How to call secondary window from MainWindow class function

[JacobNovitsky]

void MainWindow::on_pushButton_clicked()
{
QuickPaste quickpaste;
quickpaste.show();
}

code above would only work If I call a.exec for QApplication a(argc, argv) right after quickpaste.show();

how do you guys manage this?

I could imagine:
pass QApplication a as an argument
make it global
use some C++ class features

[mpergand]

@JacobNovitsky

void MainWindow::on_pushButton_clicked()
{
    QuickPaste* quickpaste=new QuickPaste();
    quickPaste->setAttribute(Qt::WA_DeleteOnClose);
    quickpaste->show();
}