PYQT 与 js 交互
PYQT做图形界面还是没有HTML做的炫，所以将PYQT与静态HTML结合就会有焕然一新的感觉。
HTML文件
<!DOCTYPE html>
<title>QWebChannel交互Demo
<button onclick="sendMes()">发送消息
<p id="mes">
<script type="text/javascript" src="qwebchannel.js">
window.onload = function() {
new QWebChannel(qt.webChannelTransport, function (channel) {
window.printer= channel.objects.printer; // 此处channel.objects.printer中的printer就是上文提到的功能类注册的标识名
});
};
function sendMes() { // 调用python端的功能类的方法执行操作
// var a = printer.print('你收到一条网页发送的消息！')
printer.print('你收到一条网页发送的消息！');
}
function uptext(msg) {
alert(msg);
}
</html>
这里需要加载qwebchannel.js，下面是qwebchannel.js文件
/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2014 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Milian Wolff
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtWebChannel module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, 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 iin 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 objectNamein data) {
var object =new QObject(objectName, data[objectName], channel);
}
// now unwrap properties, which might reference other registered objects
for (var objectNamein 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 (responseinstanceof 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 propertyNamein qObject) {
propertyNames.push(propertyName);
}
for (var idxin 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 propertyIdxin 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 propertyIndexin propertyMap) {
var propertyValue = propertyMap[propertyIndex];
object.__propertyCache__[propertyIndex] = propertyValue;
}
for (var signalNamein 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 namein data.enums) {
object[name] = data.enums[name];
}
}
//required for use with nodejs
if (typeof module ==='object') {
module.exports = {
QWebChannel: QWebChannel
};
}
对应的python文件
#! /usr/bin/env
# -*- coding: utf-8 -*-
# webview.py
from PyQt5.QtWidgetsimport QApplication
from PyQt5.QtCoreimport QObject, pyqtSlot, QUrl
from PyQt5.QtWebChannelimport QWebChannel
from PyQt5.QtWebEngineWidgetsimport QWebEngineView
import sys
class Print(QObject):
# pyqtSlot，中文网络上大多称其为槽。作用是接收网页发起的信号
@pyqtSlot(str, result=str)
def print(self, content):
print(content)# 对接收到的内容进行处理，比如调用打印机进行打印等等。此处略去，只在bash中显示接收到的消息
self.myHello()
return 'python'
@pyqtSlot(result=str)
def myHello(self):
browser.page().runJavaScript('uptext("hello, Python");')
# print('call received')
return 'hello, Python'
if __name__ =='__main__':
app = QApplication(sys.argv)
browser = QWebEngineView()# 新增一个浏览器引擎
browser.setWindowTitle('QWebChannel交互Demo')
browser.resize(900, 600)
channel = QWebChannel()# 增加一个通信中需要用到的频道
printer = Print()# 通信过程中需要使用到的功能类
channel.registerObject('printer', printer)# 将功能类注册到频道中，注册名可以任意，但将在网页中作为标识
browser.page().setWebChannel(channel)# 在浏览器中设置该频道
url_string ="file:///D:/wb/PycharmProjects/wb/index.html" # 内置的网页地址，此处我采用的是本地的。远程同样可以使用。
browser.load(QUrl(url_string))
browser.show()
sys.exit(app.exec_())
效果图是下面：
