效果图：
这次添加了关闭-撤销-重做-全选-清空等功能，并添加了字体和字体大小选择。基本方法跟前面几篇类似。
ui_mainWindow.py
# -*- coding: utf-8 -*- # Form implementation generated from reading ui file 'ui_mainWindow.ui' # # Created by: PyQt5 UI code generator 5.13.0 # # WARNING! All changes made in this file will be lost! from PyQt5 import QtCore, QtGui, QtWidgets class Ui_MainWindow(object): def setupUi(self, MainWindow): MainWindow.setObjectName("MainWindow") MainWindow.resize(691, 367) self.centralwidget = QtWidgets.QWidget(MainWindow) self.centralwidget.setObjectName("centralwidget") self.plainTextEdit = QtWidgets.QPlainTextEdit(self.centralwidget) self.plainTextEdit.setGeometry(QtCore.QRect(0, 0, 691, 291)) font = QtGui.QFont() font.setPointSize(18) self.plainTextEdit.setFont(font) self.plainTextEdit.setObjectName("plainTextEdit") MainWindow.setCentralWidget(self.centralwidget) self.menubar = QtWidgets.QMenuBar(MainWindow) self.menubar.setGeometry(QtCore.QRect(0, 0, 691, 21)) self.menubar.setObjectName("menubar") self.menu = QtWidgets.QMenu(self.menubar) self.menu.setObjectName("menu") self.menu_2 = QtWidgets.QMenu(self.menubar) self.menu_2.setObjectName("menu_2") self.menu_3 = QtWidgets.QMenu(self.menubar) self.menu_3.setObjectName("menu_3") MainWindow.setMenuBar(self.menubar) self.toolBar = QtWidgets.QToolBar(MainWindow) self.toolBar.setToolButtonStyle(QtCore.Qt.ToolButtonIconOnly) self.toolBar.setObjectName("toolBar") MainWindow.addToolBar(QtCore.Qt.TopToolBarArea, self.toolBar) self.statusBar = QtWidgets.QStatusBar(MainWindow) self.statusBar.setObjectName("statusBar") MainWindow.setStatusBar(self.statusBar) self.actFont_Italic = QtWidgets.QAction(MainWindow) self.actFont_Italic.setCheckable(True) icon = QtGui.QIcon() icon.addPixmap(QtGui.QPixmap("icons/images/Italic.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actFont_Italic.setIcon(icon) self.actFont_Italic.setObjectName("actFont_Italic") self.actFont_Bold = QtWidgets.QAction(MainWindow) self.actFont_Bold.setCheckable(True) icon1 = QtGui.QIcon() icon1.addPixmap(QtGui.QPixmap("icons/images/Bold.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actFont_Bold.setIcon(icon1) self.actFont_Bold.setObjectName("actFont_Bold") self.actFont_Underline = QtWidgets.QAction(MainWindow) self.actFont_Underline.setCheckable(True) icon2 = QtGui.QIcon() icon2.addPixmap(QtGui.QPixmap("icons/images/underline.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actFont_Underline.setIcon(icon2) self.actFont_Underline.setObjectName("actFont_Underline") self.actEdit_Cut = QtWidgets.QAction(MainWindow) self.actEdit_Cut.setEnabled(False) icon3 = QtGui.QIcon() icon3.addPixmap(QtGui.QPixmap("icons/images/cut.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actEdit_Cut.setIcon(icon3) self.actEdit_Cut.setObjectName("actEdit_Cut") self.actEdit_Copy = QtWidgets.QAction(MainWindow) self.actEdit_Copy.setEnabled(False) icon4 = QtGui.QIcon() icon4.addPixmap(QtGui.QPixmap("icons/images/copy.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actEdit_Copy.setIcon(icon4) self.actEdit_Copy.setObjectName("actEdit_Copy") self.actEdit_Paste = QtWidgets.QAction(MainWindow) self.actEdit_Paste.setEnabled(False) icon5 = QtGui.QIcon() icon5.addPixmap(QtGui.QPixmap("icons/images/paste.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actEdit_Paste.setIcon(icon5) self.actEdit_Paste.setObjectName("actEdit_Paste") self.actFile_New = QtWidgets.QAction(MainWindow) icon6 = QtGui.QIcon() icon6.addPixmap(QtGui.QPixmap("icons/images/new.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actFile_New.setIcon(icon6) self.actFile_New.setObjectName("actFile_New") self.actFile_Open = QtWidgets.QAction(MainWindow) icon7 = QtGui.QIcon() icon7.addPixmap(QtGui.QPixmap("icons/images/open.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actFile_Open.setIcon(icon7) self.actFile_Open.setObjectName("actFile_Open") self.actFile_Save = QtWidgets.QAction(MainWindow) icon8 = QtGui.QIcon() icon8.addPixmap(QtGui.QPixmap("icons/images/save.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actFile_Save.setIcon(icon8) self.actFile_Save.setObjectName("actFile_Save") self.actClose = QtWidgets.QAction(MainWindow) icon9 = QtGui.QIcon() icon9.addPixmap(QtGui.QPixmap("icons/images/close.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actClose.setIcon(icon9) self.actClose.setObjectName("actClose") self.actEdit_Undo = QtWidgets.QAction(MainWindow) self.actEdit_Undo.setEnabled(False) icon10 = QtGui.QIcon() icon10.addPixmap(QtGui.QPixmap("icons/images/undo.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actEdit_Undo.setIcon(icon10) self.actEdit_Undo.setObjectName("actEdit_Undo") self.acEdit_Redo = QtWidgets.QAction(MainWindow) self.acEdit_Redo.setEnabled(False) icon11 = QtGui.QIcon() icon11.addPixmap(QtGui.QPixmap("icons/images/redo.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.acEdit_Redo.setIcon(icon11) self.acEdit_Redo.setObjectName("acEdit_Redo") self.actEdit_Clear = QtWidgets.QAction(MainWindow) icon12 = QtGui.QIcon() icon12.addPixmap(QtGui.QPixmap("icons/images/clear.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actEdit_Clear.setIcon(icon12) self.actEdit_Clear.setObjectName("actEdit_Clear") self.actEdit_SelectAll = QtWidgets.QAction(MainWindow) self.actEdit_SelectAll.setObjectName("actEdit_SelectAll") self.actLang_CN = QtWidgets.QAction(MainWindow) self.actLang_CN.setCheckable(True) icon13 = QtGui.QIcon() icon13.addPixmap(QtGui.QPixmap("icons/images/chinese.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actLang_CN.setIcon(icon13) self.actLang_CN.setObjectName("actLang_CN") self.actLang_EN = QtWidgets.QAction(MainWindow) self.actLang_EN.setCheckable(True) icon14 = QtGui.QIcon() icon14.addPixmap(QtGui.QPixmap("icons/images/English.jpg"), QtGui.QIcon.Normal, QtGui.QIcon.Off) self.actLang_EN.setIcon(icon14) self.actLang_EN.setObjectName("actLang_EN") self.menu.addAction(self.actFile_New) self.menu.addAction(self.actFile_Open) self.menu.addAction(self.actFile_Save) self.menu.addSeparator() self.menu.addAction(self.actClose) self.menu_2.addAction(self.actEdit_Cut) self.menu_2.addAction(self.actEdit_Copy) self.menu_2.addAction(self.actEdit_Paste) self.menu_2.addSeparator() self.menu_2.addAction(self.actEdit_Undo) self.menu_2.addAction(self.acEdit_Redo) self.menu_2.addSeparator() self.menu_2.addAction(self.actEdit_SelectAll) self.menu_2.addAction(self.actEdit_Clear) self.menu_3.addAction(self.actFont_Italic) self.menu_3.addAction(self.actFont_Bold) self.menu_3.addAction(self.actFont_Underline) self.menu_3.addSeparator() self.menubar.addAction(self.menu.menuAction()) self.menubar.addAction(self.menu_2.menuAction()) self.menubar.addAction(self.menu_3.menuAction()) self.toolBar.addAction(self.actFile_New) self.toolBar.addAction(self.actFile_Open) self.toolBar.addAction(self.actFile_Save) self.toolBar.addSeparator() self.toolBar.addAction(self.actEdit_Cut) self.toolBar.addAction(self.actEdit_Copy) self.toolBar.addAction(self.actEdit_Paste) self.toolBar.addSeparator() self.toolBar.addAction(self.actEdit_Undo) self.toolBar.addAction(self.acEdit_Redo) self.toolBar.addSeparator() self.toolBar.addAction(self.actFont_Italic) self.toolBar.addAction(self.actFont_Bold) self.toolBar.addAction(self.actFont_Underline) self.toolBar.addSeparator() self.toolBar.addAction(self.actLang_CN) self.toolBar.addAction(self.actLang_EN) self.toolBar.addSeparator() self.retranslateUi(MainWindow) self.actEdit_Cut.triggered.connect(self.plainTextEdit.cut) self.actEdit_Copy.triggered.connect(self.plainTextEdit.copy) self.actEdit_Paste.triggered.connect(self.plainTextEdit.paste) self.actClose.triggered.connect(MainWindow.close) self.actEdit_Undo.triggered.connect(self.plainTextEdit.undo) self.acEdit_Redo.triggered.connect(self.plainTextEdit.redo) self.actEdit_Clear.triggered.connect(self.plainTextEdit.clear) self.actEdit_SelectAll.triggered.connect(self.plainTextEdit.selectAll) self.plainTextEdit.undoAvailable['bool'].connect(self.actEdit_Undo.setEnabled) self.plainTextEdit.redoAvailable['bool'].connect(self.acEdit_Redo.setEnabled) QtCore.QMetaObject.connectSlotsByName(MainWindow) def retranslateUi(self, MainWindow): _translate = QtCore.QCoreApplication.translate MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow")) self.menu.setTitle(_translate("MainWindow", "文件(F)")) self.menu_2.setTitle(_translate("MainWindow", "编辑(E)")) self.menu_3.setTitle(_translate("MainWindow", "格式(M)")) self.toolBar.setWindowTitle(_translate("MainWindow", "toolBar")) self.actFont_Italic.setText(_translate("MainWindow", "斜体")) self.actFont_Italic.setToolTip(_translate("MainWindow", "<html><head/><body><p><span style=" font-style:italic;">斜体</span></p></body></html>")) self.actFont_Bold.setText(_translate("MainWindow", "粗体")) self.actFont_Bold.setToolTip(_translate("MainWindow", "加粗")) self.actFont_Underline.setText(_translate("MainWindow", "下划线")) self.actFont_Underline.setToolTip(_translate("MainWindow", "下划线")) self.actEdit_Cut.setText(_translate("MainWindow", "剪切")) self.actEdit_Cut.setToolTip(_translate("MainWindow", "剪切到粘贴板")) self.actEdit_Cut.setShortcut(_translate("MainWindow", "Ctrl+X")) self.actEdit_Copy.setText(_translate("MainWindow", "复制")) self.actEdit_Copy.setToolTip(_translate("MainWindow", "复制到粘贴板")) self.actEdit_Copy.setShortcut(_translate("MainWindow", "Ctrl+C")) self.actEdit_Paste.setText(_translate("MainWindow", "粘贴")) self.actEdit_Paste.setToolTip(_translate("MainWindow", "从粘贴板粘贴")) self.actEdit_Paste.setShortcut(_translate("MainWindow", "Ctrl+V")) self.actFile_New.setText(_translate("MainWindow", "新建")) self.actFile_New.setToolTip(_translate("MainWindow", "新建文件")) self.actFile_New.setShortcut(_translate("MainWindow", "Ctrl+N")) self.actFile_Open.setText(_translate("MainWindow", "打开...")) self.actFile_Open.setToolTip(_translate("MainWindow", "打开文件")) self.actFile_Open.setShortcut(_translate("MainWindow", "Ctrl+O")) self.actFile_Save.setText(_translate("MainWindow", "保存")) self.actFile_Save.setToolTip(_translate("MainWindow", "保存修改")) self.actFile_Save.setShortcut(_translate("MainWindow", "Ctrl+S")) self.actClose.setText(_translate("MainWindow", "关闭")) self.actClose.setToolTip(_translate("MainWindow", "关闭本窗口")) self.actEdit_Undo.setText(_translate("MainWindow", "撤销")) self.actEdit_Undo.setToolTip(_translate("MainWindow", "撤销上次编辑操作")) self.actEdit_Undo.setShortcut(_translate("MainWindow", "Ctrl+Z")) self.acEdit_Redo.setText(_translate("MainWindow", "重做")) self.acEdit_Redo.setToolTip(_translate("MainWindow", "重做上次操作")) self.acEdit_Redo.setShortcut(_translate("MainWindow", "Ctrl+Y")) self.actEdit_Clear.setText(_translate("MainWindow", "清空")) self.actEdit_Clear.setToolTip(_translate("MainWindow", "清空")) self.actEdit_SelectAll.setText(_translate("MainWindow", "全选")) self.actEdit_SelectAll.setToolTip(_translate("MainWindow", "全选")) self.actEdit_SelectAll.setShortcut(_translate("MainWindow", "Ctrl+A")) self.actLang_CN.setText(_translate("MainWindow", "汉语")) self.actLang_CN.setToolTip(_translate("MainWindow", "汉语界面")) self.actLang_EN.setText(_translate("MainWindow", "英语")) self.actLang_EN.setToolTip(_translate("MainWindow", "英语"))
myMainWindow.py
#!/usr/bin/env python # _*_ coding: UTF-8 _*_ """================================================= @Project -> File : Operate-system -> myMainWindow.py @IDE : PyCharm @Author : zihan @Date : 2020/4/11 14:44 @Desc : =================================================""" import sys from PyQt5.QtWidgets import (QApplication, QMainWindow, QActionGroup, QLabel, QProgressBar, QSpinBox, QFontComboBox) from PyQt5.QtCore import Qt, pyqtSlot from PyQt5.QtGui import QTextCharFormat, QFont from ui_mainWindow import Ui_MainWindow class QmyMainWindow(QMainWindow): def __init__(self, parent=None): super().__init__(parent) self.ui = Ui_MainWindow() self.ui.setupUi(self) self.__buildUI() # 设置斜体 self.ui.actFont_Italic.triggered.connect(self.do_act_font_italic_triggered) # 设置粗体 self.ui.actFont_Bold.triggered.connect(self.do_act_font_bold_triggered) # 设置下划线 self.ui.actFont_Underline.triggered.connect(self.do_act_underline_triggered) # 新建文件 self.ui.actFile_New.triggered.connect(self.do_act_file_new_triggered) # 打开文件 self.ui.actFile_Open.triggered.connect(self.do_act_file_open_triggered) # 保存文件 self.ui.actFile_Save.triggered.connect(self.do_act_file_save_triggered) # 设置字体大小 self.__spinFontSize.valueChanged[int].connect(self.do_fontsize_changed) # 字体选择 self.__comboFontName.currentIndexChanged[str].connect(self.do_fontname_changed) # 文本框内容可复制 self.ui.plainTextEdit.copyAvailable.connect(self.do_plain_textedit_copyavailable) # 文本选择内容发生改变 self.ui.plainTextEdit.selectionChanged.connect(self.do_plain_textedit_selectionchanged) # 标准右键菜单 self.ui.plainTextEdit.customContextMenuRequested.connect(self.do_plain_textedit_customctmnreq) self.setCentralWidget(self.ui.plainTextEdit) def __buildUI(self): # 窗体上动态添加组件 # 创建状态栏上的组件 self.__LabFile = QLabel(self) # QLabel组件显示信息 self.__LabFile.setMinimumWidth(150) self.__LabFile.setText("文件名：") self.ui.statusBar.addWidget(self.__LabFile) # 添加到状态栏 self.__progressBar1 = QProgressBar(self) self.__progressBar1.setMaximumWidth(200) self.__progressBar1.setMinimum(5) self.__progressBar1.setMaximum(50) sz = self.ui.plainTextEdit.font().pointSize() # 字体大小 self.__progressBar1.setValue(sz) self.ui.statusBar.addWidget(self.__progressBar1) # 添加到状态栏 self.__LabInfo = QLabel(self) # QLabel组件显示字体名称 self.__LabInfo.setText("选择字体名称：") self.ui.statusBar.addPermanentWidget(self.__LabInfo) # 添加到状态栏 # 为actLang_CN和actLang_EN创建QActionGroup，互斥型选择 actionGroup = QActionGroup(self) actionGroup.addAction(self.ui.actLang_CN) actionGroup.addAction(self.ui.actLang_EN) actionGroup.setExclusive(True) # 互斥型分组 self.ui.actLang_CN.setChecked(True) # 创建工具我是谁，我在哪儿栏上的组件 self.__spinFontSize = QSpinBox(self) # 字体大小spinBox self.__spinFontSize.setMinimum(5) self.__spinFontSize.setMaximum(50) sz = self.ui.plainTextEdit.font().pointSize() self.__spinFontSize.setValue(sz) self.__spinFontSize.setMinimumWidth(50) self.ui.toolBar.addWidget(self.__spinFontSize) # 添加到工具栏 self.__comboFontName = QFontComboBox(self) # 字体comboBox self.__comboFontName.setMinimumWidth(100) self.ui.toolBar.addWidget(self.__comboFontName) # 添加到工具栏 self.ui.toolBar.addSeparator() # 添加一个分隔条 self.ui.toolBar.addAction(self.ui.actClose) # 添加一个关闭按钮 @pyqtSlot(bool) def do_act_font_italic_triggered(self, checked): # 斜体 fmt = self.ui.plainTextEdit.currentCharFormat() fmt.setFontItalic(checked) self.ui.plainTextEdit.mergeCurrentCharFormat(fmt) @pyqtSlot(bool) def do_act_font_bold_triggered(self, checked): # 粗体 fmt = self.ui.plainTextEdit.currentCharFormat() if checked: fmt.setFontWeight(QFont.Bold) else: fmt.setFontWeight(QFont.Normal) self.ui.plainTextEdit.mergeCurrentCharFormat(fmt) @pyqtSlot(bool) def do_act_underline_triggered(self, checked): # 下划线 fmt = self.ui.plainTextEdit.currentCharFormat() fmt.setFontUnderline(checked) self.ui.plainTextEdit.mergeCurrentCharFormat(fmt) def do_act_file_new_triggered(self): # 新建文件，不实现具体功能 self.__LabFile.setText(" 新建文件") def do_act_file_open_triggered(self): # 打开文件，不实现具体功能 self.__LabFile.setText(" 打开的文件") def do_act_file_save_triggered(self): # 保存文件，不实现具体功能 self.__LabFile.setText(" 文件已保存") @pyqtSlot(int) def do_fontsize_changed(self, fontSize): # 设置字体大小 fmt = self.ui.plainTextEdit.currentCharFormat() fmt.setFontPointSize(fontSize) self.ui.plainTextEdit.mergeCurrentCharFormat(fmt) self.__progressBar1.setValue(fontSize) @pyqtSlot(str) def do_fontname_changed(self, fontName): # 设置字体 fmt = self.ui.plainTextEdit.currentCharFormat() fmt.setFontFamily(fontName) self.ui.plainTextEdit.mergeCurrentCharFormat(fmt) self.__LabInfo.setText("字体名称：%s " % fontName) # 文本内容可复制 def do_plain_textedit_copyavailable(self, avi): self.ui.actEdit_Cut.setEnabled(avi) self.ui.actEdit_Copy.setEnabled(avi) self.ui.actEdit_Paste.setEnabled(self.ui.plainTextEdit.canPaste()) # 文本选择内容发生改变时 def do_plain_textedit_selectionchanged(self): fmt = self.ui.plainTextEdit.currentCharFormat() self.ui.actFont_Bold.setChecked(fmt.font().bold()) self.ui.actFont_Italic.setChecked(fmt.fontItalic()) self.ui.actFont_Underline.setChecked(fmt.fontUnderline()) # 标准右键菜单 def do_plain_textedit_customctmnreq(self, pos): popMenu = self.ui.plainTextEdit.createStandardContextMenu() popMenu.exec(pos) # 显示快捷菜单 if __name__ == "__main__": app = QApplication(sys.argv) # 创建app，用QApplication类 form = QmyMainWindow() form.show() sys.exit(app.exec_())
特别提醒一点的是可以自己在Property里面设置剪切-复制-粘贴等的初始状态disable，只需要去掉Enable那个属性的勾就好了。至于怎么使它Enable，对于PlainTextEdit控件来说，有一个槽函数copyAvailable可以设置他们的使能。另外那个customContextMenuRequested(pos)函数在这个程序里面还没发现什么作用，没有什么特别的功能，如果有人发现了，可以告诉我一下，哈哈哈。