"Sticky window" or "Pin window" Feature

source/SylphyHorn/Interop/NativeMethods.cs

@@ -23,5 +23,15 @@ public static class NativeMethods
 
 		[DllImport("Dwmapi.dll")]
 		public static extern void DwmGetColorizationColor([Out] out int pcrColorization, [Out] out bool pfOpaqueBlend);
-	}
+
+        [DllImport("user32.dll")]
+        [return: MarshalAs(UnmanagedType.Bool)]
+        public static extern bool IsWindow(IntPtr hWnd);
+
+        [DllImport("user32.dll")]
+        public static extern int OpenInputDesktop(int dwFlags, bool fInherit, int dwDesiredAccess);
+
+        [DllImport("user32.dll")]
+        public static extern int GetWindowText(int hWnd, StringBuilder text, int count);
+    }
 }

source/SylphyHorn/Models/Helper.cs

@@ -14,6 +14,7 @@
 using MetroRadiance;
 using Microsoft.Win32;
 using SylphyHorn.Interop;
+using VDMHelperCLR.Common;
 
 namespace SylphyHorn.Models
 {
@@ -63,9 +64,54 @@ public static IntPtr GetForegroundWindowEx()
 			var howner = NativeMethods.GetWindow(hwnd, 4 /* GW_OWNER */);
 			return howner == IntPtr.Zero ? hwnd : howner;
 		}
-	}
 
-	internal static class VisualHelper
+        public static bool IsWindow(IntPtr hWnd)
+        {
+            return NativeMethods.IsWindow(hWnd);
+        }
+
+        public static int GetWindowThreadProcessId(IntPtr hWnd)
+        {
+            int processId = 0;
+            NativeMethods.GetWindowThreadProcessId(hWnd, out processId);
+            return processId;
+        }
+
+        public static string GetWindowText(int hWnd)
+        {
+            const int bufferSize = 256;
+            var windowText = new StringBuilder(bufferSize);
+            if (NativeMethods.GetWindowText(hWnd, windowText, bufferSize) > 0) 
+            {
+                return windowText.ToString();
+            }
+
+            return string.Empty;
+        }
+    }
+
+    /*
+    * The VDMHelper need to be a singleton or else it will create multiple instance of the process VDMHelper32.exe
+    * This can cause failure when moving window.
+    */
+    internal class VDMHelper
+    {
+        private static IVdmHelper instancehelper;
+        public static IVdmHelper helper
+        {
+            get
+            {
+                if (instancehelper == null)
+                {
+                    instancehelper = VdmHelperFactory.CreateInstance();
+                    helper.Init();
+                }
+                return instancehelper;
+            }
+        }
+    }
+
+    internal static class VisualHelper
 	{
 		public static void InvokeOnUIDispatcher(Action action, DispatcherPriority priority = DispatcherPriority.Normal)
 		{

source/SylphyHorn/Models/HookService.cs

@@ -21,9 +21,8 @@ public HookService()
 			this.detector.Pressed += this.KeyHookOnPressed;
 			this.detector.Start();
 
-			this.helper = VdmHelperFactory.CreateInstance();
-			this.helper.Init();
-		}
+            this.helper = VDMHelper.helper;
+        }
 
 		public IDisposable Suspend()
 		{
@@ -47,14 +46,14 @@ private void KeyHookOnPressed(object sender, ShortcutKeyPressedEventArgs args)
 			if (ShortcutSettings.MoveLeft.Value != null &&
 				ShortcutSettings.MoveLeft.Value == args.ShortcutKey)
 			{
-				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToLeft());
+				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToLeft()?.MoveSticky());
 				args.Handled = true;
 			}
 
 			if (ShortcutSettings.MoveLeftAndSwitch.Value != null &&
 				ShortcutSettings.MoveLeftAndSwitch.Value == args.ShortcutKey)
 			{
-				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToLeft()?.Switch());
+				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToLeft()?.MoveSticky().Switch());
 				args.Handled = true;
 			}
 
@@ -68,7 +67,7 @@ private void KeyHookOnPressed(object sender, ShortcutKeyPressedEventArgs args)
 			if (ShortcutSettings.MoveRightAndSwitch.Value != null &&
 				ShortcutSettings.MoveRightAndSwitch.Value == args.ShortcutKey)
 			{
-				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToRight()?.Switch());
+				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToRight()?.MoveSticky().Switch());
 				args.Handled = true;
 			}
 
@@ -82,7 +81,7 @@ private void KeyHookOnPressed(object sender, ShortcutKeyPressedEventArgs args)
 			if (ShortcutSettings.MoveNewAndSwitch.Value != null &&
 				ShortcutSettings.MoveNewAndSwitch.Value == args.ShortcutKey)
 			{
-				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToNew()?.Switch());
+				VisualHelper.InvokeOnUIDispatcher(() => this.MoveToNew()?.MoveSticky().Switch());
 				args.Handled = true;
 			}
 
@@ -91,7 +90,7 @@ private void KeyHookOnPressed(object sender, ShortcutKeyPressedEventArgs args)
 			{
 				if (GeneralSettings.OverrideOSDefaultKeyCombination)
 				{
-					VisualHelper.InvokeOnUIDispatcher(() => PrepareSwitchToLeft()?.Switch());
+					VisualHelper.InvokeOnUIDispatcher(() => PrepareSwitchToLeft()?.MoveSticky().Switch());
 					args.Handled = true;
 				}
 			}
@@ -101,11 +100,17 @@ private void KeyHookOnPressed(object sender, ShortcutKeyPressedEventArgs args)
 			{
 				if (GeneralSettings.OverrideOSDefaultKeyCombination)
 				{
-					VisualHelper.InvokeOnUIDispatcher(() => PrepareSwitchToRight()?.Switch());
+					VisualHelper.InvokeOnUIDispatcher(() => PrepareSwitchToRight()?.MoveSticky().Switch());
 					args.Handled = true;
 				}
 			}
-		}
+
+            if (ShortcutSettings.PinWindows.Value != null &&
+                ShortcutSettings.PinWindows.Value == args.ShortcutKey)
+            {
+                VisualHelper.InvokeOnUIDispatcher(() => StickyWindowsManager.Instance.ToggleStickyWindow());
+            }
+        }
 
 		private static VirtualDesktop PrepareSwitchToLeft()
 		{

source/SylphyHorn/Models/NotificationService.cs

@@ -17,7 +17,8 @@ public class NotificationService : IDisposable
 		public NotificationService()
 		{
 			VirtualDesktop.CurrentChanged += this.VirtualDesktopOnCurrentChanged;
-		}
+            StickyWindowsManager.ToggleStickyWindowEvent += this.ShowToggleStickyWindow;
+        }
 
 		private void VirtualDesktopOnCurrentChanged(object sender, VirtualDesktopChangedEventArgs e)
 		{
@@ -29,22 +30,38 @@ private void VirtualDesktopOnCurrentChanged(object sender, VirtualDesktopChanged
 				var newIndex = Array.IndexOf(desktops, e.NewDesktop) + 1;
 
 				this.currentNotificationWindow?.Dispose();
-				this.currentNotificationWindow = ShowWindow(newIndex);
+
+                var vmodel = new NotificationWindowViewModel
+                {
+                    Title = ProductInfo.Title,
+                    Header = "Virtual Desktop Switched",
+                    Body = "Current Desktop: Desktop " + newIndex,
+                };
+                this.currentNotificationWindow = ShowWindow(vmodel);
 			});
 		}
 
-		private static IDisposable ShowWindow(int index)
+
+        private void ShowToggleStickyWindow(object sender, string body)
+        {
+            this.currentNotificationWindow?.Dispose();
+
+            var vmodel = new NotificationWindowViewModel
+            {
+                Title = ProductInfo.Title,
+                Header = "Window Pin Toggled",
+                Body = body
+            };
+            this.currentNotificationWindow = ShowWindow(vmodel);
+        }
+
+		private static IDisposable ShowWindow(NotificationWindowViewModel vm)
 		{
-			var vmodel = new NotificationWindowViewModel
-			{
-				Title = ProductInfo.Title,
-				Header = "Virtual Desktop Switched",
-				Body = "Current Desktop: Desktop " + index,
-			};
+
 			var source = new CancellationTokenSource();
 			var window = new NotificationWindow
 			{
-				DataContext = vmodel,
+				DataContext = vm,
 			};
 			window.Show();
 
@@ -57,6 +74,7 @@ private static IDisposable ShowWindow(int index)
 		public void Dispose()
 		{
 			VirtualDesktop.CurrentChanged -= this.VirtualDesktopOnCurrentChanged;
-		}
+            StickyWindowsManager.ToggleStickyWindowEvent -= this.ShowToggleStickyWindow;
+        }
 	}
 }

source/SylphyHorn/Models/Settings.cs

@@ -75,6 +75,9 @@ public static class ShortcutSettings
         public static SerializableProperty<ShortcutKey?> SwitchToRight { get; }
             = new SerializableProperty<ShortcutKey?>(GetKey(), Providers.Local, new ShortcutKey(Key.Right, Key.LeftCtrl, Key.LWin));
 
+        public static SerializableProperty<ShortcutKey?> PinWindows { get; }
+            = new SerializableProperty<ShortcutKey?>(GetKey(), Providers.Local, new ShortcutKey(Key.P, Key.LeftCtrl, Key.LeftAlt, Key.LWin));
+
 
         private static string GetKey([CallerMemberName] string caller = "")
 		{