title: Qt get children from layout
body: <p>I try to hide all widgets in layout. But looks like <code>findChildren</code> doesn't 
  work for layout.</p>
  
  <p>Here's my sample code:</p>
  
  <pre><code>QLayout * layout = widget -&gt; findChild&lt;QLayout *&gt; (layoutName);
  QList&lt;QWidget *&gt; list = layout -&gt; findChildren&lt;QWidget *&gt; ();
  
  cout &lt;&lt; list.size() &lt;&lt; endl;
  </code></pre>
  
  <p><code>size</code> is 0, but inside this layout I have a few widgets.
  But the same code works fine if I try to get widgets from parent widget.</p>
  
  <p>How I can get them from appropriate layout?</p>