PyQt 使用QMessageBox卡死问题

错误1

• Process finished with exit code -1073741819 (0xC0000005)
QMessageBox 需要在主线程中使用，不能在子线程中使用。

import sys
import time
from PyQt5.QtWidgets import QWidget, QApplication, QMessageBox
from PyQt5.QtCore import QThread, pyqtSignal

class MyTask(QThread):
    def run(self):
        time.sleep(5)
        QMessageBox.warning(None, 'error', 'error msg')

class Win(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.resize(600, 400)
        self.t = None
        self.test()

    def test(self):
        self.t = MyTask()
        self.t.start()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    win = Win()
    win.show()
    app.exec_()

错误2

• Process finished with exit code -1073740791 (0xC0000409)
  变量 t 需要改为类级变量，self.t

import sys
import time
from PyQt5.QtWidgets import QWidget, QApplication, QMessageBox
from PyQt5.QtCore import QThread, pyqtSignal

class MyTask(QThread):
    sig = pyqtSignal(object)

    def run(self):
        time.sleep(5)
        self.sig.emit('111111111')

class Win(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.resize(600, 400)
        t = MyTask()
        t.sig.connect(self.out)
        t.start()

    def out(self, obj):
        QMessageBox.warning(None, 'error', obj)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    win = Win()
    win.show()
    app.exec_()

正确

import sys
import time
from PyQt5.QtWidgets import QWidget, QApplication, QMessageBox
from PyQt5.QtCore import QThread, pyqtSignal

class MyTask(QThread):
    sig = pyqtSignal(object)

    def run(self):
        time.sleep(5)
        self.sig.emit('111111111')

class Win(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.resize(600, 400)
        self.t = MyTask()
        self.t.sig.connect(self.out)
        self.t.start()

    def out(self, obj):
        QMessageBox.warning(None, 'error', obj)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    win = Win()
    win.show()
    app.exec_()

注意：窗口显示必须搞到主线程中去管理不能在子线程中去调用显示，否则就会导致页面卡死。

参考