pyqt5 QTextDocument 打印字符格式怎么设置

问题遇到的现象和发生背景

insertText() 方法怎么自定义插入不同格式的字符

问题相关代码，请勿粘贴截图

# -*- coding: utf-8 -*-

from PyQt5 import QtCore, QtGui, QtWidgets,QtPrintSupport
from PyQt5.QtGui import QFont,QTextDocument,QTextCursor
from PyQt5.QtPrintSupport import QPrinter, QPrintDialog,QPrintPreviewDialog


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)
        font = QtGui.QFont()
        font.setFamily("楷体")
        font.setPointSize(12)
        font.setBold(False)
        font.setWeight(50)
        MainWindow.setFont(font)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        # 布置一个按钮
        self.pushButton = QtWidgets.QPushButton(self.centralwidget)
        self.pushButton.setGeometry(QtCore.QRect(20, 10, 75, 23))
        self.pushButton.setObjectName("pushButton")
        self.pushButton.setText('打印')
        self.pushButton.clicked.connect(self.on_printAction2_triggered)
        # 布置一个标签
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setGeometry(QtCore.QRect(20, 60, 571, 32))
        font = QtGui.QFont()
        font.setFamily("楷体")
        font.setPointSize(30)
        font.setBold(True)
        self.label.setFont(font)
        self.label.setLineWidth(1)
        self.label.setText("测试字体和大小和格式的标签")
        self.label.setObjectName("label")
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtWidgets.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 22))
        self.menubar.setObjectName("menubar")
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)


    def handlePaintRequest(self,printer):   # 打印函数
        document = QTextDocument()
        cursor = QTextCursor(document)
        try:
            cursor.insertText('\n\n这段文字是默认的字体和大小等格式\n\n')
            cursor.insertText(self.label.text())
            cursor.insertText('\n\n这段文字的字体和大小要重新定义要怎么设置?')
            document.print(printer)
        except Exception as e:
            print(e)


    def on_printAction2_triggered(self):    # 槽函数
        dialog = QPrintPreviewDialog()
        dialog.paintRequested.connect(self.handlePaintRequest)
        dialog.exec_()


    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "打印测试"))

# 程序入口
if __name__ == '__main__':
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec())

运行结果及报错内容

我的解答思路和尝试过的方法

我想要达到的结果

控件字体样式等设置 有几种情况：

self.btnStep.setStyleSheet("QPushButton{font-family:'微软雅黑';font-size:16px;"
"color:#ADD8E6;background-color:#F0F0F0;text-align: left}")

self.textedit.setStyleSheet('background-color: rgb(33, 33, 33);'
'border-color: rgb(18, 18, 18);'
'color: rgb(255, 255, 255);'
'font: bold italic 20pt "Times New Roman";' )

self.lineEdit.setStyleSheet("color:red");//文本颜色
self.lineEdit.setStyleSheet("background-color:red");//背景色

self.textEdit.append("<font color="#0000FF">\n 1. 图像变换") # 显示蓝色

self.lineEdit.setText("<font color="#0000FF">\n 保存图像...") # 显示蓝色

self.textBrowser.setFont(font) # 视图-浏览器字体/大小设置
self.textBrowser.setTextColor(col) # 视图-浏览器字体颜色设置

self.lineEdit.setStyleSheet("color:rgb(10,10,10,255);font-size:25px;font-weight:bold;font-family:Roman times;")

def dispText(self):
    self.fontName=self.ui.listWidgetFont.currentItem().text()
    self.fontSize=int(self.ui.comboBoxFontSize.itemText(self.ui.comboBoxFontSize.currentIndex()))
    self.textToDraw=self.ui.textEdit.toPlainText()

cursor.insertText("\n 设置这段文字的字体和大小"

 cursor.insertText("<font color="#0000FF" font size="12">\n 设置这段文字的字体和大小"

import sys
from PyQt5.QtWidgets import *
from PyQt5.QtGui import QColor, QFont
from PyQt5.QtCore import Qt
from PyQt5.QtPrintSupport import QPrinter, QPrintDialog, QPrintPreviewDialog


class App(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle("PyQt5 颜色/字体/打印相关对话框")
        vlayout = QVBoxLayout()
        bt1 = QPushButton("字体对话框")
        bt2 = QPushButton("颜色对话框(字体颜色)")
        bt2_ = QPushButton("字体背景颜色")
        bt3 = QPushButton("打印预览对话框")
        bt4 = QPushButton("打印对话框")
        self.textEdit = QTextEdit()  # 初始化时换行符无效
        self.textEdit.setText("第一行\n第二行\n第三行\n")
        self.textEdit.selectAll()

        vlayout.addWidget(bt1)
        vlayout.addWidget(bt2)
        vlayout.addWidget(bt2_)
        vlayout.addWidget(bt3)
        vlayout.addWidget(bt4)
        vlayout.addWidget(self.textEdit)
        self.setLayout(vlayout)

        bt1.clicked.connect(self.font_setup)
        bt2.clicked.connect(self.textcolor_setup)
        bt2_.clicked.connect(self.textbgcolor_setup)
        bt3.clicked.connect(self.printPreview)
        bt4.clicked.connect(self.print_setup)
        self.resize(400, 400)

    def font_setup(self):
        font, ok = QFontDialog.getFont()
        if ok:
            # print((font.family(), font.pointSize(), font.bold(), font.italic(),font.underline(),font.strikeOut()))
            print("字体：%s" % font.family())
            print("字号：%s" % font.pointSize())
            print("是否粗体：%s" % font.bold())
            print("是否斜体：%s" % font.italic())
            print("是否加下划线：%s" % font.underline())
            print("是否加删除线：%s" % font.strikeOut())
            self.textEdit.setCurrentFont(font)
            '''
            QTextEdit 其他 字体设置相关的方法。
            font = self.textEdit.currentFont()
            self.textEdit.setFontFamily (self, QString fontFamily)
            self.textEdit.setFontItalic (self, bool b)
            self.textEdit.setFontPointSize (self, float s)
            self.textEdit.setFontUnderline (self, bool b)
            self.textEdit.setFontWeight (self, int w)
            '''

    def textcolor_setup(self):
        '''
        .getColor.(initial: Union[QColor, Qt.GlobalColor, QGradient] = Qt.white, parent: QWidget = None, title: str = '',
                    options: Union[QColorDialog.ColorDialogOptions, QColorDialog.ColorDialogOption] = QColorDialog.ColorDialogOptions())
        '''
        color = QColorDialog.getColor()  # 使用默认参数
        if color.isValid():
            self.textEdit.setTextColor(color)
            print(color.getRgb())  # 整形 RGBA
            print(color.getRgbF())  # 浮点型 RGBA
        '''
        .setTextBackgroundColor (self, QColor c)
        .setTextColor (self, QColor c)
        self.textEdit.textBackgroundColor (self)
        self.textEdit.textColor (self)
        '''

    def textbgcolor_setup(self):
        color = QColorDialog.getColor(Qt.white, None, '选择文字背景颜色', QColorDialog.ShowAlphaChannel)
        # color =QColorDialog.getColor(Qt.white,None, '选择文字背景颜色',QColorDialog.NoButtons )
        print(color.getRgb())
        if color.isValid():
            self.textEdit.setTextBackgroundColor(color)

    def printPreview(self):  # 打印预览
        dialog = QPrintPreviewDialog()
        dialog.paintRequested.connect(self.handlePrint)
        dialog.exec_()

    def print_setup(self):  # 打印，无预览
        printer = QPrinter()
        dialog = QPrintDialog(printer, self)
        if dialog.exec_() == QDialog.Accepted:
            self.handlePrint(printer)

    def handlePrint(self, printer):  # 打印方法
        self.textEdit.print(printer)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = App()
    ex.show()
    sys.exit(app.exec_())