Windows 10 Dark Mode & VB6 apps

[Mith]

VB6SP6, VBCCR17, Win10 (latest) & Dark Mode acitvated

Does anybody know how to activate the windows 10 dark mode for an vb6-app?

I already set the background color of the app window myself and change the background color of the most controls but i dont know how change the color of the window title bar or the scrollbars.

I guess there must be some windows theme API that can activate the dark mode for the window and maybe the controls too?

[dilettante]

That Dark Mode has limited support outside of Metro/WinRT/UWP "Store Apps." A few other things like File Explorer and Edge support it, but I don't think the APIs for that were ever published.

[fafalone]

For the title bar, try this:

Public Declare Function DwmSetWindowAttribute Lib "uxtheme" (ByVal hWnd As Long, ByVal dwAttribute As Long, pvAttribute As Any, ByVal cbAttribute As Long) As Long

Const DWMWA_USE_IMMERSIVE_DARK_MODE = 20
Dim bValue As Long: bValue = 1
DwmSetWindowAttribute hWnd, DWMWA_USE_IMMERSIVE_DARK_MODE, bValue, LenB(bValue)

or this:

Public Declare Function SetWindowCompositionAttribute Lib "user32" (ByVal hWnd As Long, wca As WINDOWCOMPOSITIONATTRIBDATA) As Long
Public Type WINDOWCOMPOSITIONATTRIBDATA
	Attrib As WINDOWCOMPOSITIONATTRIB
	pvData As Long
	cbData As Long
End Type

Const WCA_USEDARKMODECOLORS=26
Dim tWCAD As WINDOWCOMPOSITIONATTRIBDATA
Dim bValue As Long: bValue = 1
tWCAD.Attrib = WCA_USEDARKMODECOLORS
tWCAD.pvData = VarPtr(bValue)
tWCAD.cbData = LenB(bValue)
SetWindowCompositionAttribute hWnd, tWCAD

Scroll bars look harder... this might help.

[Mith]

[QUOTE]

Public Declare Function DwmSetWindowAttribute Lib "uxtheme" (ByVal hWnd As Long, ByVal dwAttribute As Long, pvAttribute As Any, ByVal cbAttribute As Long) As Long

i get the error "Entry point not found" with this API declaration...

Public Type WINDOWCOMPOSITIONATTRIBDATA
	Attrib As WINDOWCOMPOSITIONATTRIB
	pvData As Long
	cbData As Long
End Type

The line "Attrib As WINDOWCOMPOSITIONATTRIB" throws the error "user-defined type not defined"...

[Mith]

@fafalone

i used this modified code from your #1 example but it doesnt change the title bar of the form:

Private Declare Function DwmSetWindowAttribute Lib "dwmapi.dll" (ByVal hWnd As Long, ByVal dwAttribute As Long, ByRef pvAttribute As Long, ByVal cbAttribute As Long) As Long
Private Const DWMWA_USE_IMMERSIVE_DARK_MODE = 20 

Private Sub Form_Load()
 Dim bValue As Long
 bValue = 1
 Call DwmSetWindowAttribute(Me.hWnd, DWMWA_USE_IMMERSIVE_DARK_MODE, bValue, LenB(bValue))
End Sub

i also tried this modified code from your #2 example but the title bar of the form doesnt change too:

Public Declare Function SetWindowCompositionAttribute Lib "user32" (ByVal hWnd As Long, wca As WINDOWCOMPOSITIONATTRIBDATA) As Long
Private Enum WINDOWCOMPOSITIONATTRIB
    WCA_UNDEFINED = 0
    WCA_NCRENDERING_ENABLED = 1
    WCA_NCRENDERING_POLICY = 2
    WCA_TRANSITIONS_FORCEDISABLED = 3
    WCA_ALLOW_NCPAINT = 4
    WCA_CAPTION_BUTTON_BOUNDS = 5
    WCA_NONCLIENT_RTL_LAYOUT = 6
    WCA_FORCE_ICONIC_REPRESENTATION = 7
    WCA_EXTENDED_FRAME_BOUNDS = 8
    WCA_HAS_ICONIC_BITMAP = 9
    WCA_THEME_ATTRIBUTES = 10
    WCA_NCRENDERING_EXILED = 11
    WCA_NCADORNMENTINFO = 12
    WCA_EXCLUDED_FROM_LIVEPREVIEW = 13
    WCA_VIDEO_OVERLAY_ACTIVE = 14
    WCA_FORCE_ACTIVEWINDOW_APPEARANCE = 15
    WCA_DISALLOW_PEEK = 16
    WCA_CLOAK = 17
    WCA_CLOAKED = 18
    WCA_ACCENT_POLICY = 19
    WCA_FREEZE_REPRESENTATION = 20
    WCA_EVER_UNCLOAKED = 21
    WCA_VISUAL_OWNER = 22
    WCA_LAST = 23
End Enum
Private Type WINDOWCOMPOSITIONATTRIBDATA
   Attrib As WINDOWCOMPOSITIONATTRIB
   pvData As Long
   cbData As Long
End Type
Const WCA_USEDARKMODECOLORS = 26

Private Sub Form_Load()
 Dim tWCAD As WINDOWCOMPOSITIONATTRIBDATA
 Dim bValue As Long
 bValue = 1
 tWCAD.Attrib = WCA_USEDARKMODECOLORS
 tWCAD.pvData = VarPtr(bValue)
 tWCAD.cbData = LenB(bValue)
 SetWindowCompositionAttribute Me.hWnd, tWCAD
End Sub

i tried both examples in the VB6 IDE and as a compilied exe.
The Win10 dark mode was activated when running the tests.

any ideas or suggestions?

[Mith]

That Dark Mode has limited support outside of Metro/WinRT/UWP "Store Apps." A few other things like File Explorer and Edge support it, but I don't think the APIs for that were ever published.

I found a Github project that enables Dark Mode support for win32 apps but i dont know how to convert the used APIs into VB6 language:
https://github.com/komiyamma/win32-darkmode

#pragma once
#include "IatHook.h"

enum IMMERSIVE_HC_CACHE_MODE
{
	IHCM_USE_CACHED_VALUE,
	IHCM_REFRESH
};

// 1903 18362
enum PreferredAppMode
{
	Default,
	AllowDark,
	ForceDark,
	ForceLight,
	Max
};

enum WINDOWCOMPOSITIONATTRIB
{
	WCA_UNDEFINED = 0,
	WCA_NCRENDERING_ENABLED = 1,
	WCA_NCRENDERING_POLICY = 2,
	WCA_TRANSITIONS_FORCEDISABLED = 3,
	WCA_ALLOW_NCPAINT = 4,
	WCA_CAPTION_BUTTON_BOUNDS = 5,
	WCA_NONCLIENT_RTL_LAYOUT = 6,
	WCA_FORCE_ICONIC_REPRESENTATION = 7,
	WCA_EXTENDED_FRAME_BOUNDS = 8,
	WCA_HAS_ICONIC_BITMAP = 9,
	WCA_THEME_ATTRIBUTES = 10,
	WCA_NCRENDERING_EXILED = 11,
	WCA_NCADORNMENTINFO = 12,
	WCA_EXCLUDED_FROM_LIVEPREVIEW = 13,
	WCA_VIDEO_OVERLAY_ACTIVE = 14,
	WCA_FORCE_ACTIVEWINDOW_APPEARANCE = 15,
	WCA_DISALLOW_PEEK = 16,
	WCA_CLOAK = 17,
	WCA_CLOAKED = 18,
	WCA_ACCENT_POLICY = 19,
	WCA_FREEZE_REPRESENTATION = 20,
	WCA_EVER_UNCLOAKED = 21,
	WCA_VISUAL_OWNER = 22,
	WCA_HOLOGRAPHIC = 23,
	WCA_EXCLUDED_FROM_DDA = 24,
	WCA_PASSIVEUPDATEMODE = 25,
	WCA_USEDARKMODECOLORS = 26,
	WCA_LAST = 27
};

struct WINDOWCOMPOSITIONATTRIBDATA
{
	WINDOWCOMPOSITIONATTRIB Attrib;
	PVOID pvData;
	SIZE_T cbData;
};

using fnRtlGetNtVersionNumbers = void (WINAPI *)(LPDWORD major, LPDWORD minor, LPDWORD build);
using fnSetWindowCompositionAttribute = BOOL (WINAPI *)(HWND hWnd, WINDOWCOMPOSITIONATTRIBDATA*);
// 1809 17763
using fnShouldAppsUseDarkMode = bool (WINAPI *)(); // ordinal 132
using fnAllowDarkModeForWindow = bool (WINAPI *)(HWND hWnd, bool allow); // ordinal 133
using fnAllowDarkModeForApp = bool (WINAPI *)(bool allow); // ordinal 135, in 1809
using fnFlushMenuThemes = void (WINAPI *)(); // ordinal 136
using fnRefreshImmersiveColorPolicyState = void (WINAPI *)(); // ordinal 104
using fnIsDarkModeAllowedForWindow = bool (WINAPI *)(HWND hWnd); // ordinal 137
using fnGetIsImmersiveColorUsingHighContrast = bool (WINAPI *)(IMMERSIVE_HC_CACHE_MODE mode); // ordinal 106
using fnOpenNcThemeData = HTHEME(WINAPI *)(HWND hWnd, LPCWSTR pszClassList); // ordinal 49
// 1903 18362
using fnShouldSystemUseDarkMode = bool (WINAPI *)(); // ordinal 138
using fnSetPreferredAppMode = PreferredAppMode (WINAPI *)(PreferredAppMode appMode); // ordinal 135, in 1903
using fnIsDarkModeAllowedForApp = bool (WINAPI *)(); // ordinal 139

fnSetWindowCompositionAttribute _SetWindowCompositionAttribute = nullptr;
fnShouldAppsUseDarkMode _ShouldAppsUseDarkMode = nullptr;
fnAllowDarkModeForWindow _AllowDarkModeForWindow = nullptr;
fnAllowDarkModeForApp _AllowDarkModeForApp = nullptr;
fnFlushMenuThemes _FlushMenuThemes = nullptr;
fnRefreshImmersiveColorPolicyState _RefreshImmersiveColorPolicyState = nullptr;
fnIsDarkModeAllowedForWindow _IsDarkModeAllowedForWindow = nullptr;
fnGetIsImmersiveColorUsingHighContrast _GetIsImmersiveColorUsingHighContrast = nullptr;
fnOpenNcThemeData _OpenNcThemeData = nullptr;
// 1903 18362
fnShouldSystemUseDarkMode _ShouldSystemUseDarkMode = nullptr;
fnSetPreferredAppMode _SetPreferredAppMode = nullptr;

bool g_darkModeSupported = false;
bool g_darkModeEnabled = false;
DWORD g_buildNumber = 0;

bool AllowDarkModeForWindow(HWND hWnd, bool allow)
{
	if (g_darkModeSupported)
		return _AllowDarkModeForWindow(hWnd, allow);
	return false;
}

bool IsHighContrast()
{
	HIGHCONTRASTW highContrast = { sizeof(highContrast) };
	if (SystemParametersInfoW(SPI_GETHIGHCONTRAST, sizeof(highContrast), &highContrast, FALSE))
		return highContrast.dwFlags & HCF_HIGHCONTRASTON;
	return false;
}

void RefreshTitleBarThemeColor(HWND hWnd)
{
	BOOL dark = FALSE;
	if (_IsDarkModeAllowedForWindow(hWnd) &&
		_ShouldAppsUseDarkMode() &&
		!IsHighContrast())
	{
		dark = TRUE;
	}
	if (g_buildNumber < 18362)
		SetPropW(hWnd, L"UseImmersiveDarkModeColors", reinterpret_cast<HANDLE>(static_cast<INT_PTR>(dark)));
	else if (_SetWindowCompositionAttribute)
	{
		WINDOWCOMPOSITIONATTRIBDATA data = { WCA_USEDARKMODECOLORS, &dark, sizeof(dark) };
		_SetWindowCompositionAttribute(hWnd, &data);
	}
}

bool IsColorSchemeChangeMessage(LPARAM lParam)
{
	bool is = false;
	if (lParam && CompareStringOrdinal(reinterpret_cast<LPCWCH>(lParam), -1, L"ImmersiveColorSet", -1, TRUE) == CSTR_EQUAL)
	{
		_RefreshImmersiveColorPolicyState();
		is = true;
	}
	_GetIsImmersiveColorUsingHighContrast(IHCM_REFRESH);
	return is;
}

bool IsColorSchemeChangeMessage(UINT message, LPARAM lParam)
{
	if (message == WM_SETTINGCHANGE)
		return IsColorSchemeChangeMessage(lParam);
	return false;
}

void AllowDarkModeForApp(bool allow)
{
	if (_AllowDarkModeForApp)
		_AllowDarkModeForApp(allow);
	else if (_SetPreferredAppMode)
		_SetPreferredAppMode(allow ? AllowDark : Default);
}

void FixDarkScrollBar()
{
	HMODULE hComctl = LoadLibraryExW(L"comctl32.dll", nullptr, LOAD_LIBRARY_SEARCH_SYSTEM32);
	if (hComctl)
	{
		auto addr = FindDelayLoadThunkInModule(hComctl, "uxtheme.dll", 49); // OpenNcThemeData
		if (addr)
		{
			DWORD oldProtect;
			if (VirtualProtect(addr, sizeof(IMAGE_THUNK_DATA), PAGE_READWRITE, &oldProtect))
			{
				auto MyOpenThemeData = [](HWND hWnd, LPCWSTR classList) -> HTHEME {
					if (wcscmp(classList, L"ScrollBar") == 0)
					{
						hWnd = nullptr;
						classList = L"Explorer::ScrollBar";
					}
					return _OpenNcThemeData(hWnd, classList);
				};

				addr->u1.Function = reinterpret_cast<ULONG_PTR>(static_cast<fnOpenNcThemeData>(MyOpenThemeData));
				VirtualProtect(addr, sizeof(IMAGE_THUNK_DATA), oldProtect, &oldProtect);
			}
		}
	}
}

constexpr bool CheckBuildNumber(DWORD buildNumber)
{
	return (buildNumber == 17763 || // 1809
		buildNumber == 18362 || // 1903
		buildNumber == 18363 || // 1909
		buildNumber == 19041 || // 2004
		buildNumber >= 19042); // over 2009
}

void InitDarkMode()
{
	auto RtlGetNtVersionNumbers = reinterpret_cast<fnRtlGetNtVersionNumbers>(GetProcAddress(GetModuleHandleW(L"ntdll.dll"), "RtlGetNtVersionNumbers"));
	if (RtlGetNtVersionNumbers)
	{
		DWORD major, minor;
		RtlGetNtVersionNumbers(&major, &minor, &g_buildNumber);
		g_buildNumber &= ~0xF0000000;
		if (major >= 10 && CheckBuildNumber(g_buildNumber))
		{
			HMODULE hUxtheme = LoadLibraryExW(L"uxtheme.dll", nullptr, LOAD_LIBRARY_SEARCH_SYSTEM32);
			if (hUxtheme)
			{
				_OpenNcThemeData = reinterpret_cast<fnOpenNcThemeData>(GetProcAddress(hUxtheme, MAKEINTRESOURCEA(49)));
				_RefreshImmersiveColorPolicyState = reinterpret_cast<fnRefreshImmersiveColorPolicyState>(GetProcAddress(hUxtheme, MAKEINTRESOURCEA(104)));
				_GetIsImmersiveColorUsingHighContrast = reinterpret_cast<fnGetIsImmersiveColorUsingHighContrast>(GetProcAddress(hUxtheme, MAKEINTRESOURCEA(106)));
				_ShouldAppsUseDarkMode = reinterpret_cast<fnShouldAppsUseDarkMode>(GetProcAddress(hUxtheme, MAKEINTRESOURCEA(132)));
				_AllowDarkModeForWindow = reinterpret_cast<fnAllowDarkModeForWindow>(GetProcAddress(hUxtheme, MAKEINTRESOURCEA(133)));

				auto ord135 = GetProcAddress(hUxtheme, MAKEINTRESOURCEA(135));
				if (g_buildNumber < 18362)
					_AllowDarkModeForApp = reinterpret_cast<fnAllowDarkModeForApp>(ord135);
				else
					_SetPreferredAppMode = reinterpret_cast<fnSetPreferredAppMode>(ord135);

				//_FlushMenuThemes = reinterpret_cast<fnFlushMenuThemes>(GetProcAddress(hUxtheme, MAKEINTRESOURCEA(136)));
				_IsDarkModeAllowedForWindow = reinterpret_cast<fnIsDarkModeAllowedForWindow>(GetProcAddress(hUxtheme, MAKEINTRESOURCEA(137)));

				_SetWindowCompositionAttribute = reinterpret_cast<fnSetWindowCompositionAttribute>(GetProcAddress(GetModuleHandleW(L"user32.dll"), "SetWindowCompositionAttribute"));

				if (_OpenNcThemeData &&
					_RefreshImmersiveColorPolicyState &&
					_ShouldAppsUseDarkMode &&
					_AllowDarkModeForWindow &&
					(_AllowDarkModeForApp || _SetPreferredAppMode) &&
					//_FlushMenuThemes &&
					_IsDarkModeAllowedForWindow)
				{
					g_darkModeSupported = true;

					AllowDarkModeForApp(true);
					_RefreshImmersiveColorPolicyState();

					g_darkModeEnabled = _ShouldAppsUseDarkMode() && !IsHighContrast();

					FixDarkScrollBar();
				}
			}
		}
	}
}

[fafalone]

Yeah that project is where I got the 2nd call from... that's what it's doing in RefreshTitleBarThemeColor. You could try that SetProp call too...

Public Declare Function SetPropW Lib "user32" (ByVal hWnd As Long, ByVal lpString As Long, Optional ByVal hData As Long) As BOOL
Dim bValue As Long: bValue = 1
SetPropW hWnd, StrPtr("UseImmersiveDarkModeColors"), VarPtr(bValue)

It looks like you also need to set the theme to Explorer with SetWindowTheme...
Public Declare Function SetWindowTheme Lib "uxtheme" (ByVal hwnd As Long, ByVal pszSubAppName As Long, ByVal pszSubIdList As Long) As Long
SetWindowTheme hWnd, StrPtr("Explorer"), StrPtr("")

And this thread suggests DWMWA_USE_IMMERSIVE_DARK_MODE should be 19 if your Windows 10 version is earlier than 20H1.


Here's the complete enum, sorry I forgot to include it:

Public Enum WINDOWCOMPOSITIONATTRIB
	WCA_UNDEFINED=0
	WCA_NCRENDERING_ENABLED=1
	WCA_NCRENDERING_POLICY=2
	WCA_TRANSITIONS_FORCEDISABLED=3
	WCA_ALLOW_NCPAINT=4
	WCA_CAPTION_BUTTON_BOUNDS=5
	WCA_NONCLIENT_RTL_LAYOUT=6
	WCA_FORCE_ICONIC_REPRESENTATION=7
	WCA_EXTENDED_FRAME_BOUNDS=8
	WCA_HAS_ICONIC_BITMAP=9
	WCA_THEME_ATTRIBUTES=10
	WCA_NCRENDERING_EXILED=11
	WCA_NCADORNMENTINFO=12
	WCA_EXCLUDED_FROM_LIVEPREVIEW=13
	WCA_VIDEO_OVERLAY_ACTIVE=14
	WCA_FORCE_ACTIVEWINDOW_APPEARANCE=15
	WCA_DISALLOW_PEEK=16
	WCA_CLOAK=17
	WCA_CLOAKED=18
	WCA_ACCENT_POLICY=19
	WCA_FREEZE_REPRESENTATION=20
	WCA_EVER_UNCLOAKED=21
	WCA_VISUAL_OWNER=22
	WCA_HOLOGRAPHIC=23
	WCA_EXCLUDED_FROM_DDA=24
	WCA_PASSIVEUPDATEMODE=25
	WCA_USEDARKMODECOLORS=26
	WCA_CORNER_STYLE=27
	WCA_PART_COLOR=28
	WCA_DISABLE_MOVESIZE_FEEDBACK=29
	WCA_LAST=30
End Enum

As to the entry point, that's weird... it's a documented function Microsoft says appears both in both uxtheme and dwmapi.

[Mith]

Windows 10 Pro 22H2 (19045.2965), Dark Mode enabled

I tried SetWindowTheme+SetPropW and SetPropW alone but still no dark mode for the vb6 window...

I guess we cant just pick some random APIs from the win32-code and get the dark mode for our beloved vb6.
I think without translating the complete win32-code to VB6 it will not work.

Do you know someone can translate the code to VB6?

[fafalone]

It's not picking random APIs it's following the APIs of the examples where others have done this like the two examples linked in this thread. They're both making these same calls. The challenge is to figure out the precise difference that's making it work for them. SetPreferredAppMode perhaps?

It's straightforward enough to translate... you don't need LoadLibrary to get those functions, just use Declare with an alias for the ordinal.

The problematic one is the IAT hook for the scrollbars, you'd need to look at the VB6 examples for that and apply the concept.

[Mith]

i translated the win32-code of the Github Dark Mode project.
I just didn't translate the code for the scrollbars.
Guess what, still no dark mode...

Can you test & review the translation?

Option Explicit

' https://github.com/komiyamma/win32-darkmode/blob/master/win32-darkmode/DarkMode.h

Const WCA_USEDARKMODECOLORS = 26
Const SPI_GETHIGHCONTRAST = 66
Const HCF_HIGHCONTRASTON As Integer = 1

Private Type HIGHCONTRAST
   cbSize As Long
   dwFlags As Long
   lpszDefaultScheme As String
End Type


Private Enum IMMERSIVE_HC_CACHE_MODE
   IHCM_USE_CACHED_VALUE = 0
   IHCM_REFRESH = 1
End Enum

Private Enum PreferredAppMode
   Default = 0
   AllowDark = 1
   ForceDark = 2
   ForceLight = 3
   Max = 4
End Enum

Private Enum WINDOWCOMPOSITIONATTRIB
    WCA_UNDEFINED = 0
    WCA_NCRENDERING_ENABLED = 1
    WCA_NCRENDERING_POLICY = 2
    WCA_TRANSITIONS_FORCEDISABLED = 3
    WCA_ALLOW_NCPAINT = 4
    WCA_CAPTION_BUTTON_BOUNDS = 5
    WCA_NONCLIENT_RTL_LAYOUT = 6
    WCA_FORCE_ICONIC_REPRESENTATION = 7
    WCA_EXTENDED_FRAME_BOUNDS = 8
    WCA_HAS_ICONIC_BITMAP = 9
    WCA_THEME_ATTRIBUTES = 10
    WCA_NCRENDERING_EXILED = 11
    WCA_NCADORNMENTINFO = 12
    WCA_EXCLUDED_FROM_LIVEPREVIEW = 13
    WCA_VIDEO_OVERLAY_ACTIVE = 14
    WCA_FORCE_ACTIVEWINDOW_APPEARANCE = 15
    WCA_DISALLOW_PEEK = 16
    WCA_CLOAK = 17
    WCA_CLOAKED = 18
    WCA_ACCENT_POLICY = 19
    WCA_FREEZE_REPRESENTATION = 20
    WCA_EVER_UNCLOAKED = 21
    WCA_VISUAL_OWNER = 22
    WCA_LAST = 23
End Enum

Private Type WINDOWCOMPOSITIONATTRIBDATA
   Attrib As WINDOWCOMPOSITIONATTRIB
   pvData As Long
   cbData As Long
End Type

Private Declare Sub RtlGetNtVersionNumbers Lib "NTDLL.DLL" (major As Long, minor As Long, Build As Long)

Private Declare Function SetWindowCompositionAttribute Lib "user32" (ByVal HWND As Long, wca As WINDOWCOMPOSITIONATTRIBDATA) As Long

' 1809 17763
Private Declare Function ShouldAppsUseDarkMode Lib "uxtheme.dll" Alias "#132" () As Boolean
Private Declare Function AllowDarkModeForWindow Lib "uxtheme.dll" Alias "#133" (HWND As Long, allow As Boolean) As Boolean
Private Declare Function AllowDarkModeForApp Lib "uxtheme.dll" Alias "#135" (allow As Boolean) As Boolean
Private Declare Function FlushMenuThemes Lib "uxtheme.dll" Alias "#136" ()
Private Declare Function RefreshImmersiveColorPolicyState Lib "uxtheme.dll" Alias "#104" () As Boolean
Private Declare Function IsDarkModeAllowedForWindow Lib "uxtheme.dll" Alias "#137" (HWND As Long) As Boolean
Private Declare Function GetIsImmersiveColorUsingHighContrast Lib "uxtheme.dll" Alias "#106" (mode As IMMERSIVE_HC_CACHE_MODE) As Long
Private Declare Function OpenNcThemeData Lib "uxtheme.dll" Alias "#49" (HWND As Long, pszClassList As Long) As Long

' 1903 18362
Private Declare Function fnShouldSystemUseDarkMode Lib "uxtheme.dll" Alias "#138" () As Boolean
Private Declare Function SetPreferredAppMode Lib "uxtheme.dll" Alias "#135" (appMode As PreferredAppMode) As PreferredAppMode
Private Declare Function IsDarkModeAllowedForApp Lib "uxtheme.dll" Alias "#139" () As Boolean


' others
Private Declare Function SystemParametersInfo Lib "user32" Alias "SystemParametersInfoA" ( _
                                                                                          ByVal uAction As Long, _
                                                                                          ByVal uParam As Long, _
                                                                                          ByRef lpvParam As Any, _
                                                                                          ByVal fuWinIni As Long) As Long

Private Declare Function SetPropW Lib "user32" (ByVal HWND As Long, ByVal lpString As Long, Optional ByVal hData As Long) As Boolean

Public g_darkModeSupported As Boolean
Public g_darkModeEnabled As Boolean
Dim g_buildNumber As Long

Private Function fnAllowDarkModeForWindow(ByRef HWND As Long, ByRef allow As Boolean) As Boolean
'bool AllowDarkModeForWindow(HWND hWnd, bool allow)
'{
'   if (g_darkModeSupported)
'      return _AllowDarkModeForWindow(hWnd, allow);
'   return false;
'}
   If g_darkModeSupported = True Then
      fnAllowDarkModeForWindow = AllowDarkModeForWindow(HWND, allow)
   Else
      fnAllowDarkModeForWindow = False
   End If
End Function

Private Function IsHighContrast() As Boolean
'bool IsHighContrast()
'{
'   HIGHCONTRASTW highContrast = { sizeof(highContrast) };
'   if (SystemParametersInfoW(SPI_GETHIGHCONTRAST, sizeof(highContrast), &highContrast, FALSE))
'      return highContrast.dwFlags & HCF_HIGHCONTRASTON;
'   return false;
'}
   Dim high_Contrast As HIGHCONTRAST
   
   If SystemParametersInfo(SPI_GETHIGHCONTRAST, LenB(high_Contrast), high_Contrast, 0) Then
      IsHighContrast = high_Contrast.dwFlags Or HCF_HIGHCONTRASTON
   Else
      IsHighContrast = False
   End If
End Function

Private Sub RefreshTitleBarThemeColor(ByRef HWND As Long)
'void RefreshTitleBarThemeColor(HWND hWnd)
'{
'   BOOL dark = FALSE;
'   if (_IsDarkModeAllowedForWindow(hWnd) &&
'      _ShouldAppsUseDarkMode() &&
'      !IsHighContrast())
'   {
'      dark = TRUE;
'   }
'   if (g_buildNumber < 18362)
'      SetPropW(hWnd, L"UseImmersiveDarkModeColors", reinterpret_cast<HANDLE>(static_cast<INT_PTR>(dark)));
'   else if (_SetWindowCompositionAttribute)
'   {
'      WINDOWCOMPOSITIONATTRIBDATA data = { WCA_USEDARKMODECOLORS, &dark, sizeof(dark) };
'      _SetWindowCompositionAttribute(hWnd, &data);
'   }
'}
   Dim dark As Boolean
   Dim bPropValue As Long
   Dim bCompValue As Long
   Dim tWCAD As WINDOWCOMPOSITIONATTRIBDATA
   
   dark = False
   bPropValue = 1
   bCompValue = 1
   
   If IsDarkModeAllowedForWindow(HWND) = True And ShouldAppsUseDarkMode = True And IsHighContrast = False Then
      dark = True
   End If
   
   If g_buildNumber < 18362 Then
      Call SetPropW(HWND, StrPtr("UseImmersiveDarkModeColors"), VarPtr(bPropValue))
   Else
      tWCAD.Attrib = WCA_USEDARKMODECOLORS
      tWCAD.pvData = VarPtr(bCompValue)
      tWCAD.cbData = LenB(bCompValue)
      Call SetWindowCompositionAttribute(HWND, tWCAD)
   End If
   
End Sub

Private Function IsColorSchemeChangeMessage(ByRef lParam As String) As Boolean
'bool IsColorSchemeChangeMessage(LPARAM lParam)
'{
'   bool is = false;
'   if (lParam && CompareStringOrdinal(reinterpret_cast<LPCWCH>(lParam), -1, L"ImmersiveColorSet", -1, TRUE) == CSTR_EQUAL)
'   {
'      _RefreshImmersiveColorPolicyState();
'      is = true;
'   }
'   _GetIsImmersiveColorUsingHighContrast(IHCM_REFRESH);
'   return is;
'}
   Dim bIS As Boolean
   
   bIS = False
   
   If Len(lParam) <> 0 Then
      If lParam = "ImmersiveColorSet" Then
         Call RefreshImmersiveColorPolicyState
         bIS = True
      End If
   End If
   Call GetIsImmersiveColorUsingHighContrast(IHCM_REFRESH)
   IsColorSchemeChangeMessage = bIS
   
End Function

'bool IsColorSchemeChangeMessage(UINT message, LPARAM lParam)
'{
'   if (message == WM_SETTINGCHANGE)
'      return IsColorSchemeChangeMessage(lParam);
'   return false;
'}

Private Sub fnAllowDarkModeForApp(allow As Boolean)
'void AllowDarkModeForApp(bool allow)
'{
'   if (_AllowDarkModeForApp)
'      _AllowDarkModeForApp(allow);
'   else if (_SetPreferredAppMode)
'      _SetPreferredAppMode(allow ? AllowDark : Default);
'}
   If g_buildNumber < 18362 Then
      Call AllowDarkModeForApp(allow)
   ElseIf allow = True Then
      Call SetPreferredAppMode(AllowDark)
   Else
      Call SetPreferredAppMode(Default)
   End If
End Sub

Private Function CheckBuildNumber(ByRef buildNumber As Long) As Boolean
'constexpr bool CheckBuildNumber(DWORD buildNumber)
'{
'   return (buildNumber == 17763 || // 1809
'      buildNumber == 18362 || // 1903
'      buildNumber == 18363 || // 1909
'      buildNumber == 19041 || // 2004
'      buildNumber >= 19042); // over 2009
'}
   If buildNumber = 17763 Or buildNumber = 18362 Or buildNumber = 18363 Or buildNumber = 19041 Or buildNumber >= 19042 Then
      CheckBuildNumber = True
   Else
      CheckBuildNumber = False
   End If

End Function

Public Sub InitDarkMode2(ByRef HWND As Long)
   
Debug.Print RefreshImmersiveColorPolicyState
Debug.Print SetPreferredAppMode(ForceDark)
Debug.Print RefreshImmersiveColorPolicyState

End Sub

Public Sub InitDarkMode(ByRef HWND As Long)
   
   Dim major As Long
   Dim minor As Long
   Dim bAllow As Boolean
   
   Call RtlGetNtVersionNumbers(major, minor, g_buildNumber)
   g_buildNumber = g_buildNumber Xor &HF0000000
   
   If major >= 10 And CheckBuildNumber(g_buildNumber) Then
            
            'If OpenNcThemeData And
            If RefreshImmersiveColorPolicyState = True Then
            If ShouldAppsUseDarkMode = True Then
            If AllowDarkModeForWindow(HWND, True) = True Then
               
               If g_buildNumber < 18362 Then
                  Call AllowDarkModeForApp(True)
               Else
                  Call SetPreferredAppMode(ForceDark)
               End If
               
               If IsDarkModeAllowedForWindow(HWND) = True Then
               
                  g_darkModeSupported = True
   
                  Call fnAllowDarkModeForApp(True)
                  Call RefreshImmersiveColorPolicyState
   
                  g_darkModeEnabled = ShouldAppsUseDarkMode() And (IsHighContrast() = False)
   
                  'FixDarkScrollBar();
               End If
            End If
            End If
            End If
   End If

End Sub

[Mith]

I found another example called Enable a Dark mode title bar for Win32 applications from Microsoft, but my translated code still not work with vb6:

C++ code:

#ifndef DWMWA_USE_IMMERSIVE_DARK_MODE
#define DWMWA_USE_IMMERSIVE_DARK_MODE 20
#endif


BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
   hInst = hInstance; // Store instance handle in our global variable

   HWND hWnd = CreateWindowW(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, nullptr, nullptr, hInstance, nullptr);

   BOOL value = TRUE;
   ::DwmSetWindowAttribute(hWnd, DWMWA_USE_IMMERSIVE_DARK_MODE, &value, sizeof(value));

   if (!hWnd)
   {
      return FALSE;
   }

   ShowWindow(hWnd, nCmdShow);
   UpdateWindow(hWnd);

   return TRUE;
}

my VB6 code:

Private Declare Function DwmSetWindowAttribute Lib "dwmapi.dll" (ByVal HWND As Long, ByVal dwAttribute As Long, ByRef pvAttribute As Long, ByVal cbAttribute As Long) As Long
Private Const DWMWA_USE_IMMERSIVE_DARK_MODE = 20

Private Sub Form_Load()

   Dim bValue As Long
   bValue = 1

   Call DwmSetWindowAttribute(Me.hWnd, DWMWA_USE_IMMERSIVE_DARK_MODE, bValue, LenB(bValue))

End Sub

I'm starting to think that Dark Mode isn't possible with VB6...

[fafalone]

Is it working with c++?

[Schmidt]

my VB6 code:

Private Declare Function DwmSetWindowAttribute Lib "dwmapi.dll" (ByVal HWND As Long, ByVal dwAttribute As Long, ByRef pvAttribute As Long, ByVal cbAttribute As Long) As Long
Private Const DWMWA_USE_IMMERSIVE_DARK_MODE = 20

Private Sub Form_Load()

   Dim bValue As Long
   bValue = 1

   Call DwmSetWindowAttribute(Me.hWnd, DWMWA_USE_IMMERSIVE_DARK_MODE, bValue, LenB(bValue))

End Sub

I'm starting to think that Dark Mode isn't possible with VB6...

Works as it should here in my IDE on Win11 (which I have running "manifested, enabling Themes").

I'm quite sure, that all this DWM-stuff only works properly, when you include a proper manifest (either in your compiled Exe, or in the IDE itself).

Olaf

[Mith]

Is it working with c++?

I didnt try, but i think so, because many ppl used this code to get the dark mode title bar.

[Mith]

Works as it should here in my IDE on Win11 (which I have running "manifested, enabling Themes").
I'm quite sure, that all this DWM-stuff only works properly, when you include a proper manifest (either in your compiled Exe, or in the IDE itself).

Im developing with win10 (latest) and i use this manifest file for my VB IDE:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
<assemblyIdentity
    version="1.0.0.0"
    processorArchitecture="X86"
    name="Microsoft.VisualBasic6.IDE"
    type="win32"
/>
<description>Microsoft Visual Basic 6 IDE</description>
<dependency>
    <dependentAssembly>
        <assemblyIdentity
            type="win32"
            name="Microsoft.Windows.Common-Controls"
            version="6.0.0.0"
            processorArchitecture="X86"
            publicKeyToken="6595b64144ccf1df"
            language="*"
        />
    </dependentAssembly>
</dependency>
</assembly>

and i use this manifest file for my dark mode test exe file:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3">
  <assemblyIdentity
    version="1.0.0.0"
    processorArchitecture="*"
    name="win32-darkmode"
    type="win32"
  />
  <dependency>
    <dependentAssembly>
      <assemblyIdentity
        type="win32"
        name="Microsoft.Windows.Common-Controls"
        version="6.0.0.0"
        processorArchitecture="*"
        publicKeyToken="6595b64144ccf1df"
        language="*"
      />
    </dependentAssembly>
  </dependency>
  <compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
    <application>
      <!-- Windows 10 -->
      <supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}"/>
      <!-- Windows 8.1 -->
      <supportedOS Id="{1f676c76-80e1-4239-95bb-83d0f6d0da78}"/>
      <!-- Windows Vista -->
      <supportedOS Id="{e2011457-1546-43c5-a5fe-008deee3d3f0}"/>
      <!-- Windows 7 -->
      <supportedOS Id="{35138b9a-5d96-4fbd-8e2d-a2440225f93a}"/>
      <!-- Windows 8 -->
      <supportedOS Id="{4a2f28e3-53b9-4441-ba9c-d69d4a4a6e38}"/>
    </application>
  </compatibility>
  <asmv3:application>
    <asmv3:windowsSettings xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings">
      <dpiAware>true</dpiAware>
    </asmv3:windowsSettings>
  </asmv3:application>
</assembly>

Any suggestions whats wrong or missing?

[Mith]

It works! I lost the thread from all the testing...i forgot that the color of the windows title bar only changes to dark when i switch to another window!

[Mith]

Summary for Visual Basic 6 Dark Mode for the Form Title Bar & Control Scrollbars:



Notes:

- all controls used on the form above are from Krool's ActiveX CommonControls Replacement
- The Windows Dark Mode must not be active to use the dark mode style
- a vb manifest is not necessary to use the dark mode style
- tested with Win10.0.19045.2965

Conclusion:

It seems like that the button control is the only control that fully support the Dark Mode style.
For all other controls the developer must set the background & fore color by himself.
Unfortunately this is not possible with the OptionButton control and the CheckBox control, because the active visual style doesnt allow to change the forecolor of these controls.
The same applies to the column headers of the list view in report mode, but here you cant change the background color.



Code for the window title bar dark mode:

Private Declare Function DwmSetWindowAttribute Lib "dwmapi.dll" (ByVal HWND As Long, ByVal dwAttribute As Long, ByRef pvAttribute As Long, ByVal cbAttribute As Long) As Long
Private Const DWMWA_USE_IMMERSIVE_DARK_MODE = 20

Private Sub Form_Load()

   Dim bValue As Long
   bValue = 1

   Call DwmSetWindowAttribute(Me.hWnd, DWMWA_USE_IMMERSIVE_DARK_MODE, bValue, LenB(bValue))

End Sub

Code for the control scrollbar dark mode:

Private Declare Function SetWindowTheme Lib "uxtheme" (ByVal hwnd As Long, ByVal pszSubAppName As Long, ByVal pszSubIdList As Long) As Long
Private Sub Form_Load()
 SetWindowTheme control.hwnd, StrPtr("DarkMode_Explorer"), 0&
End Sub

[wqweto]

https://github.com/nptr/msstyleEditor

You can open C:\Windows\Resources\Themes\aero\aero.msstyles and notice there are a lot of "DarkMode_Xxx" classes e.g. there is "DarkMode_CFD:ComboBox" on my Win11.

Try using SetWindowTheme combobox.hWnd, StrPtr("CFD") for ComboBoxes and probably a separate call for the dropdown scollbars will be needed.

cheers,
</wqw>

[Mith]

Try using SetWindowTheme combobox.hWnd, StrPtr("CFD") for ComboBoxes and probably a separate call for the dropdown scollbars will be needed.

Thank you for the feedback. I tried StrPtr("CFD") with the ComboBox but no effect on the colors.

[wqweto]

You tried CFD but didn't try DarkMode_CFD and DarkMode_CFD:ComboBox? This is not how green-field research is done. . .

Did you download the tool to peak at other classes available?

cheers,
</wqw>

[Mith]

You tried CFD but didn't try DarkMode_CFD and DarkMode_CFD:ComboBox? This is not how green-field research is done.

Yes, you are right. DarkMode_CFD changes the combobox to Dark Mode. Today i will download the tool and look for other style classes.

After and before:



Combobox Dropdown Menu:



My current Dark Mode progress:



I used the backcolor and forecolor properties to set the dark mode color for all controls and the form.

Unsolved problems so far:

- the toolbar draws a light line on the top
- cant change the listview column headers color (this can be solved by disabling the theme style for the headers and subclassing)
- cant change the option button forecolor
- cant change the checkbox forecolor
- white background color at the HScroll/VScroll control
- cant change the statusbar backcolor

all controls are from Krools MS Common Controls Replacement.

[Mith]

Did you download the tool to peak at other classes available?

I downloaded the code but i cant run/compile the code. I found this on the internet:

<!-- Windows 10 Dark Mode > Toolbars, Headers, & Rebar -->
		<class name="DarkModeNavbarComposited::Rebar"/>
		<class name="DarkModeInactiveNavbarComposited::Rebar"/>
		<class name="DarkModeMaxNavbarComposited::Rebar"/>
		<class name="DarkModeMaxInactiveNavbarComposited::Rebar"/>
		<class name="DarkModeNavbarBase::Rebar"/>
		<class name="DarkModeNavbarNonTopmost::Rebar"/>
		<class name="DarkModeNavbar::Rebar"/>
		<class name="DarkModeInactiveNavbar::Rebar"/>
		<class name="DarkModeMaxNavbar::Rebar"/>
		<class name="DarkModeMaxInactiveNavbar::Rebar"/>
		<class name="DarkMode::Toolbar"/>
		<class name="DarkMode_ItemsView::Header"/>
	<!-- Windows 10 Dark Mode > Address, Breadcrumb, & Search -->
		<class name="DarkMode_ABComposited::AddressBand"/>
		<class name="DarkMode_AddressComposited::ComboBox"/>
		<class name="DarkMode_InactiveAddressComposited::ComboBox"/>
		<class name="DarkMode_MaxAddressComposited::ComboBox"/>
		<class name="DarkMode_MaxInactiveAddressComposited::ComboBox"/>
		<class name="DarkMode_AddressComposited::Edit"/>
		<class name="DarkMode_InactiveAddressComposited::Edit"/>
		<class name="DarkMode_MaxAddressComposited::Edit"/>
		<class name="DarkMode_MaxInactiveAddressComposited::Edit"/>
		<class name="DarkMode_BBComposited::Toolbar"/>
		<class name="DarkMode_InactiveBBComposited::Toolbar"/>
		<class name="DarkMode_MaxBBComposited::Toolbar"/>
		<class name="DarkMode_MaxInactiveBBComposited::Toolbar"/>
		<class name="DarkMode::TryHarder"/>
		<class name="DarkMode_SearchBoxEditComposited::Edit"/>
		<class name="DarkMode_InactiveSearchBoxEditComposited::Edit"/>
		<class name="DarkMode_MaxSearchBoxEditComposited::Edit"/>
		<class name="DarkMode_MaxInactiveSearchBoxEditComposited::Edit"/>
		<class name="DarkMode_SearchBoxComposited::SearchBox"/>
		<class name="DarkMode_InactiveSearchBoxComposited::SearchBox"/>
		<class name="DarkMode_MaxSearchBoxComposited::SearchBox"/>
		<class name="DarkMode_MaxInactiveSearchBoxComposited::SearchBox"/>
		<class name="DarkMode::SearchBox"/>
	<!-- Windows 10 Dark Mode > Buttons, Boxes, & Controls -->
		<class name="Explorer::Button"/>
		<class name="DarkMode_Explorer::Button"/>
		<class name="DarkMode::Navigation"/>
		<class name="CFD::Combobox"/>
		<class name="DarkMode_CFD::Combobox"/>
		<class name="Explorer::ScrollBar"/>
		<class name="DarkMode_Explorer::ScrollBar"/>
	<!-- Windows 10 Dark Mode > Lists, Menus, & Tabs -->
		<class name="DarkMode::Menu"/>
		<class name="DarkMode_ImmersiveStart::Menu"/>
	<!-- Windows 10 Dark Mode > Explorer & Shell -->
		<class name="DarkMode_Explorer::TreeView"/>
		<class name="DarkMode::CommandModule"/>
		<class name="Explorer::CommandModule"/>
		<class name="DarkMode_Explorer::CommandModule"/>
		<class name="DarkMode_Explorer::Tooltip"/>
		<class name="DarkMode::ReadingPane"/>
		<class name="DarkMode::PreviewPane"/>
		<class name="DarkMode::ProperTree"/>
		<class name="ExplorerNavPane"/>
		<class name="DarkMode::ExplorerNavPane"/>
		<class name="DarkMode::ItemsView"/>
		<class name="DarkMode_CFD::Edit"/>
		<class name="DarkMode_Explorer::Edit"/>
		<class name="DarkMode_ItemsView::ListView"/>
		<class name="ExplorerStatusBar"/>
		<class name="DarkMode::ExplorerStatusBar"/>
		<class name="DarkMode_InfoPaneToolbar::Toolbar"/>
		<class name="CommonItemsDialog"/>
		<class name="DarkMode::CommonItemsDialog"/>
	</add>

[Mith]

The dark mode for the ListView column headers can be activated using the following code:

SetWindowTheme ListView1.hWndHeader, StrPtr("DarkMode_ItemsView"), 0&

[fafalone]

I'm curious about this comment of yours:

- The Windows Dark Mode must not be active to use the dark mode style

So the rest of the system will have to be in light mode in order for your application to be in dark mode?

[wqweto]

I downloaded the code but i cant run/compile the code.

There is compiled EXE under Releases link -- on repo's home page in the right column there is About section, then Releases section where it says "+27 releases".

cheers,
</wqw>

[Mith]

So the rest of the system will have to be in light mode in order for your application to be in dark mode?

No, it doesnt matter if the Windows Dark Mode is active or not to use the Dark Mode with a VB6 app!

[Mith]

There is compiled EXE under Releases link -- on repo's home page in the right column there is About section, then Releases section where it says "+27 releases".

Got the exe and the list:

[fafalone]

How did you get the scroll bars fixed? I saw some IAT hooking in the original but not the snippet you posted.

[Mith]

How did you get the scroll bars fixed? I saw some IAT hooking in the original but not the snippet you posted.

You will get dark scrollbars with this API call:

SetWindowTheme control.hwnd, StrPtr("DarkMode_Explorer"), 0&

[wqweto]

@Mith: Can you post code of your research project where you took the final screenshot above from, please?

Did you set form's BackColor manually and what color did you use for this? RGB(25, 25, 25)?

cheers,
</wqw>

[Mith]

@Mith: Can you post code of your research project where you took the final screenshot above from, please?

Unfortunately, I no longer have the program code from the time of the screenshot. The current program code uses various other external libraries for testing purposes, and it wouldn't run on your system. What information exactly do you need?

Did you set form's BackColor manually and what color did you use for this? RGB(25, 25, 25)?

Me.BackColor = 4013373

[wqweto]

hex(4013373) = &H3D3D3D

. . . which is some sort of darker grey.

Is this TextBox background color or Form's one?

cheers,
</wqw>

[Mith]

Is this TextBox background color or Form's one?

I use this color for the backcolor of all forms & controls.

[wqweto]

I use this color for the backcolor of all forms & controls.

I see. Interesting -- Form's backcolor is lighter grey than TextBox and ComboBox backgrounds. .

Btw, these colors can be derived from certain theme parts i.e. using msstyleEditor one can explore where these backcolors are located for darkmode "application names" (the pszSubAppName param).

cheers,
</wqw>