pyqt4中的线程错误

Question

我有问题。 我创建了线程，然后从那里打开新窗口。 但这行不通。

import sys
from grab import Grab
from PyQt4 import QtGui, QtCore
class Requests(QtCore.QThread):
    def __init__(self, parent=None):
        QtCore.QThread.__init__(self, parent)

    def run(self):
        # here some comands
        self.emit(QtCore.SIGNAL("mysignal(QString)"), 'open')

class window(QtGui.QWidget):
    def __init__(self, parent = None):
        QtGui.QWidget.__init__(self, parent)

        self.setGeometry(100, 100, 500, 200)
        self.setWindowTitle('Window')
        self.label = QtGui.QLabel(u'Hello')
        self.Layout = QtGui.QVBoxLayout()
        self.Layout.addWidget(self.label)
        self.setLayout(self.Layout)

        self.c = Requests()
        self.c.start()
        self.connect(self.c, QtCore.SIGNAL("mysignal(QString)"), self.open_window, QtCore.Qt.QueuedConnection)

    def open_window(self):
        print 'open modal window'
        modal_w = popup_window()
        modal_w.show()

app = QtGui.QApplication(sys.argv)
main = window()
main.show()
sys.exit(app.exec_())

它不显示新窗口。 错误在哪里？

Answer 1

您需要在线程启动之前（因此在发出信号之前）连接信号。 如果要在工作线程完成时显示对话框，请使用finished信号：

class Requests(QtCore.QThread):    
    def run(self):
        # do some work...
        print 'work finished'

    ...
    self.c = Requests()
    self.c.finished.connect(self.open_window)
    self.c.start()

在插槽中打开对话框时，还需要保留对对话框的引用：

    def open_window(self):
        print 'open modal window'
        self.modal_w = popup_window()
        self.modal_w.show()