Supports millions of row insert or remove.

Added ResetAsync on the VOC.

Author: anagram4wander

AlphaChiTech.Virtualization/PaginationManager.cs

@@ -869,10 +869,21 @@ public int IndexOf(T item)
         /// <param name="count">The count.</param>
         public void OnReset(int count)
         {
+            if(count < 0)
+            {
+                _HasGotCount = false;
+                return;
+            }
+
             CancelAllRequests();
 
+            lock (_PageLock)
+            {
+                DropAllDeltasAndPages();
+            }
+
             ClearOptimizations();
-            _HasGotCount = false;
+            _HasGotCount = true;
 
             if (!IsAsync)
             {
@@ -883,14 +894,7 @@ public void OnReset(int count)
                 this.ProviderAsync.OnReset(count);
             }
 
-            lock (_PageLock)
-            {
-                DropAllDeltasAndPages();
-            }
-
             RaiseCountChanged(true, count);
-
-            GetCount(true);
         }
 
         /// <summary>

AlphaChiTech.Virtualization/Properties/AssemblyInfo.cs

@@ -26,5 +26,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.1.0.0")]
-[assembly: AssemblyFileVersion("1.1.0.0")]
+[assembly: AssemblyVersion("1.1.3.0")]
+[assembly: AssemblyFileVersion("1.1.3.0")]

AlphaChiTech.Virtualization/VirtualizingObservableCollection.cs

@@ -682,10 +682,31 @@ void InternalClear()
         {
             if(this.Provider != null)
             {
-                this.Provider.OnReset(0);
+                this.Provider.OnReset(this.Provider.GetCount(false));
             } else
             {
-                this.ProviderAsync.OnReset(0);
+                this.ProviderAsync.OnReset(Task.Run(() => this.ProviderAsync.Count).Result);
+            }
+        }
+
+        public async void ResetAsync()
+        {
+            if(this.Provider != null)
+            {
+                this.Provider.OnReset(-1);
+
+                Task.Run(() =>
+                    {
+                        int count = this.Provider.GetCount(false);
+                        VirtualizationManager.Instance.RunOnUI(() =>
+                            this.Provider.OnReset(count)
+                        );
+                    });
+               
+            } 
+            else 
+            {
+                this.ProviderAsync.OnReset(await this.ProviderAsync.Count);
             }
         }