python qt5线程不实时刷新控件

时间:2018-07-13 13:56:06

标签: python pyqt5 qthread

我正在使用QT5和python编写UI,我添加了一个处理UI的线程,线程工作“ fine ”,该线程内部的函数接收2个字符串并返回2个字符串(我在开发实际项目之前先进行实验,以了解其工作原理),如下所示,您可以在代码中看到线程函数:

self.requestConexion.emit('lblText1','dddddd')

我调用另一个只是一个简单计数器的函数

self.contador()

因此,我希望在计数器完成控件self.lblText1的值更改之前,但这不会发生...这是主要代码:

from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
import UI_test
import time
import sys

class Threaded(QObject):
    result=pyqtSignal(str,str)
    def __init__(self, parent=None, **kwargs):
        super().__init__(parent, **kwargs)

    @pyqtSlot(str,str)
    def etiquetas(self,lbl,texto):
        print(texto)
        self.result.emit(lbl,texto)


class MainApp(QMainWindow, UI_test.Ui_MainWindow):
    requestConexion=pyqtSignal(str,str)
    def __init__(self, parent=None):
        super(MainApp, self).__init__(parent)
        self._thread=QThread()
        self._threaded=Threaded(result=self.displayLabel)
        self.requestConexion.connect(self._threaded.etiquetas)
        self._threaded.moveToThread(self._thread)
        qApp.aboutToQuit.connect(self._thread.quit)
        self._thread.start()
        self.setupUi(self)
        self.btnStart.clicked.connect(self.conexion)

    @pyqtSlot()
    def conexion(self):
        #self._thread.start()
        print(1)
        self.requestConexion.emit('lblText1','dddddd')
        self.contador()
        text, ok = QInputDialog.getText(self, 'Text Input Dialog', 'Enter your name:')
        if ok:
             print(str(text))

    @pyqtSlot()
    def contador(self):
        i=0
        while i<50:
            print(i)
            time.sleep(0.1)
            i+=1

    @pyqtSlot(str,str)
    def displayLabel(self, etiqueta, texto):
        self.lblText1.setText(etiqueta)
        print(texto)


def main():
    app = QApplication(sys.argv)  
    form = MainApp()                 
    form.show()                         
    app.exec_()                         
    exit(app.exec_())

if __name__ == '__main__':              
    main()

有什么问题吗?

1 个答案:

答案 0 :(得分:0)

我终于在下一个博客中找到了我的问题的答案:

http://www.dba-oracle.com/t_convert_blob_to_xml_type.htm

这是一个非常不错的教程,阅读了博客中的文档后,我能够修改其中一个示例以实时修改标签控件的文本;这是最终代码:

from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
import time

class Worker(QRunnable):
    def __init__(self, fn, *args, **kwargs):
        super(Worker, self).__init__()        
        self.args = args
        self.kwargs = kwargs
        self.fn = fn

    @pyqtSlot()
    def run(self):
        #print(self.args, self.kwargs)
        print("Thread start") 
        time.sleep(0.2)
        self.fn(*self.args, **self.kwargs)  #ejecuta la funcion recibida


class MainWindow(QMainWindow):


    def __init__(self, *args, **kwargs):
        super(MainWindow, self).__init__(*args, **kwargs)

        self.threadpool = QThreadPool()
        print("Multithreading with maximum %d threads" % self.threadpool.maxThreadCount())

        self.counter = 0

        layout = QVBoxLayout()

        self.l = QLabel("Start")
        self.l2 = QLabel("xxxxx")
        b = QPushButton("DANGER!")
        b.pressed.connect(self.oh_no)

        layout.addWidget(self.l)
        layout.addWidget(self.l2)
        layout.addWidget(b)

        w = QWidget()
        w.setLayout(layout)

        self.setCentralWidget(w)

        self.show()

        self.etiqueta="rrrrrrrrrr"

        self.timer = QTimer()
        self.timer.setInterval(500)
        self.timer.timeout.connect(self.recurring_timer)
        self.timer.start()

    def oh_no(self):
        self.etiqueta="hhhhhhhhhhhhhhhhh"
        worker = Worker(self.execute_this_fn,'4444')
        self.threadpool.start(worker)

    def recurring_timer(self):
        self.counter +=1
        self.l.setText("Counter: %d" % self.counter)


    def execute_this_fn(self,x):
        print("Hello!")
        self.l2.setText(x)


app = QApplication([])
window = MainWindow()
app.exec_()