Collapsed"
                         Margin="5,0,0,0"/>
             <ListView x:Name="SelectList" HorizontalAlignment="Left">
diff --git a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
index 709f7b5d4bb..97da46dbc9a 100644
--- a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
+++ b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
@@ -32,7 +32,7 @@ public object Value
             DependencyProperty.Register(nameof(Value), typeof(object), typeof(IsNullOrEmptyStateTrigger), new PropertyMetadata(null, OnValuePropertyChanged));
 
         /// <summary>
-        /// Gets a value indicating whether the trigger is active.
+        /// Gets or sets a value indicating whether a trigger is active.
         /// </summary>
         public bool IsActive
         {

From ccb63662aaf65b7053f27c6eae526a2454b1f4a4 Mon Sep 17 00:00:00 2001
From: Darren Batchelor <v-dbatchelor@microsoft.com>
Date: Tue, 21 Dec 2021 11:06:19 -0800
Subject: [PATCH 7/7] call SetActive in ctor

---
 .../Triggers/IsNullOrEmptyStateTrigger.bind   |  2 +-
 .../Triggers/IsNullOrEmptyStateTrigger.cs     | 26 +++----------------
 2 files changed, 4 insertions(+), 24 deletions(-)

diff --git a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
index 89884f78020..8c812d09637 100644
--- a/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
+++ b/Microsoft.Toolkit.Uwp.SampleApp/SamplePages/Triggers/IsNullOrEmptyStateTrigger.bind
@@ -37,7 +37,7 @@
         <VisualState x:Name="SelectedItemNotNullState" />
         <VisualState x:Name="SelectedItemNullState">
             <VisualState.StateTriggers>
-                <triggers:IsNullOrEmptyStateTrigger Value="{Binding SelectedItem, ElementName=SelectList}" IsActive="True"/>
+                <triggers:IsNullOrEmptyStateTrigger Value="{Binding SelectedItem, ElementName=SelectList}"/>
             </VisualState.StateTriggers>
             <VisualState.Setters>
                 <Setter Target="RemoveSelection.IsEnabled" Value="False" />
diff --git a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
index 97da46dbc9a..fb49e0ecfb1 100644
--- a/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
+++ b/Microsoft.Toolkit.Uwp.UI/Triggers/IsNullOrEmptyStateTrigger.cs
@@ -2,7 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
 using System.Collections;
 using System.Collections.Specialized;
 using Microsoft.Toolkit.Uwp.Helpers;
@@ -32,28 +31,11 @@ public object Value
             DependencyProperty.Register(nameof(Value), typeof(object), typeof(IsNullOrEmptyStateTrigger), new PropertyMetadata(null, OnValuePropertyChanged));
 
         /// <summary>
-        /// Gets or sets a value indicating whether a trigger is active.
+        /// Initializes a new instance of the <see cref="IsNullOrEmptyStateTrigger"/> class.
         /// </summary>
-        public bool IsActive
+        public IsNullOrEmptyStateTrigger()
         {
-            get => (bool)GetValue(IsActiveProperty);
-            set => SetValue(IsActiveProperty, value);
-        }
-
-        /// <summary>
-        /// Identifies the <see cref="IsActive"/> DependencyProperty
-        /// Allows user to enable the trigger from XAML
-        /// </summary>
-        public static readonly DependencyProperty IsActiveProperty =
-            DependencyProperty.Register(nameof(IsActive), typeof(bool), typeof(IsNullOrEmptyStateTrigger), new PropertyMetadata(false, OnIsActiveChanged));
-
-        private static void OnIsActiveChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
-        {
-            if (e.NewValue != null && e.NewValue is bool)
-            {
-                var obj = (IsNullOrEmptyStateTrigger)d;
-                obj.SetActive((bool)e.NewValue);
-            }
+            SetActive(true);
         }
 
         private static void OnValuePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
@@ -61,8 +43,6 @@ private static void OnValuePropertyChanged(DependencyObject d, DependencyPropert
             var obj = (IsNullOrEmptyStateTrigger)d;
             var val = e.NewValue;
 
-            obj.SetActive(obj.IsActive = IsNullOrEmpty(val));
-
             if (val == null)
             {
                 return;