diff -r ac70c7af6a9b -r b13e7ed9eea3 src/RelpipeChartMainWindow.h
--- a/src/RelpipeChartMainWindow.h	Sun Sep 30 18:34:34 2018 +0200
+++ b/src/RelpipeChartMainWindow.h	Sun Sep 30 20:54:35 2018 +0200
@@ -13,15 +13,15 @@
 using namespace relpipe::reader;
 using namespace relpipe::reader::handlers;
 
-class RelpipeChartMainWindow : public QMainWindow, public RelationalReaderStringHadler {
+class RelpipeChartMainWindow : public QMainWindow {
 	Q_OBJECT
 public:
 	RelpipeChartMainWindow();
 	virtual ~RelpipeChartMainWindow();
-	virtual void startRelation(string_t name, std::vector<AttributeMetadata> attributes) override;
-	virtual void attribute(const string_t& value) override;
-	virtual void endOfPipe() override;
 public slots:
+	void startRelation(const string_t name, std::vector<AttributeMetadata> attributes);
+	void attribute(const string_t value);
+	void endOfPipe();
 	void setStatusMessage(string_t message);
 private:
 	Ui::RelpipeChartMainWindow widget;