how to make a dialog or a popup window can stay behind the mainwindow and don't cover the mainwindow

Question

I am new to pyqt5, I want pop-up a window and let the window can stay behinde the mainwindow and not clickable(smiliar like let the new window as an another process window)

import sys
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *

class Demo(QMainWindow):
    def __init__(self):
        super().__init__()
        test_button = QPushButton('test')
        test_button.clicked.connect(self.onClick)
        self.setCentralWidget(test_button)

    def onClick(self):
        # dlg = QDialog(self)
        dlg = QMainWindow(self)
        dlg.setWindowFlag(Qt.WindowStaysOnTopHint, False)
        dlg.show()

app = QApplication([])
demo = Demo()
demo.show()
app.exec()

the new window is always stay on the mainwindow, I need to the window stay behide it.

Answer 1

void QWidget::move(int x, int y)

import sys
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *


class Demo(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle('Main Window')
        test_button = QPushButton('test')
        test_button.clicked.connect(self.onClick)
        self.setCentralWidget(test_button)

    def onClick(self):
        # dlg = QDialog(self)
        dlg = QMainWindow(self)
        dlg.setWindowTitle('Dialog Window')

        dlg.move(self.geometry().x() + self.geometry().width() + 30,         # <---
                 self.geometry().y() - 30)

        dlg.setWindowFlag(Qt.WindowStaysOnTopHint, False)
        dlg.show()

    def sizeHint123(self):
        return QSize(200, 200)

app = QApplication([])
demo = Demo()
demo.show()
app.exec()

---

Update

import sys
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *


class Demo(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle('Main Window')

        self.setWindowFlags(Qt.WindowStaysOnTopHint)                            # +++

        test_button = QPushButton('test')
        test_button.clicked.connect(self.onClick)
        self.setCentralWidget(test_button)

    def onClick(self):
        # dlg = QDialog(self)
        self.dlg = QMainWindow()                                                 # --- self
        self.dlg.setWindowTitle('Dialog Window')

        self.dlg.move(self.geometry().x() + self.geometry().width() + 30,         
                 self.geometry().y() - 30)

#        dlg.setWindowFlag(Qt.WindowStaysOnTopHint, False)
        self.dlg.show()

    def sizeHint123(self):
        return QSize(200, 200)

app = QApplication([])
demo = Demo()
demo.show()
app.exec()