python GUI库图形界面开发之PyQt5中QWebEngineView内嵌网页与Python的数据交互传参详细方法实例

这几天研究了下PyQt5中QWebEngineView内嵌网页与Python的数据交互，今天把实例方法与代码发布出来供大家参数

数据交互需要load进一个网页，这里我选择load进一个本地html网页：JSTest.html。

同时，QWebEngineView与外面的交互还需要Qt官方提供的一个js文件：qwebchannel.js，这个文件可以在网上下载。

JSTest.html和qwebchannel.js两个文件放在同一个目录下，我这边都是放在Python工程目录下。

qwebchannel.js：

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**  * Redistributions of source code must retain the above copyright
**   notice, this list of conditions and the following disclaimer.
**  * Redistributions in binary form must reproduce the above copyright
**   notice, this list of conditions and the following disclaimer in
**   the documentation and/or other materials provided with the
**   distribution.
**  * Neither the name of The Qt Company Ltd nor the names of its
**   contributors may be used to endorse or promote products derived
**   from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
"use strict";

var QWebChannelMessageTypes = {
 signal: 1,
 propertyUpdate: 2,
 init: 3,
 idle: 4,
 debug: 5,
 invokeMethod: 6,
 connectToSignal: 7,
 disconnectFromSignal: 8,
 setProperty: 9,
 response: 10,
};

var QWebChannel = function(transport, initCallback)
{
 if (typeof transport !== "object" || typeof transport.send !== "function") {
   console.error("The QWebChannel expects a transport object with a send function and onmessage callback property." +
          " Given is: transport: " + typeof(transport) + ", transport.send: " + typeof(transport.send));
   return;
 }

var channel = this;
 this.transport = transport;

this.send = function(data)
 {
   if (typeof(data) !== "string") {
     data = JSON.stringify(data);
   }
   channel.transport.send(data);
 }

this.transport.onmessage = function(message)
 {
   var data = message.data;
   if (typeof data === "string") {
     data = JSON.parse(data);
   }
   switch (data.type) {
     case QWebChannelMessageTypes.signal:
       channel.handleSignal(data);
       break;
     case QWebChannelMessageTypes.response:
       channel.handleResponse(data);
       break;
     case QWebChannelMessageTypes.propertyUpdate:
       channel.handlePropertyUpdate(data);
       break;
     default:
       console.error("invalid message received:", message.data);
       break;
   }
 }

this.execCallbacks = {};
 this.execId = 0;
 this.exec = function(data, callback)
 {
   if (!callback) {
     // if no callback is given, send directly
     channel.send(data);
     return;
   }
   if (channel.execId === Number.MAX_VALUE) {
     // wrap
     channel.execId = Number.MIN_VALUE;
   }
   if (data.hasOwnProperty("id")) {
     console.error("Cannot exec message with property id: " + JSON.stringify(data));
     return;
   }
   data.id = channel.execId++;
   channel.execCallbacks[data.id] = callback;
   channel.send(data);
 };

this.objects = {};

this.handleSignal = function(message)
 {
   var object = channel.objects[message.object];
   if (object) {
     object.signalEmitted(message.signal, message.args);
   } else {
     console.warn("Unhandled signal: " + message.object + "::" + message.signal);
   }
 }

this.handleResponse = function(message)
 {
   if (!message.hasOwnProperty("id")) {
     console.error("Invalid response message received: ", JSON.stringify(message));
     return;
   }
   channel.execCallbacks[message.id](message.data);
   delete channel.execCallbacks[message.id];
 }

this.handlePropertyUpdate = function(message)
 {
   for (var i in message.data) {
     var data = message.data[i];
     var object = channel.objects[data.object];
     if (object) {
       object.propertyUpdate(data.signals, data.properties);
     } else {
       console.warn("Unhandled property update: " + data.object + "::" + data.signal);
     }
   }
   channel.exec({type: QWebChannelMessageTypes.idle});
 }

this.debug = function(message)
 {
   channel.send({type: QWebChannelMessageTypes.debug, data: message});
 };

channel.exec({type: QWebChannelMessageTypes.init}, function(data) {
   for (var objectName in data) {
     var object = new QObject(objectName, data[objectName], channel);
   }
   // now unwrap properties, which might reference other registered objects
   for (var objectName in channel.objects) {
     channel.objects[objectName].unwrapProperties();
   }
   if (initCallback) {
     initCallback(channel);
   }
   channel.exec({type: QWebChannelMessageTypes.idle});
 });
};

function QObject(name, data, webChannel)
{
 this.__id__ = name;
 webChannel.objects[name] = this;

// List of callbacks that get invoked upon signal emission
 this.__objectSignals__ = {};

// Cache of all properties, updated when a notify signal is emitted
 this.__propertyCache__ = {};

var object = this;

// ----------------------------------------------------------------------

this.unwrapQObject = function(response)
 {
   if (response instanceof Array) {
     // support list of objects
     var ret = new Array(response.length);
     for (var i = 0; i < response.length; ++i) {
       ret[i] = object.unwrapQObject(response[i]);
     }
     return ret;
   }
   if (!response
     || !response["__QObject*__"]
     || response.id === undefined) {
     return response;
   }

var objectId = response.id;
   if (webChannel.objects[objectId])
     return webChannel.objects[objectId];

if (!response.data) {
     console.error("Cannot unwrap unknown QObject " + objectId + " without data.");
     return;
   }

var qObject = new QObject( objectId, response.data, webChannel );
   qObject.destroyed.connect(function() {
     if (webChannel.objects[objectId] === qObject) {
       delete webChannel.objects[objectId];
       // reset the now deleted QObject to an empty {} object
       // just assigning {} though would not have the desired effect, but the
       // below also ensures all external references will see the empty map
       // NOTE: this detour is necessary to workaround QTBUG-40021
       var propertyNames = [];
       for (var propertyName in qObject) {
         propertyNames.push(propertyName);
       }
       for (var idx in propertyNames) {
         delete qObject[propertyNames[idx]];
       }
     }
   });
   // here we are already initialized, and thus must directly unwrap the properties
   qObject.unwrapProperties();
   return qObject;
 }

this.unwrapProperties = function()
 {
   for (var propertyIdx in object.__propertyCache__) {
     object.__propertyCache__[propertyIdx] = object.unwrapQObject(object.__propertyCache__[propertyIdx]);
   }
 }

function addSignal(signalData, isPropertyNotifySignal)
 {
   var signalName = signalData[0];
   var signalIndex = signalData[1];
   object[signalName] = {
     connect: function(callback) {
       if (typeof(callback) !== "function") {
         console.error("Bad callback given to connect to signal " + signalName);
         return;
       }

object.__objectSignals__[signalIndex] = object.__objectSignals__[signalIndex] || [];
       object.__objectSignals__[signalIndex].push(callback);

if (!isPropertyNotifySignal && signalName !== "destroyed") {
         // only required for "pure" signals, handled separately for properties in propertyUpdate
         // also note that we always get notified about the destroyed signal
         webChannel.exec({
           type: QWebChannelMessageTypes.connectToSignal,
           object: object.__id__,
           signal: signalIndex
         });
       }
     },
     disconnect: function(callback) {
       if (typeof(callback) !== "function") {
         console.error("Bad callback given to disconnect from signal " + signalName);
         return;
       }
       object.__objectSignals__[signalIndex] = object.__objectSignals__[signalIndex] || [];
       var idx = object.__objectSignals__[signalIndex].indexOf(callback);
       if (idx === -1) {
         console.error("Cannot find connection of signal " + signalName + " to " + callback.name);
         return;
       }
       object.__objectSignals__[signalIndex].splice(idx, 1);
       if (!isPropertyNotifySignal && object.__objectSignals__[signalIndex].length === 0) {
         // only required for "pure" signals, handled separately for properties in propertyUpdate
         webChannel.exec({
           type: QWebChannelMessageTypes.disconnectFromSignal,
           object: object.__id__,
           signal: signalIndex
         });
       }
     }
   };
 }

/**
  * Invokes all callbacks for the given signalname. Also works for property notify callbacks.
  */
 function invokeSignalCallbacks(signalName, signalArgs)
 {
   var connections = object.__objectSignals__[signalName];
   if (connections) {
     connections.forEach(function(callback) {
       callback.apply(callback, signalArgs);
     });
   }
 }

this.propertyUpdate = function(signals, propertyMap)
 {
   // update property cache
   for (var propertyIndex in propertyMap) {
     var propertyValue = propertyMap[propertyIndex];
     object.__propertyCache__[propertyIndex] = propertyValue;
   }

for (var signalName in signals) {
     // Invoke all callbacks, as signalEmitted() does not. This ensures the
     // property cache is updated before the callbacks are invoked.
     invokeSignalCallbacks(signalName, signals[signalName]);
   }
 }

this.signalEmitted = function(signalName, signalArgs)
 {
   invokeSignalCallbacks(signalName, signalArgs);
 }

function addMethod(methodData)
 {
   var methodName = methodData[0];
   var methodIdx = methodData[1];
   object[methodName] = function() {
     var args = [];
     var callback;
     for (var i = 0; i < arguments.length; ++i) {
       if (typeof arguments[i] === "function")
         callback = arguments[i];
       else
         args.push(arguments[i]);
     }

webChannel.exec({
       "type": QWebChannelMessageTypes.invokeMethod,
       "object": object.__id__,
       "method": methodIdx,
       "args": args
     }, function(response) {
       if (response !== undefined) {
         var result = object.unwrapQObject(response);
         if (callback) {
           (callback)(result);
         }
       }
     });
   };
 }

function bindGetterSetter(propertyInfo)
 {
   var propertyIndex = propertyInfo[0];
   var propertyName = propertyInfo[1];
   var notifySignalData = propertyInfo[2];
   // initialize property cache with current value
   // NOTE: if this is an object, it is not directly unwrapped as it might
   // reference other QObject that we do not know yet
   object.__propertyCache__[propertyIndex] = propertyInfo[3];

if (notifySignalData) {
     if (notifySignalData[0] === 1) {
       // signal name is optimized away, reconstruct the actual name
       notifySignalData[0] = propertyName + "Changed";
     }
     addSignal(notifySignalData, true);
   }

Object.defineProperty(object, propertyName, {
     configurable: true,
     get: function () {
       var propertyValue = object.__propertyCache__[propertyIndex];
       if (propertyValue === undefined) {
         // This shouldn't happen
         console.warn("Undefined value in property cache for property \"" + propertyName + "\" in object " + object.__id__);
       }

return propertyValue;
     },
     set: function(value) {
       if (value === undefined) {
         console.warn("Property setter for " + propertyName + " called with undefined value!");
         return;
       }
       object.__propertyCache__[propertyIndex] = value;
       webChannel.exec({
         "type": QWebChannelMessageTypes.setProperty,
         "object": object.__id__,
         "property": propertyIndex,
         "value": value
       });
     }
   });

}

// ----------------------------------------------------------------------

data.methods.forEach(addMethod);

data.properties.forEach(bindGetterSetter);

data.signals.forEach(function(signal) { addSignal(signal, false); });

for (var name in data.enums) {
   object[name] = data.enums[name];
 }
}

//required for use with nodejs
if (typeof module === 'object') {
 module.exports = {
   QWebChannel: QWebChannel
 };
}

Python主函数代码

import sys
import Web_UI
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtCore import QObject,pyqtProperty
from PyQt5.QtWebChannel import QWebChannel
from MySharedObject import MySharedObject
from PyQt5.QtWidgets import QApplication
import os

BASE_DIR = os.path.dirname(__file__)#获取当前文件夹的绝对路径

if __name__ == '__main__':
 app = QtWidgets.QApplication(sys.argv)
 MainWindow = QtWidgets.QFrame()
 ui = Web_UI.Ui_Form()
 ui.setupUi(MainWindow)
 ui.webView1.load(QtCore.QUrl(r""+BASE_DIR+"/JSTest.html"))

channel = QWebChannel() ##创建一个QwebChannel对象，用于传递PyQt的参数到JavaScript
 myObj = MySharedObject()
 print(myObj.strval)

channel.registerObject('bridge', myObj)
 ui.webView1.page().setWebChannel(channel)

MainWindow.show()
 sys.exit(app.exec_())

继承了QWidget类的MySharedObject(Python文件)

from PyQt5.QtCore import QObject
from PyQt5.QtCore import pyqtProperty
from PyQt5.QtWidgets import QWidget,QMessageBox

class MySharedObject(QWidget):
 def __init__(self,strval = '100'):
   super(MySharedObject,self).__init__()
   self.strval = strval
 def _getStrValue(self):
   return self.strval
 def _setStrValue(self,str):
   self.strval = str
   print('获得页面参数：％s'％ str)
   QMessageBox.information(self,"Infomation", '获得的页面参数％s' ％ str)
 #需要定义的对外发布的方法
 strValue= pyqtProperty(str,_getStrValue,_setStrValue)

页面代码HTML

<!DOCTYPE html>
   <html>
     <head>
       <meta charset="UTF-8">
       <title>A Demo Page</title>
       <script src = "qwebchannel.js"></script>

<script language = "javascript">
         function completeAndReturnName(){
           var fname = document.getElementById('fname').value;
           var lname = document.getElementById('lname').value;
           var fullname = fname +' '+ lname;

document.getElementById('fullname').value = fullname;
           document.getElementById('submit-btn').style.display = 'block';
           return fullname;
         }
         document.addEventListener("DOMContentLoaded",function(){
           new QWebChannel(qt.webChannelTransport, function (channel) {
             //alert('111 chanel='+channel)
             window.bridge = channel.objects.bridge;
             alert('bridge='+bridge.strValue +'\n从pyqt传来的参数='+window.bridge.strValue);
             //alert('111 chanel='+ channel.objects.strValue)
           })
         } )
         function onShowMsgBox() {
           if(window.bridge != null){
             var fname = document.getElementById('fname').value;
             window.bridge.strValue = fname; //调用对象
           }
         }
       </script>
     </head>

<body>
       <form>
         <label id = "name">User Name:</label>
         <input type = "text" name = "fname" id = "fname"></input>
         <br />
         <input type = "button" value="传递参数到pyqt" οnclick="onShowMsgBox()"></input>
         <br />
         <input type = "reset" value="重置"></input>

</form>
     </body>
   </html>

实现效果

本文详细介绍了PyQt5中使用QWebEngineView控件内嵌网页与Python的数据交互的方法与实例，更多关于这方面的知识请查看下面的相关链接

来源：https://blog.csdn.net/kaida1234/article/details/80422704