title: How to make use of the private Qt C++ API?
body: <p>I'm trying to use the <code>QBalloonTip</code> class to generate a stilized tooltip for a button with QT 5.8.0.</p>
  
  <p>What I've tried until now is modify the header file <code>qsystemtrayicon_p.h</code> the method <code>QBalloonTip::showBalloon(...)</code> by giving default arguments. However even when I included the header <code>qsystemtrayicon_p.h</code> in my code, I'm having problems when linking the compiled sourced code. Next error appears:</p>
  
  <p><code>LNK2019: unresolved external symbol: "public static void QBalloonTip::showBalloon(...)"</code></p>
  
  <p>Hope anyone has faced this before. Thank you in advance.</p>