Take screenshot of open windows

ROOT
1

On my application, I have several windows with canvases, which I organize on my screen. I then save all the canvases to a TFile and close my application.

When I want to analyse the saved results, I open the TFile with a TBrowser, and double-click on all the canvases to “restore” the original view. This can be tedious if you have 60 independent canvases.

My question:

  • Is it possible to reopen via the TBrowser all the canvases at once?
  • If not, is it possible to tell Root to save a screenshot of the monitor and save it to the TFile? Something like: “bring all my windows to the front if some of them is hidden and save the screenshot to the TFile”.

Thank you in advance.

2

Hi,

[quote=“ferhue”]- Is it possible to reopen via the TBrowser all the canvases at once?[/quote]No, this is not possible.

[quote=“ferhue”]- If not, is it possible to tell Root to save a screenshot of the monitor and save it to the TFile? Something like: “bring all my windows to the front if some of them is hidden and save the screenshot to the TFile”.[/quote]This is not possible either, but why not creating a ROOT macro to achieve what you want (reading and displaying all the canvases saved in the file)?

Cheers, Bertrand.

3

Thank you for the advice.

Here my macro for reopening the canvases, just in case someone finds it also useful.

#include "TCanvas.h"
#include "TROOT.h"
#include "TFile.h"
#include "TString.h"
#include "TKey.h"
#include <iostream>

void test_macro()
{
	//Gets the current file, assuming you have opened it via a TBrowser just before.
	TFile* aFile = gROOT->GetFile();
	//Alternatively:
	//~ TFile* aFile = TFile::Open("someFile.root");
	
	TIter next(aFile->GetListOfKeys());
	TKey *key;
	TCanvas* c;

	while ((key=(TKey*)next())) {
		if(strcmp(key->GetClassName(),"TCanvas")==0)
		{
			c = ((TCanvas*)key->ReadObj());
			c->Draw();
			//Alternatively:
			//~ c->DrawClonePad();
		}
	}
}

The trick now is to save the code above in a file called e.g. test_macro.cpp, and save it in our TFile as a TMacro. Then just by double-clicking on it in the TBrowser, all canvases present inside the TFile will be reopened. Example of how to save the TMacro to our TFile:

#include "TFile.h"
#include "TCanvas.h"
#include "TMacro.h"


// Here, we write to a TFile the TMacro object which opens all canvases at once.
// When opening the TFile via the TBrowser, just by double-clicking on the TMacro, it gets executed and all canvases will be shown.
void test_openAll()
{
	TFile* aFile = new TFile("/tmp/test_openAll.root","RECREATE");
	aFile->cd();
	
	TCanvas* c = new TCanvas("c1","c1");
	c->cd();
	c->Write();
	
	TCanvas* c2 = new TCanvas("c2","c2");
	c2->cd();
	c2->Write();
	
	
	TMacro* ma = new TMacro("test_macro.cpp","VIEW");
	ma->Write();
	
	aFile->Write();
	aFile->Close();
	delete aFile;
}