QWebEngineView - Javascript回调

Question

我最终想要完成的是捕获用户输入到网站的用户名和密码。例如，如果用户在Facebook的登录中输入"test@example.com“作为电子邮件地址，然后单击提交，我想将该电子邮件地址存储在我的PyQt应用程序中。

我最接近实现这一点的方法是使用一系列JavaScript命令将一个侦听器放在"Login Button“上，该按钮返回用户参数的当前值。我的问题是，PyQt提供的回调是在runJavaScript函数完成时进行的，而不是javascript事件侦听器。我想知道是否有任何方法可以从JavaScript函数中捕获回调函数，或者是否有更好的方法来实现这一点。

import os
import sys
from PyQt5.QtWidgets import QApplication, QVBoxLayout, QWidget
from PyQt5.QtCore import QUrl, QEventLoop
from PyQt5.QtWebEngineWidgets import QWebEngineView

class WebPage(QWebEngineView):
    def __init__(self):
        QWebEngineView.__init__(self)
        self.load(QUrl("https://facebook.com"))
        self.loadFinished.connect(self._on_load_finished)
        #self.page().runJavaScript("document.getElementById("myBtn").addEventListener("click", displayDate)", print)

    def _on_load_finished(self):
        print("Finished Loading")
        cmds = ["btn=document.getElementById('u_0_r')",  # Login Button
                "user=document.getElementsByName('email')[0]",
                "function get_username(){return user.value}",
                "btn.addEventListener('click', get_username)"]
        self.page().runJavaScript("; ".join(cmds), lambda x: print("test: %s"  % x))

if __name__ == "__main__":
    app = QApplication(sys.argv)
    web = WebPage()
    web.show()
    sys.exit(app.exec_())  # only need one app, one running event loop

Answer 1

到目前为止，我发现了一个使用"urlChanged“信号的变通方法，它似乎对我的应用程序有效

import os
import sys
from PyQt5.QtWidgets import QApplication, QVBoxLayout, QWidget
from PyQt5.QtCore import QUrl, QEventLoop
from PyQt5.QtWebEngineWidgets import QWebEngineView
from PyQt5.QtWebEngineCore import QWebEngineUrlRequestInterceptor

class WebPage(QWebEngineView):
    def __init__(self):
        QWebEngineView.__init__(self)
        self.current_url = ''
        self.load(QUrl("https://facebook.com"))
        self.loadFinished.connect(self._on_load_finished)
        self.urlChanged.connect(self._on_url_change)

    def _on_load_finished(self):
        self.current_url = self.url().toString()

    def _on_url_change(self):
        self.page().runJavaScript("document.getElementsByName('email')[0].value", self.store_value)

    def store_value(self, param):
        self.value = param
        print("Param: " +str(param))

if __name__ == "__main__":
    app = QApplication(sys.argv)
    web = WebPage()
    web.show()
    sys.exit(app.exec_())  # only need one app, one running event loop