QMdiArea 容纳多文档的窗口 的案例
QMdiSubWindow

import sys

from PyQt5.QtCore import Qt
from PyQt5.QtGui import QIcon
from PyQt5.QtWidgets import QApplication, QWidget, QTableWidget, QTableWidgetItem, QMenu, QVBoxLayout, QMainWindow, \
    QTreeWidget, QTreeWidgetItem, QHBoxLayout, QPushButton, QInputDialog, QDirModel, QTreeView, QTabWidget, QFormLayout, \
    QLineEdit, QRadioButton, QLabel, QCheckBox, QListWidget, QStackedWidget, QDockWidget, QMdiArea, QMdiSubWindow, \
    QTextEdit

'''
QMdiArea 容纳多文档的窗口 的案例
QMdiSubWindow

'''


class MultiWindows(QMainWindow):
    count = 0
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        # 设置定位和左上角坐标
        self.setGeometry(300, 300, 360, 360)
        # 设置窗口标题
        self.setWindowTitle('QMdiArea 容纳多文档的窗口 的演示')
        # 设置窗口图标
        # self.setWindowIcon(QIcon('../web.ico'))

        self.mdi = QMdiArea()
        self.setCentralWidget(self.mdi)
        bar = self.menuBar()
        file = bar.addMenu("File")
        file.addAction("New")
        file.addAction("cascade")
        file.addAction("Tiled")

        file.triggered.connect(self.windowaction)

    def windowaction(self,q):
        print(q.text())
        if q.text() == "New":
            MultiWindows.count = MultiWindows.count+1
            sub = QMdiSubWindow()
            sub.setWidget(QTextEdit())
            sub.setWindowTitle("子窗口"+str(MultiWindows.count))
            self.mdi.addSubWindow(sub)
            sub.show()
        elif q.text() == 'cascade':
            self.mdi.cascadeSubWindows()
        elif q.text() == 'Tiled':
            self.mdi.tileSubWindows()



if __name__ == '__main__':
    app = QApplication(sys.argv)
    # 设置应用图标
    app.setWindowIcon(QIcon('../web.ico'))
    w = MultiWindows()
    w.show()
    sys.exit(app.exec_())