title: Hide QStandardItemModel row in data member function
body: <p>How can I hide / exclude entire rows from a <code>QStandardItemModel</code> without removing them physically from the model?</p>
  
  <p>Rational: I want to not display entities which are shown in another view. I already have a working highlight logic for that in the <code>data</code> function. Could I turn it(easily) in a "not display logic", so such rows are skipped?</p>
  
  <pre><code>    QVariant CMyModel::data(const QModelIndex &amp;index, int role) const
      {
          if (role != Qt::BackgroundRole) { return CModelBase::data(index, role); }
          .......
  
          if (model.hasSomeCondition())
          {
             static const QBrush b(Qt::green);
             return b;
          }
          return QVariant();
      }
  </code></pre>