title: How can I resize QMessageBox?
body: <p>I have a <code>QMessageBox</code> which I'd like it to be bigger. It's a simple <code>QMessageBox</code> with two standard buttons, Ok and Cancel. The problem is that it is very small for my application's purposes. Code shows like this:</p>
  
  <pre><code>QMessageBox msg;
  msg.setText("Whatever");
  msg.setStandardButtons(QMessageBox::Ok | QMessageBox::Cancel);
  msg.setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);
  
  int ret = msg.exec();
  switch (ret) {
    case QMessageBox::Ok:
        ui-&gt;textEdit-&gt;clear();
        break;
    case QMessageBox::Cancel:
        break;}
  </code></pre>
  
  <p>I tried several ways to increase the size:</p>
  
  <pre><code>msg.setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);
  
  msg.setSizePolicy(QSizePolicy::Maximum,QSizePolicy::Maximum);
  
  msg.setFixedHeight(600);
  msg.setFixedWidth(600);
  </code></pre>
  
  <p>I even cleared and rebuilt, and it compiles everything but nothing take effect...</p>
  
  <p>Do you have any idea on how to set QMessageBox size "by hand"? Thanks.</p>