Is there have relationship between QWidget and QWindow after QWindow detach from QWidget?

richie18

Steps：

Start application A.
Start application B.
Click embed button in application B. Embed the application A to application B.
Click popup button. Popup the application A.
Click block button in application A. Application A run Infinite loop， can not respond to mouse operations.
Application B's process also cannot respond to mouse operations.

What's the reason？

Application B code:

# -*- coding: utf-8 -*-

import sys
import win32gui
from PyQt5.QtGui import QWindow
from PyQt5.QtWidgets import QWidget, QApplication, QVBoxLayout, QHBoxLayout, QPushButton
from PyQt5.QtCore import Qt


class MyWidget(QWidget):
    def __init__(self, parent=None):
	super(MyWidget, self).__init__(parent)
	layout = QVBoxLayout(self)
	btnLayout = QHBoxLayout()
	embedBtn = QPushButton("embed")
	popupBtn = QPushButton("popup")
	btnLayout.addWidget(embedBtn)
	btnLayout.addWidget(popupBtn)
	layout.addLayout(btnLayout)

	embedBtn.clicked.connect(self.embed)
	popupBtn.clicked.connect(self.popup)

	self.window = None
	self.windowWidget = None
	self.hwnd = None
        self.resize(400, 400)

    def embed(self):
	# todo application title must be right
	self.hwnd = win32gui.FindWindow(None, "block application")
	if self.hwnd:
		self.window = QWindow.fromWinId(self.hwnd)
		self.windowWidget = QWidget.createWindowContainer(self.window)
		self.layout().addWidget(self.windowWidget)
		win32gui.SetParent(self.hwnd, int(self.winId()))

    def popup(self):
	self.window.setParent(None)
	self.window.setFlags(Qt.Window)
	self.windowWidget.setParent(None)
	self.windowWidget.destroy()
	win32gui.SetParent(self.hwnd, 0)
	win32gui.UpdateWindow(self.hwnd)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    app.exec_()

Application A code:

# -*- coding: utf-8 -*-

import sys
from PyQt5.QtWidgets import QWidget, QApplication, QVBoxLayout, QPushButton


class MyWidget(QWidget):
    def __init__(self, parent=None):
        super(MyWidget, self).__init__(parent)
        self.setWindowTitle("block application")
        layout = QVBoxLayout(self)
        blockBtn = QPushButton("block process")
        layout.addWidget(blockBtn)

        blockBtn.clicked.connect(self.block)
        self.resize(300, 200)

    def block(self):
        import time
        while True:
	    print(time.time())


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    app.exec_()

richie18

The environment:
Python 3.6.8
PyQt 5.7.1
pywin32-224-cp36-cp36m-win_amd64

SGaist

Hi,

@richie18 said in Is there have relationship between QWidget and QWindow after QWindow pop up?:

Block the application A by manual.

What do you mean by that ?

richie18

@SGaist said in Is there have relationship between QWidget and QWindow after QWindow pop up?:

lock the application A by manua

Block the application A's process after application A pop up from application B. For example, run code in application A below:

import time
while True:
    print(time.time())

richie18

@SGaist

Use code below as application A.
When application A is poped up, click the 'block process' button in applicaiton A. Then application B's process is also blocked.

# -*- coding: utf-8 -*-

import sys
from PyQt5.QtWidgets import QWidget, QApplication, QVBoxLayout, QPushButton


class MyWidget(QWidget):
    def __init__(self, parent=None):
	super(MyWidget, self).__init__(parent)
	self.setWindowTitle("block application")
	layout = QVBoxLayout(self)
	blockBtn = QPushButton("block process")
	layout.addWidget(blockBtn)

	blockBtn.clicked.connect(self.block)
	self.resize(300, 200)

    def block(self):
	import time
	while True:
		print(time.time())


if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    app.exec_()

SGaist

Intriguing... Out of curiosity, what is the use case of "blocking" the application ?

richie18

@SGaist

Maybe I am not expressing correctly.
“blocking” Means that application cannot respond to mouse operations

May be follow the steps below to make it clear.

Steps：

Start application A.
Start application B.
Click embed button in application B. Embed the application A to application B.
Click popup button. Popup the application A.
Click block button in application A. Application A run Infinite loop， can not respond to mouse operations.
Application B's process also cannot respond to mouse operations.

SGaist

I would try to check with the event dispatchers if you can find something there.

richie18

@SGaist

Application A's block() add code processEvents(), it seems ok. But native windows cannot be handled this way.
So, I'm not sure relationship between two application when they are detached. And how to solve?

def block(self):
    import time
    while True:
	print(time.time())
        QApplication.processEvents()

SGaist

You should check the the win32gui module developer, he may have some insight as to what is happening.

richie18

@SGaist

I'm not use win32gui.setParent(), also has this problem.

SGaist

As already suggested, contact the module author.