PyQt4中QWebView的多线程 [英] multiple threads of QWebView in PyQt4

问题描述

情况如下:我有一个加载特定 url 的类，还有一个参数列表，我需要发送到这个 url.我想使用线程来同时"加载这个 url，换句话说，不是加载一个 QWebView ，而不是加载另一个我想一次打开 5 个窗口的另一个.

Here is the situation: I have a class that loads specific url, also have a list of parameters, that I need to send to this url. I want to use threads to load this url kinda 'simultaneously', in other words in stead of loading one QWebView , than finish it than load another one I want to open 5 windows at a time.

好的，那么现在的问题是，每个窗口的速度都不同，所以我需要跟踪正在使用的参数.

OK, So now the problem is, every single window will have different speed, so I need to keep track of what parametrs are in use.

例如:

params = [1,2,3,4,5,6,7]
a = MyClass(1)
b = MyClass(2)
c = MyClass(3)

现在，如果假设班级 b 在其他 2 个班级之前完成，它将获得值 4，并将重新开始.

now if lets say class b has finished befoure other 2 classes, it will get value 4, and will start it again.

这是示例代码:

#! /usr/bin/env python2.7

from PyQt4.QtCore import *
from PyQt4.QtGui import *
from PyQt4.QtWebKit import *
import sys, signal

class Grabber(QWebView):
    def __init__(self, param=None):
        QWebView.__init__(self)
        self.loadFinished.connect(self._loadComplete)
        url = QUrl('http://some website.com/search?param=%s'%param)
        self.load(url)
        self.show()

    def _loadComplete(self):
        print "Done"

if __name__ == "__main__":
    app = QApplication(sys.argv)
    # Dont know what to do with the next 2 lines
    thread_pool = QThreadPool()
    thread_pool.setMaxThreadCount(10)

    param = [1,2,3,4,5,6,7,8,9,10,11,12] # and so on

    # Whant to achive something similar:
    for i in param:
        a = Grabber(i)
        b = Grabber(i)
        c = Grabber(i)
        d = Grabber(i)
        e = Grabber(i)

    if signal.signal(signal.SIGINT, signal.SIG_DFL):
        sys.exit(app.exec_())
    app.exec_() 

我很确定我需要使用线程、ether python 本地线程或 PyQt4 QThread.

I'm pretty sure I need to use threads, ether python native threads or PyQt4 QThread.

推荐答案

看看这样的事情是否有效.这个bookie 类所做的就是将loadFinished 被调用的次数存入变量count 中，并返回列表中对应的项参数.在创建grabber 对象时，它通过QSignalMapper 将其映射到一个数字，因此您可以通过调用mapper.mapping(id-of-grabber-object).在修改您的代码之前，您可以继续尝试此代码，看看它是否适合您:

See if something like this works. What this bookie class does is store the number of times loadFinished is called into the variable count, and returns the corresponding item in the list params. When creating the grabber objects, it maps it to a number through QSignalMapper, so you may retrieve the sender of the signal by calling mapper.mapping(id-of-grabber-object). You can go ahead and try this code to see if it works for you before modifying yours:

#!/usr/bin/env python
from PyQt4.QtCore import pyqtSlot, QObject, QSignalMapper, QTimer
from PyQt4.QtGui import QApplication
from PyQt4.QtWebKit import QWebView


class bookie(QObject):
    def __init__(self, parent=None):
        super(bookie, self).__init__(parent)

        self.count  = 0
        self.url    = 'http://some website.com/search?param={0}'
        self.params = range(100) # instead of [1,2,3,4,5,6,7,8,9,10,11,12] and so on...

        Grabber = QWebView # This would be your Grabber class

        self.mapper = QSignalMapper(self)
        self.mapper.mapped.connect(self.on_mapper_mapped)

        for grabberNumber in range(10): # Create 10 Grabber instances
            grabber = Grabber()
            grabber.loadFinished.connect(self.mapper.map)

            self.mapper.setMapping(grabber, grabberNumber)

            grabber.loadFinished.emit(True) # Initialize the grabber by emitting loadFinished

    def on_mapper_mapped(self, gNumber):
        self.count += 1
        if self.count < len(self.params):
            gParam  = self.params[self.count]   
            grabber = self.mapper.mapping(gNumber)
            #grabber.load(QUrl(self.url.format(gParam)))

            # Next 2 lines for testing purposes, remove & uncomment the previous line

            print "GRABBER:", gNumber, "PARAMETER:", gParam
            QTimer.singleShot(1, lambda:grabber.loadFinished.emit(True)) 

if __name__ == "__main__":
    import  sys

    app = QApplication(sys.argv)
    main = bookie()

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