hello, I try to change color of several QTreeWidgetItem without change text format by defaut.
my code :
Qt Code: 
  1. class test(QStyledItemDelegate):
  2. 		def __init__(self, parent=None, *args):
  3. 			QItemDelegate.__init__(self, parent, *args)
  4.  
  5. 		def lin(self,col1,col2):
  6. 			o = QLinearGradient(QPointF(100, 100), QPointF(200, 200))
  7. 			o.setColorAt(0,col1); 
  8. 			o.setColorAt(1, col2);  
  9. 			return QBrush(o)
  10.  
  11. 		def paint(self, painter, option, index):
  12.  
  13. 			painter.save()
  14.  
  15. 			# set background color
  16. 			if index.sibling(index.row(),0).data(Qt.DisplayRole).toString() == "Formule":
  17. 				if option.state & QStyle.State_Selected:
  18. 					painter.setBrush( self.lin(QColor(0,0,200,100),QColor("#567dbc")) ) # Formule selected background color
  19. 				else:
  20. 					painter.setBrush(QBrush(QColor(0,100,100,150))) # Formule Normal background color
  21. 				painter.setPen(QPen(QBrush(QColor("#d9d9d9")),2.0)) # Formule Border color
  22. 				painter.drawRect(option.rect)
  23. 			else:
  24. 				if option.state & QStyle.State_Selected:
  25. 					painter.setBrush( self.lin(QColor(0,100,200,100),QColor("#567dbc")) ) #selected background color
  26. 				else:
  27. 					painter.setBrush(QBrush(Qt.white)) #Normal background color
  28. 				painter.setPen(QPen(QBrush(QColor("#d9d9d9")),2.0)) # Border color
  29. 				painter.drawRect(option.rect)
  30. 			# set text color
  31. 			painter.setPen(QPen(Qt.black))
  32. 			value = index.data(Qt.DisplayRole)
  33. 			if value.isValid():
  34. 				text = value.toString()
  35. 				painter.drawText(option.rect,Qt.AlignCenter, text)
  36.  
  37. 			painter.restore()
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with this code, text is more small, the font size is not shrink if text is too big and i can't choose align text when a create QTreeWidgetItem
someone know how too change color whithout change text formating ?

Sorry for my bad english.