[code python]# -*- coding: utf-8 -*-
from PyQt5.QtWidgets import *
from PyQt5.QtGui import QPalette, QStandardItemModel, QStandardItem
from PyQt5.QtCore import QModelIndex, Qt
 
class SpinBoxDDelegate(QStyledItemDelegate):
    def createEditor(self, parent, opt, ind):
        if ind.row() == 0 and ind.column() == 1:
            editor = QSpinBox()
            editor.setFrame(False)
            editor.setMinimum(1)
            editor.setMaximum(3)
            editor.setSingleStep(1)
            return editor
        elif ind.row() == 1 and ind.column() == 1:
            editor = QSpinBox()
            editor.setFrame(False)
            editor.setMinimum(1)
            editor.setMaximum(1000)
            editor.setSingleStep(5)
            return editor
        else:
            return
    def setEditorData(self, editor, ind):
        val = int(ind.model().data(ind,Qt.EditRole))
        editor.setValue(val)
    def updateEditorGeometry(self, editor, opt, ind):
        editor.setGeometry(opt.rect)
    def setModelData(self, editor, model, ind):
        val = str(editor.value())
        model.setData(ind,val,Qt.EditRole)
 
class NM_MainWindow(QWidget):
    def __init__(self):
        super().__init__()
        self.resize(1200, 800)
        self.sys_dev = QTreeView(self)
        self.sys_dev.resize(600,500)
        item11 = QStandardItem('Система')
        sti = QStandardItemModel()
        item12 = QStandardItem('1')
        item21 = QStandardItem('Плотность')
        item22 = QStandardItem('36')
        item31 = QStandardItem('a0/b0')
        item32 = QStandardItem('2')
        sti.appendRow([item11, item12])
        sti.appendRow([item21, item22])
        sti.appendRow([item31, item32])
        self.sys_dev.setModel(sti)
        self.sys_dev.setItemDelegate(SpinBoxDDelegate())
if __name__ == "__main__":
    import sys
    app = QApplication(sys.argv)
    mui = NM_MainWindow()
    mui.show()
    sys.exit(app.exec_())[/code]

 editor = QSpinBox(parent)

 class fraimDelegate(QStyledItemDelegate):
    def paint(self, painter, opt, ind):
        painter.save()
        painter.setPen(Qt.gray)
        x = opt.rect.x()
        y = opt.rect.y()
        h = opt.rect.height()
        w = opt.rect.width()
        if ind.column() == 0:
            w = w + x
            x = 0
        painter.drawRect(x,y,w,h)
        painter.restore()

 QStyledItemDelegate.paint(self, painter, opt, ind)