Implement Explorer.exe monitoring feature.

RetroBar/Utilities/ExplorerMonitor.cs

@@ -0,0 +1,58 @@
+using ManagedShell.Common.Logging;
+using ManagedShell.Interop;
+using System;
+using System.Windows.Forms;
+
+namespace RetroBar.Utilities
+{
+    public class ExplorerMonitor : IDisposable
+    {
+        private ExplorerMonitorWindow _explorerMonitorWindow;
+
+        public void ExplorerMonitorStart(WindowManager windowManagerRef)
+        {
+            if (_explorerMonitorWindow != null) { return; } // Prevent multiple monitors.
+
+            _explorerMonitorWindow = new ExplorerMonitorWindow(windowManagerRef); // Start monitoring.
+        }
+
+        public void Dispose()
+        {
+            _explorerMonitorWindow?.Dispose();
+        }
+
+        private class ExplorerMonitorWindow : NativeWindow, IDisposable
+        {
+            private readonly WindowManager _windowManagerRef;
+            private static readonly int WM_TASKBARCREATEDMESSAGE = NativeMethods.RegisterWindowMessage("TaskbarCreated");
+
+            public ExplorerMonitorWindow(WindowManager windowManagerRef)
+            {
+                _windowManagerRef = windowManagerRef;
+                CreateHandle(new CreateParams());
+            }
+
+            protected override void WndProc(ref Message m)
+            {
+                if (m.Msg == WM_TASKBARCREATEDMESSAGE)
+                {
+                    try
+                    {
+                        _windowManagerRef.ReopenTaskbars(); // Reopen taskbars if explorer.exe is restarted.
+                    }
+                    catch (Exception ex)
+                    {
+                        ShellLogger.Warning($"Error handling TaskbarCreated message on ExplorerMonitor: {ex.Message}");
+                    }
+                }
+
+                base.WndProc(ref m); // Call the base class to process other messages so we dont accidentally cause crashes or bugs.
+            }
+
+            public void Dispose()
+            {
+                DestroyHandle();
+            }
+        }
+    }
+}

RetroBar/Utilities/WindowManager.cs

@@ -1,4 +1,4 @@
-using ManagedShell;
+using ManagedShell;
 using ManagedShell.AppBar;
 using ManagedShell.Common.Logging;
 using System;
@@ -18,12 +18,16 @@ public class WindowManager : IDisposable
         private readonly ShellManager _shellManager;
         private readonly Updater _updater;
 
+        private readonly ExplorerMonitor _explorerMonitor = new();
+
         public WindowManager(ShellManager shellManager, StartMenuMonitor startMenuMonitor, Updater updater)
         {
             _shellManager = shellManager;
             _startMenuMonitor = startMenuMonitor;
             _updater = updater;
 
+            _explorerMonitor.ExplorerMonitorStart(this);
+
             _shellManager.ExplorerHelper.HideExplorerTaskbar = true;
 
             openTaskbars();
@@ -183,6 +187,7 @@ private void resetScreenCache()
 
         public void Dispose()
         {
+            _explorerMonitor?.Dispose();
             _shellManager.ExplorerHelper.HideExplorerTaskbar = false;
             Settings.Instance.PropertyChanged -= Settings_PropertyChanged;
         }