Global hotkeys to toggle visibility + completely hide the GUI (#5)

Register global hotkeys to toggle visibility and stealth mode (hiding the app window), by @timmolderez

Win11ClockTogglerGUI/Win11ClockTogglerGUI.cs

@@ -3,11 +3,14 @@
 using System.Windows.Forms;
 using System.Collections.Generic;
 using Win11ClockToggler;
+using System.Runtime.InteropServices;
 
 namespace Win11ClockTogglerGUI
 {
     public partial class Win11ClockTogglerGUI : Form
     {
+        [DllImport("user32.dll")]
+        public static extern bool RegisterHotKey(IntPtr hWnd, int id, int fsModifiers, int vlc);
 
         private bool IsDirty = false;
         private List<IntPtr> CurrentMonitoredControls = new List<IntPtr>();
@@ -16,9 +19,17 @@ public partial class Win11ClockTogglerGUI : Form
         private readonly string REG_CHKNOTIFAREA_STATUS = "chkNotifArea_Status";
         private readonly string REG_CHKALLLDISPLAYS_STATUS = "chkAllDisplays_Status";
 
+        private static int TOGGLE_KEY_ID = 1;
+        private static int STEALTH_KEY_ID = 2;
+
         public Win11ClockTogglerGUI()
         {
             InitializeComponent();
+
+            // Register hotkeys
+            int keyModifiers = 0x008 + 0x004; // Win + Shift
+            RegisterHotKey(this.Handle, TOGGLE_KEY_ID, keyModifiers, (int)Keys.F6);
+            RegisterHotKey(this.Handle, STEALTH_KEY_ID, keyModifiers, (int)Keys.F7);
         }
 
         private void CheckBoxes_Paint(object sender, PaintEventArgs e)
@@ -40,6 +51,47 @@ private void btnExit_Click(object sender, EventArgs e)
             this.Close();
         }
 
+        // Process any messages sent to this window
+        protected override void WndProc(ref Message m)
+        {
+            bool passThroughMsg = true;
+
+            // Catch the WM_HOTKEY message to handle any hotkeys being pressed
+            // https://docs.microsoft.com/en-us/windows/win32/inputdev/wm-hotkey
+            const int WM_HOTKEY = 0x0312;
+            if (m.Msg == WM_HOTKEY)
+            {
+                int id = m.WParam.ToInt32();
+                if (id == TOGGLE_KEY_ID) 
+                {
+                    btnHideShow_Click(null, null);
+                }
+                else if (id == STEALTH_KEY_ID) 
+                {
+                    toggleStealthMode();
+                }
+            }
+
+            // Catch the WM_SYSCOMMAND message
+            // https://docs.microsoft.com/en-us/windows/win32/menurc/wm-syscommand
+            const int WM_SYSCOMMAND = 0x0112;
+            if (m.Msg == WM_SYSCOMMAND)
+            {
+                // When the window is being minimized (SC_MINIMIZE)
+                const int SC_MINIMIZE = 0xf020;
+                if (m.WParam.ToInt32() == SC_MINIMIZE)
+                {
+                    passThroughMsg = false; // To prevent the regular minimize behaviour
+                    toggleStealthMode(); 
+                }
+            }
+
+            if (passThroughMsg)
+            {
+                base.WndProc(ref m);
+            }
+        }
+
         private void btnHideShow_Click(object sender, EventArgs e)
         {
             //By default, hide at least the clock
@@ -110,7 +162,7 @@ private void Win11ClockTogglerGUI_Load(object sender, EventArgs e)
 
             //Check if there are secondary taskbars in secondary windows
             if (!Helper.AreThereSecondaryTaskbars())
-            { 
+            {
                 //Disable checkbox if there are not secondary taskbars
                 chkSecondary.Checked = false;
                 DisableCheckBox(chkSecondary);
@@ -141,6 +193,22 @@ private void Win11ClockTogglerGUI_FormClosing(object sender, FormClosingEventArg
             }
         }
 
+        private void toggleStealthMode()
+        {
+            if (Visible)
+            {
+                Hide();
+                MessageBox.Show("The Win11ClockToggler window is now completely hidden.\nWhenever you want to bring it back, press Win+Shift+F7.");
+
+            }
+            else
+            {
+                Show();
+                this.WindowState = FormWindowState.Normal;
+                BringToFront();
+            }
+        }
+
         //Timer to monitor if the current notification area pops up again because of a new icon or notification
         private void tmrShowMonitor_Tick(object sender, EventArgs e)
         {