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PyQt5中QWebEngineView与JavaScript交互

发表于 更新于

准备工作

开发环境

  • Python 3.8.1
  • Windows 10

安装依赖

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pip install PyQt5
pip install PyQtWebEngine

Python端

  1. 使用QWebChannel的registerObject（"JsBridge名","JsBridge"）方法注册回调

    • JsBridge名：在JavaScript中调用时使用的对象名称
    • JsBridge：被JavaScript调用的Python对象

  2. JsBridge 对象

    • 入参
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    @QtCore.pyqtSlot(str)
    def log(self, message):
        print(message)
    • 出参
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    @QtCore.pyqtSlot(result=str)
    def getName(self):
        return "hello"
    • 出入参
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    @QtCore.pyqtSlot(str, result=str)
    def test(self, message):
        print(message)
        return "ok"

JavaScript端

  1. 在Html的<head>中添加

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    <script src='qrc:///qtwebchannel/qwebchannel.js'></script>

  2. 调用

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    new QWebChannel(qt.webChannelTransport, function(channel) {
         channel.objects.pythonBridge.test("hello",function(arg) {
             console.log("Python message: " + arg);
             alert(arg);
         });
     });

  3. 调试(Chrome DevTools)

    1. 配置环境变量：QTWEBENGINE_REMOTE_DEBUGGING = port
    2. 使用Chromium内核的浏览器打开地址：http://127.0.0.1:port
    3. 使用PyCharm中可以在运行配置(Run/Debug Configurations)中的Environment variables中添加环境变量,用;号分隔，然后可以直接运行。

Demo

Python

  1. JsBridge

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    from PyQt5 import QtCore

    class JsBridge(QtCore.QObject):
        @QtCore.pyqtSlot(str, result=str)
        def test(self, message):
            print(message)
            return "ok"
  2. Application
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    from PyQt5 import QtCore
    from PyQt5 import QtWebEngineWidgets
    from PyQt5.QtCore import QDir
    from PyQt5.QtWebChannel import QWebChannel
    from PyQt5.QtWebEngineWidgets import QWebEngineView
    from PyQt5.QtWidgets import *

    class TestWindow(QMainWindow):
        def __init__(self):
            super().__init__()
            self.webView = QWebEngineView()
            self.webView.settings().setAttribute(
                QtWebEngineWidgets.QWebEngineSettings.JavascriptEnabled, True)

            channel = QWebChannel(self.webView.page())
            self.webView.page().setWebChannel(channel)
            self.python_bridge = JsBridge(None)
            channel.registerObject("pythonBridge", self.python_bridge)
            layout = QVBoxLayout()
            layout.addWidget(self.webView)
            widget = QWidget()
            widget.setLayout(layout)
            self.setCentralWidget(widget)

            self.resize(900, 600)
            self.setWindowTitle('Test')
            qr = self.frameGeometry()
            cp = QDesktopWidget().availableGeometry().center()
            qr.moveCenter(cp)
            self.move(qr.topLeft())
            self.show()
            html_path = QtCore.QUrl.fromLocalFile(QDir.currentPath() + "/assets/index.html")
            self.webView.load(html_path)

    if __name__ == '__main__':
        app = QApplication(sys.argv)
        m = TestWindow()
        sys.exit(app.exec_())

JavaScript

index.html
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<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
    <title>Test</title>
    <script src='qrc:///qtwebchannel/qwebchannel.js'></script>
    <script src="https://code.jquery.com/jquery-3.4.1.min.js"
            integrity="sha256-CSXorXvZcTkaix6Yvo6HppcZGetbYMGWSFlBw8HfCJo="
            crossorigin="anonymous"></script>
</head>
<body>
   <button id="test">test</button>
</body>
<script>
    $(document).ready(function() {
        new QWebChannel(qt.webChannelTransport, function(channel) {
            $('#test').on('click', function() {
                channel.objects.pythonBridge.test("hello",function(arg) {
                  console.log("Python message: " + arg);
                  alert(arg);
                });
            });
        });
    });
</script>
</html>