为什么我不能在类的成员函数中初始化QThread？

  • Z时代
  • 2024-01-10
  • 分类：问答

下面是代码：为什么我不能在类的成员函数中初始化QThread？

########################################################## 
######## Version 1 (works) 
########################################################## 
#!/usr/bin/env python3 
from ui.qthreadtest import Ui_QthreadTest 
from PySide import QtCore, QtGui 
import time 
class Md(QtGui.QDialog): 
    def __init__(self): 
     super().__init__() 
     self.prcsbtn = QtGui.QPushButton("Process") 
     self.prcsedit = QtGui.QLineEdit() 
     layout = QtGui.QHBoxLayout() 
     layout.addWidget(self.prcsedit) 
     layout.addWidget(self.prcsbtn) 
     self.setLayout(layout) 
     self.prcsbtn.clicked.connect(self.work) 
     self.wt = Worker() 
    def work(self): 
     self.wt.start() 
     # the DirectConnection option demands the slot to be triggered immediately 
     self.wt.workFinished.connect(self.changeText, QtCore.Qt.DirectConnection) 
    def changeText(self): 
     self.prcsedit.setText("Work finished!") 
class Worker(QtCore.QThread): 
    workFinished = QtCore.Signal() 
    def __init__(self): 
     super().__init__() 
    def run(self): 
     time.sleep(2) 
     self.workFinished.emit() 
import sys 
app = QtGui.QApplication(sys.argv) 
md = Md() 
md.show() 
sys.exit(app.exec_()) 
########################################################## 
######## Version 2 (doesn't work)  
########################################################## 
#!/usr/bin/env python3 
from ui.qthreadtest import Ui_QthreadTest 
from PySide import QtCore, QtGui 
import time 
class Md(QtGui.QDialog): 
    def __init__(self): 
     super().__init__() 
     self.prcsbtn = QtGui.QPushButton("Process") 
     self.prcsedit = QtGui.QLineEdit() 
     layout = QtGui.QHBoxLayout() 
     layout.addWidget(self.prcsedit) 
     layout.addWidget(self.prcsbtn) 
     self.setLayout(layout) 
     self.prcsbtn.clicked.connect(self.work) 
    def work(self): 
     # the worker thread initialized in a member function won't work. 
     wt = Worker() 
     wt.start() 
     # the DirectConnection option demands the slot to be triggered immediately 
     wt.workFinished.connect(self.changeText, QtCore.Qt.DirectConnection) 
    def changeText(self): 
     self.prcsedit.setText("Work finished!") 
class Worker(QtCore.QThread): 
    workFinished = QtCore.Signal() 
    def __init__(self): 
     super().__init__() 
    def run(self): 
     time.sleep(2) 
     self.workFinished.emit() 
import sys 
app = QtGui.QApplication(sys.argv) 
md = Md() 
md.show() 
sys.exit(app.exec_())

1件作品OK，版本2给出了这样的错误（而破碎瞬间，当处理按钮被按下）：

QThread: Destroyed while thread is still running 
Process finished with exit code 139

回答：

发生这种情况，因为不像threading.Thread对象，QThread对象一旦超出范围就会被销毁。在你的例子中，当work结束时wt超出范围，因此对象被破坏。为了避免这种情况，您需要持续参考wt。这样做的一个方法是使一个实例变量：

def work(self): 
    self.wt = Worker() 
    self.wt.start() 
    # the DirectConnection option demands the slot to be triggered immediately 
    self.wt.workFinished.connect(self.changeText, QtCore.Qt.DirectConnection)

以上是 为什么我不能在类的成员函数中初始化QThread？ 的全部内容， 来源链接： utcz.com/qa/263605.html

回到顶部