PyQt5中建立二级窗口

用qtdesigner创建两个窗口，在主窗口里面放置一个按钮，用pyuic解析为py文件。

主窗口文件名one.py，二级窗口文件名main_window_v1.py。 

import sys
import one
import main_window_v1
from PyQt5.QtWidgets import *


class SecondWindow(QMainWindow, main_window_v1.Ui_MainWindow):
    def __init__(self):
        super(SecondWindow, self).__init__()
        self.setupUi(self)

    def open(self):
        second.show()


class MainWindow(QMainWindow, one.Ui_Form):
    def __init__(self):
        super(MainWindow, self).__init__()
        self.setupUi(self)
        self.pushButton.clicked.connect(SecondWindow.open)


if __name__ == "__main__":
    app = QApplication(sys.argv)
    win = MainWindow()
    second = SecondWindow()
    win.show()
    sys.exit(app.exec_())

参考：

PyQt5 + qtdesigner 多窗口设计/多页面显示_qtdesigner设计多窗口-CSDN博客

PyQt5-打开新窗口（多窗口）_哔哩哔哩_bilibili