title: Qt tr for internationalisation does not work in main function?
body: <p>Qt's translation function <code>tr</code> does not work in the <code>main</code> function but works fine in a QWidget member function. Why is that?</p>
  
  <pre><code>int main(int argc, char *argv[])
  {
  
      QApplication a(argc, argv);
      QDialog dialog; 
      QString temp = tr("dadasda");//error:tr was not declared in this scope
      dialog.show();
      return a.exec();
  }
  </code></pre>