diff --git a/Polyhedron/demo/Polyhedron/MainWindow.cpp b/Polyhedron/demo/Polyhedron/MainWindow.cpp
index 43aaefc1c9f..aaed60eca86 100644
--- a/Polyhedron/demo/Polyhedron/MainWindow.cpp
+++ b/Polyhedron/demo/Polyhedron/MainWindow.cpp
@@ -17,6 +17,7 @@
 #include <QMenuBar>
 #include <QChar>
 #include <QAction>
+#include <QWidgetAction>
 #include <QShortcut>
 #include <QKeySequence>
 #include <QLibrary>