Pyqt5 threading can't work (Fatal Python error: could not acquire lock)

Question

我已经阅读了很多关于此的 QThread 教程和 SO Answers。但是我不能让我的线程工作。大多数时候，它只是运行一次或打印错误消息。如果我在应用程序启动后立即启动线程，线程会工作，但我希望线程在特定功能后运行，因为我想先设置目录位置。

文件结构是这样排列的：

App.py
Controllers/
    main_controller.py
    recorder.py
Model/
    model.py
Views/
    main_view.py

App.py

import sys
from PyQt5.QtWidgets import QApplication

from Model.model import Model
from Controllers.main_controller import MainController
from Views.main_view import MainView


class App(QApplication):
    def __init__(self, sys_argv):
        super().__init__(sys_argv)
        self.model = Model()
        self.main_controller = MainController(self.model)
        self.main_view = MainView(self.model, self.main_controller)


if __name__ == "__main__":
    app = App(sys.argv)
    sys.exit(app.exec_())

model.py

from PyQt5.QtCore import QObject


class Model(QObject):
    def __init__(self):
        super().__init__()
        self.directory = ""

    def get_directory(self):
        return self.directory

    def set_directory(self, directory):
        self.directory = directory

main_view.py

from PyQt5.QtWidgets import QMenu, QSystemTrayIcon, QMainWindow, QFileDialog
from PyQt5 import QtGui
from PyQt5.QtWidgets import QApplication
from Controllers.recorder import Recorder


class MainView(QMainWindow):

    def __init__(self, model, main_controller):
        super().__init__()

        self._model = model
        self._main_controller = main_controller

        # UI
        icon = QtGui.QIcon("icon24x24.png")
        menu = QMenu()
        start_action = menu.addAction("Start Recording")
        stop_action = menu.addAction("Stop Recording")
        self.tray = QSystemTrayIcon()
        self.tray.setIcon(icon)
        self.tray.setContextMenu(menu)
        self.tray.show()

        start_action.triggered.connect(self.start_app)
        stop_action.triggered.connect(self.stop_app)

        self.recordThread = Recorder()

    def start_app(self):
        directory = QFileDialog.getExistingDirectory(self, "Select Directory")
        self._main_controller.set_directory(directory)
        self.start_thread()

    def start_thread(self):
        self.recordThread.start()

    def stop_app(self):
        self.recordThread.terminate()
        QApplication.instance().quit()
        print("app stopped")

main_controller.py

from PyQt5.QtCore import QObject


class MainController(QObject):

    def __init__(self, model):
        super().__init__()
        self._model = model

    def set_directory(self, directory):
        self._model.set_directory(directory)

recorder.py

import time
from PyQt5.QtCore import QThread, QTimer, pyqtSignal
from Model.model import Model


class Recorder(QThread):

    job_done = pyqtSignal()

    def __init__(self):
        QThread.__init__(self)
        self._model = Model()

    def __del__(self):
        self.wait()

    def run(self):
        while True:
            print("I am the loop")
            print(self._model.get_directory())
            # time.sleep(4 - time.time() % 4)
            QThread.sleep(4)
            print("now is {}".format(time.time()))
        self.job_done.emit()

我根据各种教程尝试使用各种风格，包括Qthread、QObject、pyqtsignal。但对我没有任何用处。它要么只是打印 "I am the loop" 然后退出。或打印

I am the loop
Fatal Python error: could not acquire lock for <_io.BufferedWriter name='<stdout>'> at interpreter shutdown, possibly due to daemon threads

Thread 0x00007f5d1bfff700 (most recent call first):
  File "/App/Controllers/recorder.py", line 20 in run

Current thread 0x00007f5d3458f700 (most recent call first):
Aborted

谢谢

Answer 1

你的代码没有问题。该应用程序在调用 QFileDialog.getExistingDirectory 后立即关闭，因为这是 Qt 的特性。

Qt is made to exit when all Windows are closed

应用已关闭，因为您不再有任何 windows。您的应用没有任何 windows，但 QSystemTrayIcon()。将 setQuitOnLastWindowClosed() 设置为 False 解决了问题。

yourApp.setQuitOnLastWindowClosed(False)

Pyqt5 threading can't work (Fatal Python error: could not acquire lock)

Pyqt5 threading can't work (Fatal Python error: could not acquire lock)

python

qthread

pyqt5