RE: setting pad properties

Hi Roger,

Why not just using:

      pad = (TPad*)canv->cd(k+1);

instead of:

      canv->cd(k+1);
      sprintf(padname,"canv_%i",k+1);
      pad = (TPad*)(canv->GetPrimitive(padname));

Cheers,
Bertrand.

-----Original Message-----
From: owner-roottalk_at_root.cern.ch [mailto:owner-roottalk_at_root.cern.ch] On Behalf Of Roger Mason
Sent: 04 November 2008 15:15
To: roottalk_at_lxbuild091.cern.ch
Subject: [ROOT] setting pad properties

Hello,

The following code compiles but segfaults at the marked lines. It runs fine if the lines are commented.

#include "TObjArray.h"
#include "TCanvas.h"
#include "TPad.h"

void testpad() {
  TObjArray CanvArray;
  TCanvas* canv;
  TPad* pad;
  char canvname[150];
  char padname[10];

  for ( Int_t i = 0; i < 6; i++ ) { // Loop over unique energies. 1 canvas per energy.

    sprintf(canvname,"Energy_%i",i);
    CanvArray.Add( new TCanvas(canvname,canvname) );     canv = dynamic_cast<TCanvas*>(CanvArray[i]);     canv->Divide(3,3);

    for (Int_t k = 0; k < 9; k++) { // Loop over pads (9 kinds of histo).

      canv->cd(k+1);

      sprintf(padname,"canv_%i",k+1);
      pad = (TPad*)(canv->GetPrimitive(padname));

      pad->SetBorderSize(1); // causes segfault
      //      pad->SetFillColor(33); // causes segfault

      // Draw something on each pad.

    }//Loop over pads
  }// Loop over energies
}

I assume that there is something wrong with the way I'm setting the pointer pad.

Thanks for any help.

Roger Received on Tue Nov 04 2008 - 15:43:38 CET