Close and Open QDialog from QDialog 2

[Axel_Erfurt]

A simple example to open dialog1 on closing dialog2

from PyQt5.QtWidgets import (QMainWindow, QApplication, 
                             QPushButton, QDialog)

class firstDialog(QDialog):
    def __init__(self, parent = None):
        super(firstDialog, self).__init__(parent)
        self.setGeometry(250, 250, 300, 100)
        self.setWindowTitle("Dialog 1")

       
class secondDialog(QDialog):
    def __init__(self, parent = None):
        super(secondDialog, self).__init__(parent)
        self.setGeometry(100, 100, 300, 100)
        self.setWindowTitle("Dialog 2")
                   
    def closeEvent(self, event):
        print("closing secondDialog\n\nopening firstDialog")
        self.firstdial= firstDialog()
        self.firstdial.show()
        event.accept()
            
class mainWin(QMainWindow):
    def __init__(self, parent = None):
        super(mainWin, self).__init__(parent)
        self.setupUI()
        
    def setupUI(self):
        self.setGeometry(0, 0, 400, 300)
        self.tb = self.addToolBar("TB")
        dialog_btn_1 = QPushButton("show Dialog")
        dialog_btn_1.clicked.connect(self.show_dlg)
        self.tb.addWidget(dialog_btn_1)

        
    def show_dlg(self):
        self.dlg = secondDialog()
        self.dlg.show()


if __name__ == '__main__':
    import sys
    app = QApplication(sys.argv)
    win = mainWin()
    win.setWindowTitle("Main Window")
    win.show()

    sys.exit(app.exec_())