循环时GUI变得无响应

Question

单击按钮后，表单将变得无响应，直到解析函数完成其工作。你知道吗

我想把searchAll函数移到线程。我确实读过几个类似问题的答案，但我不明白怎么读。你知道吗

class MyForm(QDialog):


    def __init__(self):
        super().__init__()
        self.ui = Ui_Dialog()
        self.ui.setupUi(self)
        self.ui.buttonOK.clicked.connect(self.searchAll)
        self.show()

    def searchAll(self):

        sID = self.ui.txtSellerID.text()
        sUrl = "https://removed.com/" + sID + "/p/?section=2&page=1"
        sr = requests.get(sUrl)
        soup1 = BeautifulSoup(sr.text, "html.parser")

        NumberOfPagesBlock = soup1.find_all("li", class_="text-gray")

        if not NumberOfPagesBlock:
            QMessageBox.about(self, "Warning", "Nothing Here")
        else:
            items = re.compile(r'[^\d.]+')
            PagesCount = -(-items // 60)

            for i in range(1, int(PagesCount + 1)):
                itemsIdDs = soup1.find_all("div", class_="large-single-item")

                for itemsIdD in itemsIdDs:
                    iUrl = ("https://removed.com/" + itemsIdDs.get('data-ean') + "/s")
                    r = requests.get(iUrl)
                    soup = BeautifulSoup(r.text, "html.parser")
                    seller = soup.find("div", id="productTrackingParams")
                    title = (str(ctr) + '- ' + "Title " + str(seller.get('data-title')))
                    self.ui.txtDetails.appendPlainText(title)


if __name__ == "__main__":

    app = QApplication(sys.argv)
    w = MyForm()
    w.show()
    sys.exit(app.exec_())

Answer 1

您必须在另一个线程中执行繁重的任务（requests+BeautifulSoup），因为它们会阻塞GUI所在的主线程，从而阻止GUI正常工作，例如，冻结屏幕。在本例中，我将实现工作线程方法：

import re
import ssl
import sys
from functools import partial

import requests
from PyQt5.QtCore import QObject, QThread, QTimer, pyqtSignal, pyqtSlot
from PyQt5.QtWidgets import QApplication, QDialog, QMessageBox
from bs4 import BeautifulSoup

from foo_module import Ui_Dialog


class ScrapeWorker(QObject):
    started = pyqtSignal()
    finished = pyqtSignal()
    resultsChanged = pyqtSignal(str)
    errorSignal = pyqtSignal(str)

    @pyqtSlot(str)
    def run(self, text):
        self.started.emit()
        sUrl = "https://removed.com/{}/p/?section=2&page=1".format(text)
        try:
            sr = requests.get(sUrl)
        except Exception as e:
            self.errorSignal.emit("error: {}".format(e))
            self.finished.emit()
            return
        soup1 = BeautifulSoup(sr.text, "html.parser")
        NumberOfPagesBlock = soup1.find_all("li", class_="text-gray")
        if not NumberOfPagesBlock:
            self.errorSignal.emit("Nothing Here")
        else:
            items = re.compile(r"[^\d.]+")
            PagesCount = -(-items // 60)
            for i in range(1, int(PagesCount + 1)):
                itemsIdDs = soup1.find_all("div", class_="large-single-item")

                for itemsIdD in itemsIdDs:
                    iUrl = "https://removed.com/{}/s".format(itemsIdDs.get("data-ean"))
                    r = requests.get(iUrl)
                    soup = BeautifulSoup(r.text, "html.parser")
                    seller = soup.find("div", id="productTrackingParams")
                    title = "{}- Title {}".format(ctr, seller.get("data-title"))
                    self.resultsChanged.emit(title)
        self.finished.emit()


class MyForm(QDialog):
    def __init__(self):
        super().__init__()
        self.ui = Ui_Dialog()
        self.ui.setupUi(self)
        self.ui.buttonOK.clicked.connect(self.searchAll)

        thread = QThread(self)
        thread.start()

        self.m_worker = ScrapeWorker()
        self.m_worker.moveToThread(thread)
        self.m_worker.started.connect(self.onStarted)
        self.m_worker.finished.connect(self.onFinished)
        self.m_worker.resultsChanged.connect(self.onResultChanged)
        self.m_worker.errorSignal.connect(self.onErrorSignal)

    @pyqtSlot()
    def searchAll(self):
        sID = self.ui.txtSellerID.text()
        wrapper = partial(self.m_worker.run, sID)
        QTimer.singleShot(0, wrapper)

    @pyqtSlot(str)
    def onResultChanged(self, title):
        self.ui.txtDetails.appendPlainText(title)

    @pyqtSlot()
    def onStarted(self):
        self.ui.buttonOK.setEnabled(False)

    @pyqtSlot()
    def onFinished(self):
        self.ui.buttonOK.setEnabled(True)

    @pyqtSlot(str)
    def onErrorSignal(self, message):
        QMessageBox.about(self, "Warning", message)


if __name__ == "__main__":

    app = QApplication(sys.argv)
    w = MyForm()
    w.show()
    sys.exit(app.exec_())