如何从一个函数将数据插入PyQt5中的多个小部件中

Question

我的接口连接了一个设备，并希望将数据插入QlineEdit小部件

此功能def getdevice_data(self):从设备接收数据并将其作为字符串返回

使用self.get_output__button.clicked.connect(self.getdevice_data)我“启动”功能

并使用self.custom_attribute.connect(self.device_input1.setText)将输出发送到QLineEdit小部件

如何保持功能运行并将功能中的新数据插入到空行编辑小部件中，而无需添加多个按钮来一次又一次地启动该功能？

完整代码

import sys
from PyQt5 import QtWidgets as qtw
from PyQt5 import QtCore as qtc
from PyQt5 import QtGui as qtg

import serial
import time


class CustmClass(qtw.QWidget):
    '''
    description einfügen
    '''

    # Attribut Signal
    custom_attribute = qtc.pyqtSignal(str)

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        # your code will go here


        # Interface
        self.resize(300, 210)
        # button
        self.get_output__button = qtw.QPushButton("start function ?")
        # lineEdit
        self.device_input1 = qtw.QLineEdit()
        self.device_input2 = qtw.QLineEdit()
        # Layout
        vboxlaout = qtw.QVBoxLayout()
        vboxlaout.addWidget(self.get_output__button)
        vboxlaout.addWidget(self.device_input1)
        vboxlaout.addWidget(self.device_input2)

        self.setLayout(vboxlaout)


        self.show()

        # Funktionalität

        self.get_output__button.clicked.connect(self.getdevice_data)

        self.custom_attribute.connect(self.device_input1.setText)
        # self.custom_attribute.connect(self.device_input2.setText)

    def getdevice_data(self):
        try:
            # Serial() opens a serial port
            my_serial = serial.Serial(port='COM6', baudrate=2400, bytesize=7,
                                      parity=serial.PARITY_NONE, timeout=None, stopbits=1)

            if my_serial.is_open:  
                print("port open")
                # log einfügen
                while my_serial.is_open:  

                    data = my_serial.read()  # wait forever till data arives
                    time.sleep(1)  # delay 

                    data_left = my_serial.inWaiting()  
                    data += my_serial.read(data_left)  

                    data = data.decode("utf-8", "strict")

                    if type(data) == str:
                        print(data)
                        return self.custom_attribute.emit(data)
            else:
                print("zu")

        except serial.serialutil.SerialException:
            print("not open")
            # logger hinzufügen


if __name__ == '__main__':
    app = qtw.QApplication(sys.argv)
    w = CustmClass()
    sys.exit(app.exec_())

Answer 1

您不应该在主线程中执行耗时或耗时的循环，因为它们会阻塞事件循环。您要做的是在辅助线程上执行它，并通过信号发送信息。要顺序获取数据，您可以创建一个迭代器并通过next（）函数访问每个元素。

import sys
import threading
import time

import serial

from PyQt5 import QtWidgets as qtw
from PyQt5 import QtCore as qtc
from PyQt5 import QtGui as qtg


class SerialWorker(qtw.QObject):
    dataChanged = qtw.pyqtSignal(str)

    def start(self):
        threading.Thread(target=self._execute, daemon=True).start()

    def _execute(self):
        try:
            my_serial = serial.Serial(
                port="COM6",
                baudrate=2400,
                bytesize=7,
                parity=serial.PARITY_NONE,
                timeout=None,
                stopbits=1,
            )
            while my_serial.is_open:
                data = my_serial.read()  # wait forever till data arives
                time.sleep(1)  # delay
                data_left = my_serial.inWaiting()
                data += my_serial.read(data_left)
                data = data.decode("utf-8", "strict")
                print(data)
                self.dataChanged.emit(data)
        except serial.serialutil.SerialException:
            print("not open")


class Widget(qtw.QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.resize(300, 210)
        self.get_output__button = qtw.QPushButton("start function ?")
        self.device_input1 = qtw.QLineEdit()
        self.device_input2 = qtw.QLineEdit()
        # Layout
        vboxlaout = qtw.QVBoxLayout(self)
        vboxlaout.addWidget(self.get_output__button)
        vboxlaout.addWidget(self.device_input1)
        vboxlaout.addWidget(self.device_input2)

        self.serial_worker = SerialWorker()

        self.device_iterator = iter([self.device_input1, self.device_input2])

        self.get_output__button.clicked.connect(self.serial_worker.start)
        self.serial_worker.dataChanged.connect(self.on_data_changed)

    @qtw.pyqtSlot(str)
    def on_data_changed(self, data):
        try:
            device = next(self.device_iterator)
            device.setText(data)
        except StopIteration:
            pass


if __name__ == "__main__":
    app = qtw.QApplication(sys.argv)
    w = CustmClass()
    w.show()
    sys.exit(app.exec_())