C/C++ :: How To Reuse Existing Code To Read Data File In Qt

I've got some code in C++ that does some basic analysis on price data and I run it from the cmd prompt. One of the functions I had built to read in the data is as follows:

void ReadPricesFromFile(constchar*filename,std::vector<PriceInfo>&prices)
{std::ifstreaminput(filename);
input>>prices;}

How would one merge this type of code into a Qt GUI? Ideally, I'd like to use something like QFileDialog to open up a folder with my data files, select a file, and then read the file that the user selects. Would the main.cpp look something like this?

int main (int argc, char *argv []) {
QApplication prog (argc, argv);
QPushButton *load_button = new QPushbutton ("Load File");
QObject:: connect (load_button, SIGNAL (clicked()), &prog, SLOT ( (ReadPricesfromFile function?);
load_button-> show ();
return prog.exec ();}