#include <TGClient.h>
#include <TGButton.h>
#include <TGFrame.h>
ROOT::RDataFrame *dfRaw;

class MyMainFrame : public TGMainFrame {
 
private:
   TGCompositeFrame *fCframe;
   TGTextButton     *fStart, *fPause, *fExit;
   Bool_t            start, pause;
 
public:
   MyMainFrame(const TGWindow *p, UInt_t w, UInt_t h);
   ~MyMainFrame() override;
   // slots
   void ChangeStartLabel();
   void ChangePauseLabel();
 
   ClassDef(MyMainFrame, 0)
};
 
void MyMainFrame::ChangeStartLabel()
{
  // Slot connected to the Clicked() signal.
  // It will toggle labels "Start" and "Stop".
 
  fStart->SetState(kButtonDown);
  if (!start) {
     fStart->SetText("&Stop");
     start = kTRUE;
  } else {
     fStart->SetText("&Start");
     start = kFALSE;
  }
  fStart->SetState(kButtonUp);
  cout <<": " <<  dfRaw->Mean("column1").GetValue() << endl;

}
 
void MyMainFrame::ChangePauseLabel()
{
  // Slot connected to the Clicked() signal.
  // It will toggle labels "Resume" and "Pause".
 
  fPause->SetState(kButtonDown);
  if (!pause) {
     fPause->SetText("&Resume");
     pause = kTRUE;
  } else {
     fPause->SetText("&Pause");
     pause = kFALSE;
  }
  fPause->SetState(kButtonUp);
}
 
MyMainFrame::MyMainFrame(const TGWindow *p, UInt_t w, UInt_t h) :
  TGMainFrame(p, w, h)
{
   // Create a horizontal frame containing buttons
   fCframe = new TGCompositeFrame(this, 170, 20, kHorizontalFrame|kFixedWidth);
 
   fStart = new TGTextButton(fCframe, "&Start");
   fStart->Connect("Clicked()", "MyMainFrame", this, "ChangeStartLabel()");
   fCframe->AddFrame(fStart, new TGLayoutHints(kLHintsTop | kLHintsExpandX,
                                               3, 2, 2, 2));
   fStart->SetToolTipText("Click to toggle the button label (Start/Stop)");
   start = kFALSE;
 
   fPause = new TGTextButton(fCframe, "&Pause");
   fPause->Connect("Clicked()", "MyMainFrame", this, "ChangePauseLabel()");
   fPause->SetToolTipText("Click to toggle the button label (Pause/Resume)");
   fCframe->AddFrame(fPause, new TGLayoutHints(kLHintsTop | kLHintsExpandX,
                                               3, 2, 2, 2));
   pause = kFALSE;
 
   AddFrame(fCframe, new TGLayoutHints(kLHintsCenterX, 2, 2, 5, 1));
 
   fExit = new TGTextButton(this, "&Exit ","gApplication->Terminate(0)");
   AddFrame(fExit, new TGLayoutHints(kLHintsTop | kLHintsExpandX,5,5,2,2));
 
   SetWindowName("Change Labels");
 
   MapSubwindows();
   Resize(GetDefaultSize());
   MapWindow();
}
 
 
MyMainFrame::~MyMainFrame()
{
   // Clean up all widgets, frames and layouthints that were used
   fCframe->Cleanup();
   Cleanup();
}
 
 using namespace ROOT;
 
void buttonChangelabel()
{
   ROOT::EnableImplicitMT(2);
   // Popup the GUI...
   new MyMainFrame(gClient->GetRoot(), 350, 80);

   dfRaw = new ROOT::RDataFrame("ttree","PATH_TO_DF.root");
   cout <<": " <<  dfRaw->Mean("column1").GetValue() << endl;

}