title: How to set a QVariant structure?
body: <p>I have a <code>QList</code> structure containing a <code>QVariant</code>:</p>
  <pre><code>typedef struct EXTRA_PARAMS_DEF {
      QString name;
      QVariant val;
      int channel;
  } EXTRA_PARAMS;
  QList&lt;EXTRA_PARAMS&gt; EP;
  </code></pre>
  <p>Why I cannot set this <code>QVariant</code> with this function?</p>
  <pre><code>int setParam(QVariant value)
  {
      for (int i=0; i&lt;EP.count(); i++)
      {
          EP.at(i).val = value;
      }
  }
  </code></pre>
  <p>The error is:</p>
  <blockquote>
  <p>error: C2678: '=' binary ': no operator found, accepting a left part</p>
  <p>operation of type' const QVariant ' There is no acceptable conversion</p>
  </blockquote>
  <p>How can I do to set this <code>QVariant</code>? Thanks for ideas.</p>