From 57e749ad67b6fea70038b8df49aeff5ff9c5ada2 Mon Sep 17 00:00:00 2001
From: brianlagunas_cp <XceedBoucherS@users.noreply.github.com>
Date: Wed, 31 Aug 2011 01:33:34 +0000
Subject: [PATCH] CheckListBox: fixed bug where CheckedItems would be null when
 setting the items source.

---
 .../Implementation/CheckListBox.cs            | 34 +++++++++++++------
 1 file changed, 24 insertions(+), 10 deletions(-)

diff --git a/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CheckListBox/Implementation/CheckListBox.cs b/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CheckListBox/Implementation/CheckListBox.cs
index 31a30636..38232f9f 100644
--- a/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CheckListBox/Implementation/CheckListBox.cs
+++ b/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/CheckListBox/Implementation/CheckListBox.cs
@@ -64,7 +64,7 @@ namespace Microsoft.Windows.Controls
 
         protected virtual void OnCheckedItemChanged(object oldValue, object newValue)
         {
-            
+
         }
 
         #endregion //CheckedItem
@@ -115,28 +115,40 @@ namespace Microsoft.Windows.Controls
 
         #endregion //Events
 
-        void CheckListBox_Checked(object sender, RoutedEventArgs e)
+        #region Methods
+
+        private void CheckListBox_Checked(object sender, RoutedEventArgs e)
         {
-            SetCheckedItem(e.OriginalSource);
-            CheckedItems.Add(CheckedItem);
+            var item = GetDataContextItem(e.OriginalSource);
+            SetCheckedItem(item);
+            CheckedItems.Add(item);
             OnCheckedChanged();
         }
 
-        void CheckListBox_Unchecked(object sender, RoutedEventArgs e)
+        private void CheckListBox_Unchecked(object sender, RoutedEventArgs e)
         {
-            SetCheckedItem(e.OriginalSource);
-            CheckedItems.Remove(CheckedItem);
+            var item = GetDataContextItem(e.OriginalSource);
+            SetCheckedItem(item);
+            CheckedItems.Remove(item);
             OnCheckedChanged();
         }
 
+        private object GetDataContextItem(object source)
+        {
+            var selectedCheckListBoxItem = source as FrameworkElement;
+
+            if (selectedCheckListBoxItem != null)
+                return selectedCheckListBoxItem.DataContext;
+            else
+                return null;
+        }
+
         private void SetCheckedItem(object source)
         {
             if (_surpressSelectionChanged)
                 return;
 
-            var selectedCheckListBoxItem = source as FrameworkElement;
-            if (selectedCheckListBoxItem != null)
-                CheckedItem = selectedCheckListBoxItem.DataContext;
+            CheckedItem = source;
         }
 
         private void OnCheckedChanged()
@@ -149,5 +161,7 @@ namespace Microsoft.Windows.Controls
             if (Command != null)
                 Command.Execute(CheckedItem);
         }
+
+        #endregion //Methods
     }
 }