diff --git a/src/ObservableCollections/ISynchronizedViewFilter.cs b/src/ObservableCollections/ISynchronizedViewFilter.cs
index 9f4b32b..0a080a9 100644
--- a/src/ObservableCollections/ISynchronizedViewFilter.cs
+++ b/src/ObservableCollections/ISynchronizedViewFilter.cs
@@ -81,7 +81,7 @@ namespace ObservableCollections
                 filteredCount--;
                 if (ev != null)
                 {
-                    ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Remove, isMatch, oldValue: value, oldView: view, oldViewIndex: oldIndex));
+                    ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Remove, oldValue: value, oldView: view, oldViewIndex: oldIndex));
                 }
             }
         }
@@ -115,26 +115,31 @@ namespace ObservableCollections
             var newMatched = collection.CurrentFilter.IsMatch(value);
             var bothMatched = oldMatched && newMatched;
 
-            // TODO:...!
             if (bothMatched)
             {
+                if (ev != null)
+                {
+                    ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Replace, newValue: value, newView: view, oldValue: oldValue, oldView: oldView, newViewIndex: index, oldViewIndex: oldIndex >= 0 ? oldIndex : index));
+                }
             }
             else if (oldMatched)
             {
                 // only-old is remove
+                filteredCount--;
+                if (ev != null)
+                {
+                    ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Remove, oldValue: value, oldView: view, oldViewIndex: oldIndex));
+                }
+
             }
             else if (newMatched)
             {
                 // only-new is add
-            }
-
-
-
-
-            if (ev != null)
-            {
-                var isMatch = collection.CurrentFilter.IsMatch(value);
-                ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Replace, isMatch, newValue: value, newView: view, oldValue: oldValue, oldView: oldView, newViewIndex: index, oldViewIndex: oldIndex >= 0 ? oldIndex : index));
+                filteredCount++;
+                if (ev != null)
+                {
+                    ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Add, newValue: value, newView: view, newViewIndex: index));
+                }
             }
         }
 
@@ -143,19 +148,7 @@ namespace ObservableCollections
             filteredCount = 0;
             if (ev != null)
             {
-                ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Reset, true));
-            }
-        }
-
-        internal static void InvokeOnAttach<T, TView>(this ISynchronizedViewFilter<T, TView> filter, T value, TView view)
-        {
-            if (filter.IsMatch(value, view))
-            {
-                filter.WhenTrue(value, view);
-            }
-            else
-            {
-                filter.WhenFalse(value, view);
+                ev.Invoke(new SynchronizedViewChangedEventArgs<T, TView>(NotifyCollectionChangedAction.Reset));
             }
         }
     }
diff --git a/src/ObservableCollections/ObservableList.Views.cs b/src/ObservableCollections/ObservableList.Views.cs
index eac67a2..8ec2beb 100644
--- a/src/ObservableCollections/ObservableList.Views.cs
+++ b/src/ObservableCollections/ObservableList.Views.cs
@@ -16,7 +16,7 @@ namespace ObservableCollections
 
         internal sealed class View<TView> : ISynchronizedView<T, TView>
         {
-            public ISynchronizedViewFilter<T, TView> CurrentFilter
+            public ISynchronizedViewFilter<T> CurrentFilter
             {
                 get
                 {
@@ -30,10 +30,9 @@ namespace ObservableCollections
             readonly List<(T, TView)> list;
             int filteredCount;
 
-            ISynchronizedViewFilter<T, TView> filter;
+            ISynchronizedViewFilter<T> filter;
 
             public event Action<SynchronizedViewChangedEventArgs<T, TView>>? ViewChanged;
-            // public event NotifyCollectionChangedEventHandler<T>? RoutingCollectionChanged;
             public event Action<NotifyCollectionChangedAction>? CollectionStateChanged;
 
             public object SyncRoot { get; }
@@ -43,7 +42,7 @@ namespace ObservableCollections
                 this.source = source;
                 this.selector = selector;
                 this.reverse = reverse;
-                this.filter = SynchronizedViewFilter<T, TView>.Null;
+                this.filter = SynchronizedViewFilter<T>.Null;
                 this.SyncRoot = new object();
                 lock (source.SyncRoot)
                 {
@@ -64,7 +63,7 @@ namespace ObservableCollections
                 }
             }
 
-            public void AttachFilter(ISynchronizedViewFilter<T, TView> filter, bool invokeAddEventForCurrentElements = false)
+            public void AttachFilter(ISynchronizedViewFilter<T> filter, bool invokeAddEventForCurrentElements = false)
             {
                 lock (SyncRoot)
                 {
@@ -84,11 +83,11 @@ namespace ObservableCollections
                 }
             }
 
-            public void ResetFilter(Action<T, TView>? resetAction)
+            public void ResetFilter(Action<T>? resetAction)
             {
                 lock (SyncRoot)
                 {
-                    this.filter = SynchronizedViewFilter<T, TView>.Null;
+                    this.filter = SynchronizedViewFilter<T>.Null;
                     if (resetAction != null)
                     {
                         foreach (var (item, view) in list)