update

src/FluFramelessHelper.cpp

@@ -165,16 +165,23 @@ bool FramelessEventFilter::nativeEventFilter(const QByteArray &eventType, void *
     }else if(uMsg == WM_NCACTIVATE){
         *result = ::DefWindowProcW(hwnd, WM_NCACTIVATE, wParam, -1);
         return true;
-    }else if(uMsg == WM_GETMINMAXINFO && QT_VERSION < QT_VERSION_CHECK(6,0,0)){
+    }else if(uMsg == WM_GETMINMAXINFO){
         MINMAXINFO* minmaxInfo = reinterpret_cast<MINMAXINFO *>(lParam);
+#if QT_VERSION >= QT_VERSION_CHECK(6,0,0)
+        minmaxInfo->ptMaxPosition.x = 0;
+        minmaxInfo->ptMaxPosition.y = 0;
+        minmaxInfo->ptMaxSize.x = 0;
+        minmaxInfo->ptMaxSize.y = 0;
+#else
+        auto pixelRatio = _helper->window->devicePixelRatio();
+        auto geometry = _helper->window->screen()->availableGeometry();
         RECT rect;
         SystemParametersInfo(SPI_GETWORKAREA, 0, &rect, 0);
-        int cx = rect.right - rect.left + offsetXY.x()*2;
-        int cy = rect.bottom - rect.top + offsetXY.y()*2;
         minmaxInfo->ptMaxPosition.x = rect.left - offsetXY.x();
         minmaxInfo->ptMaxPosition.y = rect.top - offsetXY.x();
-        minmaxInfo->ptMaxSize.x = cx;
+        minmaxInfo->ptMaxSize.x = geometry.width()*pixelRatio + offsetXY.x() * 2;
-        minmaxInfo->ptMaxSize.y = cy;
+        minmaxInfo->ptMaxSize.y = geometry.height()*pixelRatio + offsetXY.y() * 2;
+#endif
     }else if(uMsg == WM_NCRBUTTONDOWN){
         if (wParam == HTCAPTION) {
             _helper->showSystemMenu(QCursor::pos());