Integrate Npp's dark mode APIs

Demo Plugin/NppManagedPluginDemo/Demo.cs

@@ -40,6 +40,13 @@ public static void OnNotification(ScNotification notification)
             {
                 Kbg.Demo.Namespace.Main.doInsertHtmlCloseTag((char)notification.Character);
             }
+
+            // dark mode (de-)activated
+            if (notification.Header.Code == (uint)NppMsg.NPPN_DARKMODECHANGED)
+            {
+                INotepadPPGateway notepad = new NotepadPPGateway();
+                Kbg.Demo.Namespace.Main.ToggleDarkMode(notepad.IsDarkModeEnabled());
+            }
         }
 
         internal static string PluginName { get { return Kbg.Demo.Namespace.Main.PluginName; }}
@@ -177,6 +184,33 @@ static internal void PluginCleanUp()
         {
             Win32.WritePrivateProfileString(sectionName, keyName, doCloseTag ? "1" : "0", iniFilePath);
         }
+
+        static internal void ToggleDarkMode(bool isDark)
+        {
+            if (frmGoToLine != null)
+            {
+                if (isDark)
+                {
+                    IntPtr theme_ptr = notepad.GetDarkModeColors();
+                    if (theme_ptr != IntPtr.Zero)
+                    {
+                        var theme = (DarkModeColors)Marshal.PtrToStructure(theme_ptr, typeof(DarkModeColors));
+                        frmGoToLine.label1.BackColor  = NppDarkMode.BGRToColor(theme.PureBackground);
+                        frmGoToLine.label1.ForeColor  = NppDarkMode.BGRToColor(theme.Text);
+                        frmGoToLine.button1.BackColor = NppDarkMode.BGRToColor(theme.SofterBackground);
+                        frmGoToLine.button1.ForeColor = NppDarkMode.BGRToColor(theme.Text);
+                        Marshal.FreeHGlobal(theme_ptr);
+                    }
+                }
+                else
+                {
+                    frmGoToLine.label1.ResetBackColor();
+                    frmGoToLine.label1.ResetForeColor();
+                    frmGoToLine.button1.ResetBackColor();
+                    frmGoToLine.button1.ResetForeColor();
+                }
+            }
+        }
         #endregion
 
         #region " Menu functions "
@@ -441,6 +475,7 @@ static void DockableDlgDemo()
                     Win32.SendMessage(PluginBase.nppData._nppHandle, (uint) NppMsg.NPPM_SETMENUITEMCHECK, PluginBase._funcItems.Items[idFrmGotToLine]._cmdID, 0);
                 }
             }
+            ToggleDarkMode(notepad.IsDarkModeEnabled());
             frmGoToLine.textBox1.Focus();
         }
         #endregion

Demo Plugin/NppManagedPluginDemo/NppManagedPluginDemo.csproj

@@ -72,6 +72,9 @@
     <Compile Include="..\..\Visual Studio Project Template C#\PluginInfrastructure\ClikeStringArray.cs">
       <Link>PluginInfrastructure\ClikeStringArray.cs</Link>
     </Compile>
+    <Compile Include="..\..\Visual Studio Project Template C#\PluginInfrastructure\DarkMode.cs">
+      <Link>PluginInfrastructure\DarkMode.cs</Link>
+    </Compile>
     <Compile Include="..\..\Visual Studio Project Template C#\PluginInfrastructure\NotepadPPGateway.cs">
       <Link>PluginInfrastructure\NotepadPPGateway.cs</Link>
     </Compile>

Visual Studio Project Template C#/$projectname$.csproj

@@ -74,6 +74,7 @@
     <Compile Include="PluginInfrastructure\Win32.cs" />
     <Compile Include="Main.cs" />
     <Compile Include="PluginInfrastructure\GatewayDomain.cs" />
+    <Compile Include="PluginInfrastructure\DarkMode.cs" />
     <Compile Include="PluginInfrastructure\NotepadPPGateway.cs" />
     <Compile Include="PluginInfrastructure\ScintillaGateway.cs" />
     <Compile Include="PluginInfrastructure\IScintillaGateway.cs" />

Visual Studio Project Template C#/PluginInfrastructure/DarkMode.cs

@@ -0,0 +1,56 @@
+using System;
+using System.Drawing;
+using System.Runtime.InteropServices;
+
+namespace Kbg.NppPluginNET.PluginInfrastructure
+{
+    /// <summary>
+    /// Holds the BGR values of the active dark mode theme.
+    /// <see href "https://github.com/notepad-plus-plus/notepad-plus-plus/blob/master/PowerEditor/src/NppDarkMode.h"/>
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential)]
+    public struct DarkModeColors
+    {
+        public int Background;
+        public int SofterBackground;
+        public int HotBackground;
+        public int PureBackground;
+        public int ErrorBackground;
+        public int Text;
+        public int DarkerText;
+        public int DisabledText;
+        public int LinkText;
+        public int Edge;
+        public int HotEdge;
+        public int DisabledEdge;
+    }
+
+    /// <summary>
+    /// Extends <see cref="NotepadPPGateway"/> with methods implementing Npp's dark mode API.
+    /// </summary>
+    public partial class NotepadPPGateway : INotepadPPGateway
+    {
+        public IntPtr GetDarkModeColors()
+       {
+            DarkModeColors darkModeColors = new DarkModeColors();
+            IntPtr _cbSize = new IntPtr(Marshal.SizeOf(darkModeColors));
+            IntPtr _ptrDarkModeColors = Marshal.AllocHGlobal(_cbSize);
+            Win32.SendMessage(PluginBase.nppData._nppHandle, (uint) NppMsg.NPPM_GETDARKMODECOLORS, _cbSize, _ptrDarkModeColors);
+            return _ptrDarkModeColors;
+        }
+
+        public bool IsDarkModeEnabled()
+        {
+            IntPtr result = Win32.SendMessage(PluginBase.nppData._nppHandle, (uint) NppMsg.NPPM_ISDARKMODEENABLED, Unused, Unused);
+            return ((int)result == 1);
+       }
+    }
+
+    static class NppDarkMode
+    {
+        public static Color BGRToColor(int bgr)
+        {
+            return Color.FromArgb((bgr & 0xFF), ((bgr >> 8) & 0xFF), ((bgr >> 16) & 0xFF));
+        }
+    }
+}

Visual Studio Project Template C#/PluginInfrastructure/Docking_h.cs

@@ -29,6 +29,7 @@ public enum NppTbMsg : uint
         DWS_ICONTAB = 0x00000001,            // Icon for tabs are available
         DWS_ICONBAR = 0x00000002,            // Icon for icon bar are available (currently not supported)
         DWS_ADDINFO = 0x00000004,            // Additional information are in use
+        DWS_USEOWNDARKMODE = 0x00000008,     // Use plugin's own dark mode
         DWS_PARAMSALL = (DWS_ICONTAB | DWS_ICONBAR | DWS_ADDINFO),
 
         // default docking values for first call of plugin

Visual Studio Project Template C#/PluginInfrastructure/Msgs_h.cs

@@ -560,6 +560,21 @@ public enum NppMsg : uint
         /// </summary>
         NPPM_ADDTOOLBARICON_FORDARKMODE = Constants.NPPMSG + 101,
 
+        /// <summary>
+        /// bool NPPM_ISDARKMODEENABLED(0, 0)
+        /// Returns true when Notepad++ Dark Mode is enabled, false when it is not.
+        /// <see href="https://github.com/notepad-plus-plus/notepad-plus-plus/commit/1eb5b10e41d7ab92b60aa32b28d4fe7739d15b53"/>
+        /// </summary>
+        NPPM_ISDARKMODEENABLED = (Constants.NPPMSG + 107),
+
+        /// <summary>
+        /// bool NPPM_GETDARKMODECOLORS (size_t cbSize, NppDarkMode::Colors* returnColors)
+        /// - cbSize must be filled with sizeof(NppDarkMode::Colors).
+        /// - returnColors must be a pre-allocated NppDarkMode::Colors struct.
+        /// Returns true when successful, false otherwise.
+        /// </summary>
+        NPPM_GETDARKMODECOLORS = (Constants.NPPMSG + 108),
+
         RUNCOMMAND_USER = Constants.WM_USER + 3000,
         NPPM_GETFULLCURRENTPATH = RUNCOMMAND_USER + FULL_CURRENT_PATH,
         NPPM_GETCURRENTDIRECTORY = RUNCOMMAND_USER + CURRENT_DIRECTORY,
@@ -805,6 +820,14 @@ public enum NppMsg : uint
         /// </summary>
         NPPN_FILEDELETED = NPPN_FIRST + 26,
 
+        /// <summary>
+        /// To notify plugins that Dark Mode was enabled/disabled
+        /// scnNotification->nmhdr.code = NPPN_DARKMODECHANGED;
+        /// scnNotification->nmhdr.hwndFrom = hwndNpp;
+        /// scnNotification->nmhdr.idFrom = 0;
+        /// </summary>
+        NPPN_DARKMODECHANGED = (NPPN_FIRST + 27)
+
         /* --Autogenerated -- end of section automatically generated from notepad-plus-plus\PowerEditor\src\MISC\PluginsManager\Notepad_plus_msgs.h * */
     }
 }

Visual Studio Project Template C#/PluginInfrastructure/NotepadPPGateway.cs

@@ -13,6 +13,8 @@ public interface INotepadPPGateway
 
 		void AddToolbarIcon(int funcItemsIndex, toolbarIcons icon);
 		void AddToolbarIcon(int funcItemsIndex, Bitmap icon);
+		bool IsDarkModeEnabled();
+		IntPtr GetDarkModeColors();
 		string GetNppPath();
 		string GetPluginConfigPath();
 		string GetCurrentFilePath();
@@ -25,7 +27,7 @@ public interface INotepadPPGateway
 	/// This class holds helpers for sending messages defined in the Msgs_h.cs file. It is at the moment
 	/// incomplete. Please help fill in the blanks.
 	/// </summary>
-	public class NotepadPPGateway : INotepadPPGateway
+	public partial class NotepadPPGateway : INotepadPPGateway
 	{
 		private const int Unused = 0;