improve dark mode on win

Zhao Yuhang

2023-12-22 e331fb1feda8891baba2a2dc1caeed67834d9d93

 src/core/contexts/win32windowcontext.cpp

@@ -725,7 +725,7 @@
#if !QWINDOWKIT_CONFIG(ENABLE_WINDOWS_SYSTEM_BORDER)
        {
            auto style = ::GetWindowLongPtrW(hWnd, GWL_STYLE);
            ::SetWindowLongPtrW(hWnd, GWL_STYLE, style | WS_THICKFRAME | WS_CAPTION);
            ::SetWindowLongPtrW(hWnd, GWL_STYLE, (style | WS_THICKFRAME) & (~WS_CAPTION));
        }
#endif

@@ -937,18 +937,24 @@
            if (!isWin101809OrGreater()) {
                return false;
            }

            BOOL enable = attribute.toBool();

            if (isWin101903OrGreater()) {
                apis.pSetPreferredAppMode(enable ? PAM_AUTO : PAM_DEFAULT);
            } else {
                apis.pAllowDarkModeForApp(enable);
            }

            for (const auto attr : {
                    _DWMWA_USE_IMMERSIVE_DARK_MODE_BEFORE_20H1,
                    _DWMWA_USE_IMMERSIVE_DARK_MODE,
            }) {
                apis.pDwmSetWindowAttribute(hwnd, attr, &enable, sizeof(enable));
            }
            WINDOWCOMPOSITIONATTRIBDATA wcad{};
            wcad.Attrib = WCA_USEDARKMODECOLORS;
            wcad.pvData = &enable;
            wcad.cbData = sizeof(enable);
            apis.pSetWindowCompositionAttribute(hwnd, &wcad);

            apis.pFlushMenuThemes();

            return true;
        }
        return false;