diff -r a730825bc5e4 -r d03a426e0b6b src/ChartCarbonate.h
--- a/src/ChartCarbonate.h	Tue Jul 26 11:15:37 2022 +0200
+++ b/src/ChartCarbonate.h	Tue Jul 26 14:26:50 2022 +0200
@@ -1,9 +1,12 @@
 #ifndef _CHARTCARBONATE_H
 #define _CHARTCARBONATE_H
 
+#include "MainWindow.h"
+
 #include <QDialog>
 #include <QDialogButtonBox>
 
+class Callout;
 
 namespace Ui {
 class ChartCarbonate;
@@ -13,10 +16,21 @@
 {
     Q_OBJECT
 
+private slots:
+    void savePNG();
+
+public slots:
+    void tooltip(QPointF point, bool state);
+
 public:
     explicit ChartCarbonate(QString code, QString name, QWidget *parent = 0);
     ~ChartCarbonate();
 
+private:
+    QChartView *chartView;
+    QChart *chart;
+    Callout *t_tooltip = 0;
+    QSplineSeries *temperature, *pressure;
 };
 
 #endif