Background Colors in QTreeWidget Items / January 2011 / Qt 4.6.3
Excerpts from QtUtils/MassBalSummaryDlg.hpp and .cpp
(before the QTreeWidget was replaced with a QTreeView).

See Image:
http://cadswes2.colorado.edu/~philw/2011/MassBalSum/2012-01-02/images/dlg1.gif
http://cadswes2.colorado.edu/~philw/2011/MassBalSum/2012-01-02/images/dlg2.gif

class MassBalSummaryPanel::TreeItem : public QTreeWidgetItem
{
  ... ... ... 

   private:
     void setBgColor();

  ... ... ...
};

static const QBrush ItemBg_BalGrp  (QColor (0xFF, 0xcc, 0xFF));
static const QBrush ItemBg_Balance (QColor (0xcc, 0xFF, 0xFF));
static const QBrush ItemBg_SlotGrp (QColor (0xFF, 0xFF, 0xcc));
static const QBrush ItemBg_Slot    (QColor (0xcc, 0xFF, 0xcc));

... ... ...

void MassBalSummaryPanel::TreeItem::setBgColor()
{
   QBrush bgBrush = background (0);

   switch (_level)
   {
      case 1: bgBrush = ItemBg_BalGrp;   break;
      case 2: bgBrush = ItemBg_Balance;  break;
      case 3: bgBrush = ItemBg_SlotGrp;  break;
      case 4: bgBrush = ItemBg_Slot;     break;
   }

   const int colCnt = columnCount();
   for (int col = 0; col < colCnt; ++col)
   {
      setBackground (col, bgBrush);
   }
}

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