请解释这段代码:def __init__(self): QThread.__init__(self) self.stopped = True self.processing = False self.isCheckVideo = False self.face_cascade = cv2.CascadeClassifier(CASCADE_FILE) self.init_known_face()
时间: 2023-06-06 13:08:16 浏览: 48
这是一段Python的代码,用于初始化一个类(class)。在初始化方法(__init__)中,首先调用了QThread类的初始化方法,并将self传递进去。然后将stopped、processing和isCheckVideo三个变量的值都设置为False。接着使用cv2.CascadeClassifier()方法加载了一个分类器文件(CASCADE_FILE),用于检测视频帧中的人脸。最后调用了一个自定义的init_known_face()方法,用于初始化已知的人脸特征。
相关问题
def run(self): while not self.stopped: try: data = self.serial.read(1) except: continue if data: self.data_received.emit(data)这段代码报错 while not self.stopped: AttributeError: 'SerialThread' object has no attribute 'stopped'
这个错误提示说明在 `SerialThread` 类中没有名为 `stopped` 的属性。这可能是因为你在代码中没有定义这个属性,或者是因为你使用了错误的属性名,或者是因为你尚未初始化 `stopped` 属性。你需要确保在类中定义了 `stopped` 属性,并在初始化函数中对其进行初始化。例如:
```
class SerialThread(QThread):
def __init__(self):
super().__init__()
self.stopped = False
# 其他初始化代码
def run(self):
while not self.stopped:
# 其他代码
```
在这个示例中,我们在 `__init__` 函数中初始化了 `stopped` 属性,并将其设为 False。这样,当 `run` 函数开始运行时,它会检查 `stopped` 属性是否为 False,如果是,则继续执行循环体内的代码。
class MainWindow(QMainWindow): def init(self, user_id): super().init() self.user_id = user_id self.initUI() # 打开串口 self.ser = serial.Serial('COM7', 9600, timeout=1) def initUI(self): # 创建用于显示员工信息的控件 self.info_label = QLabel("员工信息", self) self.info_label.move(100, 50) self.info_label.setStyleSheet("font-size: 24px; color: black; background-color: #eee; border-radius: 10px;") self.id_label = QLabel("员工ID:", self) self.id_label.move(70, 100) self.id_label.setStyleSheet("font-size: 18px; color: black;") self.name_label = QLabel("姓名:", self) self.name_label.move(70, 150) self.name_label.setStyleSheet("font-size: 18px; color: black;") self.six_label = QLabel("性别:", self) self.six_label.move(70, 200) self.six_label.setStyleSheet("font-size: 18px; color: black;") self.sfz_label = QLabel("身份证:", self) self.sfz_label.move(70, 250) self.sfz_label.setStyleSheet("font-size: 18px; color: black;") self.tel_label = QLabel("电话:", self) self.tel_label.move(70, 300) self.tel_label.setStyleSheet("font-size: 18px; color: black;") self.setFixedSize(800, 500) self.setWindowTitle('员工信息') # 查询员工信息 def query_employee(self, id): conn = pymysql.connect(host='39.99.214.172', user='root', password='Solotion.123', database='jj_tset') cursor = conn.cursor() cursor.execute("SELECT * FROM employee_table WHERE user_id='%s'" % id) result = cursor.fetchone() conn.close() return result # 读取数据 def read_data(self): data = self.ser.readline() if data: # 解析数据 id = data.decode().strip() # 查询员工信息 result = self.query_employee(id) if result: # 更新UI界面 self.id_label.setText("员工ID:" + result[0]) self.name_label.setText("姓名:" + str(result[1])) self.six_label.setText("性别:" + result[2]) self.sfz_label.setText("身份证:" + str(result[3])) self.tel_label.setText("电话:" + result[4]) print(result[0],result[1],result[2],result[3],result[4]) else: # 显示空白信息 self.id_label.setText("员工ID:") self.name_label.setText("姓名:") self.six_label.setText("性别:") self.sfz_label.setText("身份证:") self.tel_label.setText("电话:") # 定时读取数据 QTimer.singleShot(100, self.read_data) def closeEvent(self, event): # 关闭串口 self.ser.close()用多线程改写代码,防止主线程阻塞
Here's an example of how you could use multithreading to prevent the main thread from blocking:
```python
from PyQt5.QtCore import Qt, QThread, QTimer, pyqtSignal
class SerialThread(QThread):
dataReceived = pyqtSignal(str)
def __init__(self, parent=None):
super().__init__(parent)
self.ser = serial.Serial('COM7', 9600, timeout=1)
self.running = False
def run(self):
self.running = True
while self.running:
data = self.ser.readline().decode().strip()
if data:
self.dataReceived.emit(data)
def stop(self):
self.running = False
self.wait()
self.ser.close()
class MainWindow(QMainWindow):
def __init__(self, user_id):
super().__init__()
self.user_id = user_id
self.initUI()
self.serialThread = SerialThread(self)
self.serialThread.dataReceived.connect(self.handle_data)
self.serialThread.start()
def initUI(self):
# Create UI elements here
def handle_data(self, data):
# Handle incoming data here
result = self.query_employee(data)
if result:
self.id_label.setText("员工ID:" + result[0])
self.name_label.setText("姓名:" + str(result[1]))
self.six_label.setText("性别:" + result[2])
self.sfz_label.setText("身份证:" + str(result[3]))
self.tel_label.setText("电话:" + result[4])
print(result[0],result[1],result[2],result[3],result[4])
else:
self.id_label.setText("员工ID:")
self.name_label.setText("姓名:")
self.six_label.setText("性别:")
self.sfz_label.setText("身份证:")
self.tel_label.setText("电话:")
def query_employee(self, id):
# Query employee information from database
pass
def closeEvent(self, event):
self.serialThread.stop()
```
In this example, a `SerialThread` is created to handle the serial communication. The `dataReceived` signal is emitted whenever new data is available. The `handle_data` method is called whenever the signal is emitted, and this method updates the UI with the relevant employee information. The `SerialThread` is started in the `MainWindow` constructor, and stopped in the `closeEvent` method.