Fix Qt scrollbar grippers 1.0

mods/fix-qt-scrollbar-grippers.wh.cpp

@@ -0,0 +1,87 @@
+// ==WindhawkMod==
+// @id              fix-qt-scrollbar-grippers
+// @name            Fix Qt scrollbar grippers
+// @description     Fixes scrollbar grippers in Qt 6.1+
+// @version         1.0
+// @author          kawapure
+// @github          https://github.com/kawapure
+// @twitter         https://twitter.com/kawaipure
+// @homepage        https://kawapure.github.io
+// @include         ida64.exe
+// @compilerOptions -lcomdlg32 -luxtheme
+// ==/WindhawkMod==
+
+// ==WindhawkModReadme==
+/*
+# Fix Qt scrollbar grippers
+
+![Preview](https://raw.githubusercontent.com/kawapure/images/main/fix-qt-scrollbar-grippers.png)
+
+Qt applications compiled after 2021 (against Qt 6.1+) lack the scrollbar grippers (the lines in the middle),
+visible on custom visual styles, because the responsible drawing code was removed. Here is a lazy hack around
+that.
+
+These were removed in Qt [because the developers thought that these changes wouldn't affect Windows 10](https://github.com/qt/qtbase/commit/5f5c342924a0d9a2856b2f2d6db373e25723f2b0).
+They were wrong.
+*/
+// ==/WindhawkModReadme==
+
+#include <windhawk_api.h>
+#include <windhawk_utils.h>
+#include <uxtheme.h>
+#include <vsstyle.h>
+
+using DrawThemeBackgroundEx_t = decltype(&DrawThemeBackgroundEx);
+DrawThemeBackgroundEx_t DrawThemeBackgroundEx_orig;
+HRESULT WINAPI DrawThemeBackgroundEx_hook(HTHEME hTheme, HDC hdc, int iPartId, int iStateId, LPCRECT pRect, const DTBGOPTS *pOptions)
+{
+    HRESULT result = DrawThemeBackgroundEx_orig(hTheme, hdc, iPartId, iStateId, pRect, pOptions);
+
+    if (iPartId == SBP_THUMBBTNHORZ || iPartId == SBP_THUMBBTNVERT)
+    {
+        if (iPartId == SBP_THUMBBTNHORZ)
+            Wh_Log(L"dtb: is SBP_THUMBBTNHORZ");
+        else if (iPartId == SBP_THUMBBTNVERT)
+            Wh_Log(L"dtb: is SBP_THUMBBTNVERT");
+
+        int gripperPart = iPartId == SBP_THUMBBTNHORZ
+                ? SBP_GRIPPERHORZ
+                : SBP_GRIPPERVERT;
+
+        SIZE gripperSize = { 0 };
+        GetThemePartSize(hTheme, hdc, gripperPart, iStateId, nullptr, TS_TRUE, &gripperSize);
+
+        if (
+            (iPartId == SBP_THUMBBTNVERT && (pRect->bottom - pRect->top) > gripperSize.cy) ||
+            (iPartId == SBP_THUMBBTNHORZ && (pRect->right - pRect->left) > gripperSize.cx)
+        )
+        {
+            Wh_Log(L"drawing gripper");
+
+            DrawThemeBackground(hTheme, hdc, gripperPart, iStateId, pRect, nullptr);
+        }
+    }
+
+    return result;
+}
+
+// The mod is being initialized, load settings, hook functions, and do other
+// initialization stuff if required.
+BOOL Wh_ModInit()
+{
+    Wh_Log(L"Init");
+
+    Wh_SetFunctionHook(
+        (void *)DrawThemeBackgroundEx,
+        (void *)DrawThemeBackgroundEx_hook,
+        (void **)&DrawThemeBackgroundEx_orig
+    );
+
+    return TRUE;
+}
+
+// The mod is being unloaded, free all allocated resources.
+void Wh_ModUninit()
+{
+    Wh_Log(L"Uninit");
+}