Listen to all possible size change events...

Author: Toemsel

.vs/TaskbarHook/v15/.suo

@@ -9,5 +9,10 @@ public struct Rectangle
         public int Top;         // y position of upper-left corner
         public int Right;       // x position of lower-right corner
         public int Bottom;      // y position of lower-right corner
+
+        public bool Equals(Rectangle rectangle) => Left == rectangle.Left &&
+            Right == rectangle.Right &&
+            Top == rectangle.Top &&
+            Bottom == rectangle.Bottom;
     }
 }

TaskbarHook/Rectangle.cs

@@ -32,12 +32,11 @@ public static Taskbar GetTaskbar()
                 return Taskbar.Instance;
 
             IntPtr taskbarHandle = TaskBarHandle;
-            IntPtr sysPageHandle = SysPagerHandle;
 
             if (taskbarHandle == IntPtr.Zero)
                 throw new PlatformNotSupportedException($"The TaskBar cound't be obtained.");
 
-            Taskbar.CreateAndInitialize(taskbarHandle, sysPageHandle);
+            Taskbar.CreateAndInitialize(taskbarHandle);
             return GetTaskbar();
         }
     }

TaskbarHook/TaskBarFactory.cs

@@ -7,38 +7,28 @@ namespace TaskbarHook
     public class Taskbar : IDisposable
     {
         private static WinEventDelegate taskbarResizeDelegate = new WinEventDelegate(TaskBarResizeEvent);
-        private static WinEventDelegate sysPageResizeDelegate = new WinEventDelegate(SysPageResizeEvent);
 
         private Taskbar() { }
 
-        internal static void CreateAndInitialize(IntPtr taskbarHandle, IntPtr sysPageHandle)
+        internal static void CreateAndInitialize(IntPtr taskbarHandle)
         {
             Instance = new Taskbar();
             Instance.Handle = taskbarHandle;
-            Instance.SysPageHandle = sysPageHandle;
             Instance.Rectangle = User32.GetWindowRectangle(Instance.Handle);
-            Instance.SysPageRectangle = User32.GetWindowRectangle(Instance.SysPageHandle);
             Instance.TaskbarResizeHandle = User32.RegisterWindowSizeChangeEvent(Instance.Handle, taskbarResizeDelegate);
-            Instance.SysPageResizeHandle = User32.RegisterWindowElementAdded(Instance.SysPageHandle, sysPageResizeDelegate);
         }
 
         internal static Taskbar Instance { get; private set; }
 
         public IntPtr Handle { get; private set; }
 
-        private IntPtr SysPageHandle { get; set; }
-
-        private IntPtr TaskbarResizeHandle { get; set; }
-
-        private IntPtr SysPageResizeHandle { get; set; }
-
         public Rectangle Rectangle { get; private set; }
 
-        private Rectangle SysPageRectangle { get; set; }
+        public async Task<TaskbarElement> AddToTaskbar() => await AddToTaskbar(Process.GetCurrentProcess());
 
         public Action SizeChanged { get; set; }
 
-        public async Task<TaskbarElement> AddToTaskbar() => await AddToTaskbar(Process.GetCurrentProcess());
+        private IntPtr TaskbarResizeHandle { get; set; }
 
         public async Task<TaskbarElement> AddToTaskbar(Process process)
         {
@@ -53,29 +43,14 @@ public async Task<TaskbarElement> AddToTaskbar(Process process)
 
         private static void TaskBarResizeEvent(IntPtr hWinEventHook, uint eventType, IntPtr hwnd, int idObject, int idChild, uint dwEventThread, uint dwmsEventTime)
         {
-            Instance.Rectangle = User32.GetWindowRectangle(Instance.Handle);
-            Instance?.SizeChanged?.Invoke();
-        }
-
-        private static void SysPageResizeEvent(IntPtr hWinEventHook, uint eventType, IntPtr hwnd, int idObject, int idChild, uint dwEventThread, uint dwmsEventTime)
-        {
-            var currentIconTrayRectangle = User32.GetWindowRectangle(Instance.SysPageHandle);
-            int width = currentIconTrayRectangle.Right - currentIconTrayRectangle.Left;
-            int height = currentIconTrayRectangle.Bottom - currentIconTrayRectangle.Top;
-            int cwidth = Instance.SysPageRectangle.Right - Instance.SysPageRectangle.Left;
-            int cheight = Instance.SysPageRectangle.Bottom - Instance.SysPageRectangle.Top;
+            var currentRectangle = User32.GetWindowRectangle(Instance.Handle);
+            if (currentRectangle.Equals(Instance.Rectangle))
+                return;
 
-            if (width != cwidth || height != cheight)
-            {
-                Instance.SysPageRectangle = currentIconTrayRectangle;
-                TaskBarResizeEvent(hWinEventHook, eventType, hwnd, idObject, idChild, dwEventThread, dwmsEventTime);
-            }
+            Instance.Rectangle = currentRectangle;
+            Instance?.SizeChanged?.Invoke();
         }
 
-        public void Dispose()
-        {
-            User32.UnRegisterWindowSizeChangeEvent(TaskbarResizeHandle);
-            User32.UnRegisterWindowSizeChangeEvent(SysPageResizeHandle);
-        }
+        public void Dispose() => User32.UnRegisterWindowSizeChangeEvent(TaskbarResizeHandle);
     }
 }

TaskbarHook/Taskbar.cs

@@ -5,8 +5,8 @@ namespace TaskbarHook
 {
     internal static class User32
     {
-        private const uint EVENT_SYSTEM_MOVESIZESTART = 0x000A;
-        private const uint EVENT_SYSTEM_MOVESIZEEND = 0x000B;
+        //private const uint EVENT_SYSTEM_MOVESIZESTART = 0x000A;
+        //private const uint EVENT_SYSTEM_MOVESIZEEND = 0x000B;
         private const uint WINEVENT_OUTOFCONTEXT = 0;
 
         #region DLLImports
@@ -56,7 +56,7 @@ internal static IntPtr RegisterWindowSizeChangeEvent(IntPtr handle, WinEventDele
             uint process, thread = 0;
             thread = GetWindowThreadProcessId(handle, out process);
 
-            return SetWinEventHook(EVENT_SYSTEM_MOVESIZESTART, EVENT_SYSTEM_MOVESIZEEND, IntPtr.Zero, delegateCallback, process, thread, WINEVENT_OUTOFCONTEXT);
+            return SetWinEventHook(0x00001, 0x7FFFF, IntPtr.Zero, delegateCallback, process, thread, WINEVENT_OUTOFCONTEXT);
         }
 
         internal static IntPtr RegisterWindowElementAdded(IntPtr handle, WinEventDelegate delegateCallback)