PyQt5-QTextEdit 文本追加和分行

#!/usr/bin/env python3
# Author：1626478661
# Date：2016-09-06 15:28:21
# PyQt5 QTextEdit
from PyQt5 import QtWidgets, QtCore, QtGui
from PyQt5.QtWidgets import (QPushButton, QLineEdit, QTextEdit, QWidget, QHBoxLayout, QVBoxLayout, QApplication)
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QTextCursor
import sys
import time


class Windows(QWidget):
    def __init__(self):
        super(Windows, self).__init__()

        self.setWindowTitle('PyQt5 QTextEdit © QQ 1626478661')
        self.setFixedSize(300, 150)

        # IP address / Hostname
        self.IPHostnameEdit = QLineEdit()
        self.IPHostnameEdit.setPlaceholderText('IP address or Hostname')
        self.IPHostnameButton = QPushButton('追加')
        self.IPHostnameButton.clicked.connect(self.checkButton)

        self.IPHostnameButton02 = QPushButton('分行')
        self.IPHostnameButton02.clicked.connect(self.checkButton02)

        self.IPHostnameButton03 = QPushButton('调试')
        self.IPHostnameButton03.clicked.connect(self.getText)
        # Message / Log
        self.showLogText = QTextEdit()
        print(time.strftime("%F %T"))
        self.showLogText.setText("{0} initializing...".format(time.strftime("%F %T")))
        # self.showLogText.setText("""车道中心线\n车道中心线\n车道中心线""")

        # layout for IPHostname
        self.IPHostnameLayout = QHBoxLayout()
        self.IPHostnameLayout.addWidget(self.IPHostnameEdit)
        self.IPHostnameLayout.addWidget(self.IPHostnameButton)
        self.IPHostnameLayout.addWidget(self.IPHostnameButton02)
        self.IPHostnameLayout.addWidget(self.IPHostnameButton03)

        # layout
        self.mainLayout = QVBoxLayout()
        self.mainLayout.addLayout(self.IPHostnameLayout)
        self.mainLayout.addWidget(self.showLogText)

        self.setLayout(self.mainLayout)

        # Disable zoom- / zoom+
        self.setWindowFlags(Qt.WindowCloseButtonHint)

    # Function for check Button
    def checkButton(self):
        self.showLogText.moveCursor(QTextCursor.End)
        self.showLogText.insertPlainText(self.IPHostnameEdit.text())

    def checkButton02(self):
        self.showLogText.moveCursor(QTextCursor.End)
        self.showLogText.append(self.IPHostnameEdit.text())

    def getText(self):
        txt = self.showLogText.toPlainText()
        s = txt.split('\n')
        print(s)

app = QApplication(sys.argv)
win = Windows()
win.show()
app.exec_()