QTreeWidget::topLevelItem() results in seg fault.

[johnny_sparx]

Originally, I posted about a problem I was having, but got no response:

I had a QTreeView and wanted to change the color of one of the entries in the view. I opted to change the QTreeView into a QTreeWidget and called QTreeView::setModel() to set my model to match the view.

While the model-view interface works fine, I seem to get a segmentation fault when I do the following in a member function:

void DatabaseTreeWidget::Update_Tree_From_Flags()
{
  QTreeWidgetItem *X;
 
  X = topLevelItem(0);
  X->setTextColor(1,QColor(Qt::darkGreen));
}

void DatabaseTreeWidget::Update_Tree_From_Flags()
{
  QTreeWidgetItem *X;

  X = topLevelItem(0);
  X->setTextColor(1,QColor(Qt::darkGreen));
}

To copy to clipboard, switch view to plain text mode 

Why does this happen? I want to change the color of the top level tree item, but am clearly having difficulty.