PyQt5 - Automate Serial module

2019-02-20 13:39发布

问题:

I am trying to automate serial connection without clicking on button. When the gui load, serial should be read immediately and refreshed at interval without using the mouse to trigger any button (that is auto read in and updated).

How possible is this? See script and GUI below..

import schedule
import serial
import sys
from PyQt5 import uic, QtWidgets


qtCreatorFile = "gui.ui" 

Ui_MainWindow, QtBaseClass = uic.loadUiType(qtCreatorFile)

estudiantes = ['   ','    ','     ','    '] 

ser = serial.Serial('COM9', baudrate=9600, timeout=1)

class MyApp(QtWidgets.QMainWindow, Ui_MainWindow):
    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        Ui_MainWindow.__init__(self)
        self.setupUi(self)
        self.Boton.clicked.connect(self.ingresos)
        #self.ingresos()

    def ingresos(self):

        dato = ser.readline().decode('ascii')

        #datos = (self.Box4.toPlainText())
        #dato = str(datos)
        estudiantes.insert(0,dato)
        estudiantes.pop()

        self.Box1.setText(estudiantes[0])
        self.Box2.setText(estudiantes[1])
        self.Box3.setText(estudiantes[2])
        self.Box4.setText(estudiantes[3])
        #self.Box1.setText("estudiantes")

# =============================================
        def job():
            # print("I'm working...")
            dato = ser.readline().decode('ascii')

            #datos = (self.Box4.toPlainText())
            #dato = str(datos)
            estudiantes.insert(0,dato)
            estudiantes.pop()

            self.Box1.setText(estudiantes[0])
            self.Box2.setText(estudiantes[1])
            self.Box3.setText(estudiantes[2])
            self.Box4.setText(estudiantes[3])
            #self.Box1.setText("estudiantes")

        # .......................    

        schedule.every(0.05).minutes.do(job)

        while True:
            schedule.run_pending()
            time.sleep(1)        

# .... Time definition ....
# 0.05 = 05 Seconds
# 0.50 = 50 Seconds
# 5.00 = 05 Minutes

# =============================================




if __name__ == "__main__":
    app =  QtWidgets.QApplication(sys.argv)
    window = MyApp()
    window.show()
    sys.exit(app.exec_()) 

The PyQt5 GUI .ui file is HERE....

回答1:

A basic rule in Qt is that the GUI should not be updated from a thread other than the main one, this is called the GUI thread. There are several options such as sending the data through signals to the main thread, or using a QRunnable with QThreadPool as shown below:

Code:

qtCreatorFile = "gui.ui" 
Ui_MainWindow, QtBaseClass = uic.loadUiType(qtCreatorFile)
estudiantes = ['   ','    ','     ','    '] 

class SerialRunnable(QtCore.QRunnable):
    def __init__(self, w):
        QtCore.QRunnable.__init__(self)
        self.w = w
        self.ser = serial.Serial('COM9', baudrate=9600, timeout=1)

    def run(self):
        while True:
            dato = self.ser.readline().decode('ascii')
            if dato != "":
                QtCore.QMetaObject.invokeMethod(self.w, "setValues",
                                     QtCore.Qt.QueuedConnection,
                                     QtCore.Q_ARG(str, dato))
            QtCore.QThread.msleep(10)


class MyApp(QtWidgets.QMainWindow, Ui_MainWindow):
    def __init__(self):
        QtWidgets.QMainWindow.__init__(self)
        self.setupUi(self)
        runnable = SerialRunnable(self)
        QtCore.QThreadPool.globalInstance().start(runnable)

    @QtCore.pyqtSlot(str)
    def setValues(self, dato):
        estudiantes.insert(0,dato)
        estudiantes.pop()
        self.Box1.setText(estudiantes[0])
        self.Box2.setText(estudiantes[1])
        self.Box3.setText(estudiantes[2])
        self.Box4.setText(estudiantes[3])