第十二篇 -- QMainWindow与QAction（剪切-复制-粘贴）

效果图：

按照上一节的方法，将剪切-复制-粘贴图标放置到工具栏后，为其指定槽函数。这些功能无需自己编写代码来实现，QPlainTextEdit提供了实现这些编辑功能的槽函数，如cut()、copy()、paste()等，只需要将这些Action和相应的槽函数关联即可。

然后将ui转换成py文件，执行即可。

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(532, 367)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.plainTextEdit = QtWidgets.QPlainTextEdit(self.centralwidget)
        self.plainTextEdit.setGeometry(QtCore.QRect(0, 0, 531, 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, 532, 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.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)
        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)
        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)
        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.menubar.addAction(self.menu.menuAction())
        self.menubar.addAction(self.menu_2.menuAction())
        self.menubar.addAction(self.menu_3.menuAction())
        self.toolBar.addAction(self.actFont_Italic)
        self.toolBar.addSeparator()
        self.toolBar.addAction(self.actFont_Bold)
        self.toolBar.addSeparator()
        self.toolBar.addAction(self.actFont_Underline)
        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.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)
        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"))

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)

        # 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)

    @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)

if __name__ == "__main__":
    app = QApplication(sys.argv)  # 创建app，用QApplication类
    form = QmyMainWindow()
    form.show()
    sys.exit(app.exec_())

ok.