pyqt 多线程出现问题
import time
from PyQt5.Qt import *
class WorkThread(QThread):
finished=pyqtSignal()
def __init__(self):
super(WorkThread, self).__init__()
self.is_running = None
def run(self):
print('running')
self.is_running = True
while self.is_running:
print('working....')
time.sleep(1)
self.finished.emit()
def stop(self):
self.is_running = False
class MainWindow(QMainWindow):
def __init__(self):
super(MainWindow, self).__init__()
self.resize(600,500)
self.work = WorkThread()
self.work.setParent(self)
self.work.destroyed.connect(lambda :print('thread is destoryed'))
self.btn = QPushButton("start")
self.btn2 = QPushButton("stop")
layout = QVBoxLayout()
layout.addWidget(self.btn)
layout.addWidget(self.btn2)
central_widget = QWidget()
central_widget.setLayout(layout)
self.setCentralWidget(central_widget)
#slots
self.btn.clicked.connect(self.start_thread)
self.btn2.clicked.connect(self.stop_thread)
def start_thread(self):
self.work.start()
def stop_thread(self):
self.work.stop()
def closeEvent(self, event) -> None:
self.work.stop()
在运行时关闭窗口时会出错的原因是，当关闭窗口时，工作线程仍然在运行，并且在调用`self.work.stop()`时，工作线程已经被销毁，但是在`stop()`方法中仍然尝试设置`self.is_running`为False，这会导致AttributeError。
为了解决这个问题，你可以在关闭窗口时先停止工作线程，然后再关闭窗口。你可以在`closeEvent`方法中添加一个判断，如果工作线程正在运行，则先停止工作线程，然后再关闭窗口。代码如下：
```python
def closeEvent(self, event):
if self.work.isRunning():
self.work.stop()
self.work.wait() # 等待工作线程结束
event.accept()
```
这样，当关闭窗口时，会先停止工作线程并等待其结束，然后再关闭窗口，避免了出错的情况。
正确代码如下：
import time
from PyQt5.Qt import *
class WorkThread(QThread):
def __init__(self):
super(WorkThread, self).__init__()
self.is_running = None
def run(self):
print('running')
self.is_running = True
while self.is_running:
print('working....')
time.sleep(1)
def stop(self):
self.is_running = False
class MainWindow(QMainWindow):
def __init__(self):
super(MainWindow, self).__init__()
self.resize(600,500)
self.work = WorkThread()
self.work.setParent(self)
self.work.destroyed.connect(lambda :print('thread is destoryed'))
self.btn = QPushButton("start")
self.btn2 = QPushButton("stop")
layout = QVBoxLayout()
layout.addWidget(self.btn)
layout.addWidget(self.btn2)
central_widget = QWidget()
central_widget.setLayout(layout)
self.setCentralWidget(central_widget)
#slots
self.btn.clicked.connect(self.start_thread)
self.btn2.clicked.connect(self.stop_thread)
def start_thread(self):
self.work.start()
def stop_thread(self):
self.work.stop()
def closeEvent(self, event) -> None:
if self.work.isRunning():
self.work.stop()
self.work.wait()
event.accept()
import time
from PyQt5.Qt import *
import time
qum_1 = QMutex()
class Thread_1(QThread):
def __init__(self):
super(Thread_1, self).__init__()
def run(self):
qum_1.lock()
values=[1,2,3,4,5]
for i in values:
print(i)
time.sleep(0.5)
qum_1.unlock()
class Thread_2(QThread):
_signal = pyqtSignal()
def __init__(self):
super(Thread_2, self).__init__()
def run(self):
values = ["a","b","c","d","e"]
for i in values:
print(i)
time.sleep(1)
self._signal.emit()
class Window(QWidget):
def __init__(self):
super().__init__()
self.setWindowTitle("的学习")
self.resize(500,500)
self.setup_ui()
self.t=Thread_1()
self.t2=Thread_2()
self.t2._signal.connect(lambda :self.btn2.setEnabled(True))
def setup_ui(self):
self.btn = QPushButton('btn1',self)
self.btn.move(10,20)
self.btn.clicked.connect(self.btn_click)
self.btn2 = QPushButton('btn2',self)
self.btn.move(10,80)
self.btn2.clicked.connect(self.btn2_click)
def btn_click(self):
self.t.start()
def btn2_click(self):
self.btn2.setEnabled(False)
self.t2.start()
if __name__ == '__main__':
import sys
app=QApplication(sys.argv)
win=Window()
win.show()
sys.exit(app.exec_())
import threading
import time
class Task(threading.Thread):
def __init__(self):
super(Task, self).__init__()
self._stop_event = threading.Event()
def run(self):
while not self._stop_event.is_set():
print('hello')
def stop(self):
self._stop_event.set()
t=Task()
t.start()
time.sleep(5)
t.stop()