Fix issue：https://gitee.com/WPFDevelopersOrg/WPFDevelopers/issues/ICN2GG

Display Meesage at the top of the external window

Author: yanjinhuagood

src/WPFDevelopers.Shared/Controls/Message/Message.cs

@@ -40,16 +40,22 @@ static void CreateMessageAdorner(Window owner = null, string message = null, Mes
                 throw;
             }
         }
+
         public static void Push(this Window owner, string message, MessageBoxImage type = MessageBoxImage.Information, bool center = false)
         {
             CreateMessageAdorner(owner, message, type, center);
         }
+
         public static void Push(string message, MessageBoxImage type = MessageBoxImage.Information, bool center = false)
         {
             CreateMessageAdorner(message: message, type: type, center: center);
         }
+        public static void Push(IntPtr intPtr, string message, MessageBoxImage type = MessageBoxImage.Information, bool center = false)
+        {
+            PushDesktop(message, type, center, intPtr);
+        }
 
-        public static void PushDesktop(string message, MessageBoxImage type = MessageBoxImage.Information, bool center = false)
+        public static void PushDesktop(string message, MessageBoxImage type = MessageBoxImage.Information, bool center = false, IntPtr intPtr = default)
         {
             if (_messageExt == null)
             {
@@ -63,13 +69,15 @@ public static void PushDesktop(string message, MessageBoxImage type = MessageBox
                 _messageExt.IsPosition = false;
                 _messageExt.Position = _position;
             }
-            _messageExt.Push(message, type, center); 
+            _messageExt.Push(message, type, center, intPtr);
         }
+
         public static void SetPosition(Position position = Position.Top)
         {
             if (_position != position)
                 _position = position;
         }
+
         public static void Clear()
         {
             if(_messageAdorner != null)

src/WPFDevelopers.Shared/Controls/Message/MessageExt.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Windows;
 using System.Windows.Media;
+using WPFDevelopers.Helpers;
 
 namespace WPFDevelopers.Controls
 {
@@ -30,43 +31,76 @@ public MessageExt()
             }
 
         }
-        
-        internal void Push(string message, MessageBoxImage type = MessageBoxImage.Information, bool center = false)
+
+        internal void Push(string message, MessageBoxImage type = MessageBoxImage.Information,
+                  bool center = false, IntPtr intPtr = default)
         {
-            var desktopWorkingArea = SystemParameters.WorkArea;
-            var item = new MessageListBoxItem { Content = message, MessageType = type, IsCenter = center };
-            _listBox.Items.Insert(0, item);
+            Rect targetArea = GetTargetArea(intPtr);
+            var messageItem = new MessageListBoxItem
+            {
+                Content = message,
+                MessageType = type,
+                IsCenter = center
+            };
+            _listBox.Items.Insert(0, messageItem);
             if (!IsPosition || Position == Position.Bottom)
             {
-                double x = 0;
-                double y = 0;
-                switch (Position)
-                {
-                    case Position.Top:
-                        x = (desktopWorkingArea.Right - item.Width) / 2;
-                        break;
-                    case Position.Right:
-                        x = desktopWorkingArea.Right - (item.Width + item.Margin.Right + item.Padding.Right);
-                        break;
-                    case Position.Bottom:
-                        x = (desktopWorkingArea.Right - item.Width) / 2;
-                        _listBox.Measure(new Size(double.PositiveInfinity, double.PositiveInfinity));
-                        var controlHeight = _listBox.DesiredSize.Height;
-                        y = desktopWorkingArea.Height - controlHeight;
-                        break;
-                }
-                Height = desktopWorkingArea.Height;
-                Left = x;
-                Top = y;
+                CalculateAndSetPosition(targetArea, messageItem);
                 IsPosition = true;
             }
         }
+
+        private Rect GetTargetArea(IntPtr windowHandle)
+        {
+            if (windowHandle != IntPtr.Zero)
+            {
+                IsPosition = false;
+                return WindowHelpers.GetWindowBounds(windowHandle);
+            }
+            return SystemParameters.WorkArea;
+        }
+
+        private void CalculateAndSetPosition(Rect targetArea, MessageListBoxItem item)
+        {
+            double x = 0;
+            double y = 0;
+
+            switch (Position)
+            {
+                case Position.Left:
+                    x = targetArea.Left + item.Margin.Left;
+                    y = targetArea.Top;
+                    break;
+
+                case Position.Top:
+                    x = targetArea.Left + (targetArea.Width - item.Width) / 2;
+                    y = targetArea.Top;
+                    break;
+
+                case Position.Right:
+                    x = targetArea.Right - (item.Width + item.Margin.Right + item.Padding.Right);
+                    y = targetArea.Top;
+                    break;
+
+                case Position.Bottom:
+                    x = targetArea.Left + (targetArea.Width - item.Width) / 2;
+                    _listBox.Measure(new Size(double.PositiveInfinity, double.PositiveInfinity));
+                    y = targetArea.Bottom - _listBox.DesiredSize.Height;
+                    break;
+            }
+
+            Height = targetArea.Height;
+            Left = x;
+            Top = y;
+        }
+
         internal void Clear() 
         {
             if(_listBox!=null)
                 _listBox.Items.Clear();
             Close();
         }
+
         private void ListBox_SizeChanged(object sender, SizeChangedEventArgs e)
         {
             if(_listBox.ActualHeight <= 10)

src/WPFDevelopers.Shared/Core/Helpers/Win32.cs

@@ -17,7 +17,7 @@ public const string
             NTdll = "ntdll.dll",
             DwmApi = "dwmapi.dll",
             Winmm = "winmm.dll",
-            Shcore = "Shcore.dll";
+            Shcore = "shcore.dll";
         //查找窗口的委托 查找逻辑
         public delegate bool EnumWindowsProc(IntPtr hwnd, IntPtr lParam);
 
@@ -192,6 +192,20 @@ public static bool EnableDarkModeForWindow(HwndSource source, bool enable)
         [DllImport(DwmApi)]
         public static extern int DwmInvalidateIconicBitmaps(IntPtr hwnd);
 
+        [DllImport(User32)]
+        public static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);
+
+        [DllImport(User32)]
+        public static extern int GetDpiForWindow(IntPtr hwnd);
+
+        [StructLayout(LayoutKind.Sequential)]
+        public struct RECT
+        {
+            public int Left;
+            public int Top;
+            public int Right;
+            public int Bottom;
+        }
     }
 
     internal class WindowsMessageCodes

src/WPFDevelopers.Shared/Core/Helpers/WindowHelpers.cs

@@ -5,6 +5,7 @@
 using System.Windows;
 using System.Windows.Interop;
 using System.Windows.Media;
+using System.Windows.Threading;
 using WPFDevelopers.Controls;
 using WPFDevelopers.Utilities;
 using Size = System.Drawing.Size;
@@ -95,5 +96,18 @@ public static void SetIconicThumbnail(this Window window, string imagePath)
             Win32.DwmInvalidateIconicBitmaps(hwnd);
             window.ShowInTaskbar = true;
         }
+
+        public static Rect GetWindowBounds(IntPtr hWnd)
+        {
+            Win32.RECT rect;
+            Win32.GetWindowRect(hWnd, out rect);
+            int dpi = Win32.GetDpiForWindow(hWnd);
+            double scale = dpi / 96.0;
+            return new Rect(
+                rect.Left / scale,
+                rect.Top / scale,
+                (rect.Right - rect.Left) / scale,
+                (rect.Bottom - rect.Top) / scale);
+        }
     }
 }