title: How do I style a Qt Widget not its children with stylesheets?
body: <p>I have a: </p>
  
  <pre><code>class Box : public QWidget
  </code></pre>
  
  <p>and it has </p>
  
  <pre><code>this-&gt;setLayout(new QGridLayout(this));
  </code></pre>
  
  <p>I tried doing: </p>
  
  <pre><code>this-&gt;setStyleSheet( "border-radius: 5px; "
                       "border: 1px solid black;"
                       "border: 2px groove gray;"
                       "background-color:blue;");
  
  this-&gt;setStyleSheet( "QGridLayout{"
                           "background-color:blue;"
                           "border-radius: 5px; "
                           "border: 1px solid black;"
                           "border: 2px groove gray;"
                       "}"
                     );
  
  this-&gt;setObjectName(QString("Box"));
  this-&gt;setStyleSheet( "QWidget#Box {"
                           "background-color:blue;"
                           "border-radius: 5px; "
                           "border: 1px solid black;"
                           "border: 2px groove gray;"
                       "}"
                     );
  </code></pre>
  
  <p>but the first affects only the items that are added, the other two do nothing. I want the box itself to have rounded corners and a border (bonus for how to do lines between rows).</p>
  
  <p>How do I get the stylesheet to affect the Box widget, not its children?</p>