Painting a TCanvas to the screen in a compiled ROOT (CERN) application

Question

What are the rules for painting to the screen?

My end goal is to put the TCanvas into a class and paint from there, but for now I think that maybe looking at a less

Answer 1

I usually use TApplications like below to have TCanvases really appear as window on the screen.

#include "TApplication.h"
// other stuff

int main(int argc, char** argv) {
  TApplication theApp("App",&argc, argv);
  // your code
  // here you can Draw() things
  theApp.Run();
  return 0;
}

The program then just stops at Run() and I end the process with ^C.