diff --git a/mainwindow.h b/mainwindow.h
--- a/mainwindow.h
+++ b/mainwindow.h
@@ -29,6 +29,7 @@
 #include <QSignalMapper>
 #include <QTimer>
 #include <QColor>
+#include <QtGlobal>
 #include <qwt_plot_curve.h>
 
 #include "portcontrol.h"
@@ -46,6 +47,9 @@ public:
     explicit MainWindow(QWidget *parent = 0);
     ~MainWindow();
 
+    void messageHandler(QtMsgType type, const QMessageLogContext &context,
+                        const QString &msg);
+
 private:
     enum NumberFormat
     {