实现本地QObject和JavaScript交互

Qt本地对象和JavaScript交互分为三个步骤将本地QObject暴露给webkit和JavaScript将本地QObject的信号和JavaScript的槽连接起来通过JavaScript调用本地QObject的槽也就是第1步和第2步结合起来实现 本地QObject的信号和JavaScript的槽连接 第1步和第3步结合起来实现 通过JavaScript调用本地QObject的槽下面我们就分别看一下第1、2、3步分别如何实现的。1、将本地QObject暴露给Webkit。主要分为以下几个步骤。新建一个QObject， 命名为simpleQObject，包含信号和槽。其头文件如下：#include #include #include #include class SampleQObject : public QObject {Q_OBJECTpublic:SampleQObject(QObject *parent = 0);signals: /* 声明QObject signals */void signal(QMap object);public slots: /*声明 QObject slots */ QMap slotThatReturns(const QMapQVariant>& object); //QObject 的槽，用来返回字符串void slotThatEmitsSignal(); //QObject的槽，用来发射信号，并且记录发射次数private:int m_signalEmited;QMap m_returnObject;QMap m_emitSignal;};创建实现函数。mainwindow.h 和 mainwindow.cpp。 mainwindow.h代码如下#include #include "sampleqobject.h“class MainWindow : public QMainWindow {Q_OBJECTpublic:MainWindow(QWidget *parent = 0);~MainWindow();private slots:/*声明 将 QObject 暴露给 Qt WebKit 的函数*/void addJavaScriptObject();protected:void changeEvent(QEvent *e);private:Ui::MainWindow *ui;SampleQObject* m_sampleQObject;};mainwindow.cpp关键代码如下：//当网页被载入或者刷新时，将暴露给webkit的QObject和webkit JavaScript连接connect(ui->webView->page()->mainFrame(), SIGNAL(javaScriptWindowObjectCleared()),this, SLOT(addJavaScriptObject()));void MainWindow::addJavaScriptObject(){//addJavaScriptObject函数的实现：将simpleQObject和webkit JavaScript连接this->ui->webView->page()->mainFrame()->addToJavaScriptWindowObject("sampleQObject“, this->m_sampleQObject);}2. 将本地QObject的信号和JavaScript的槽连接起来如何发射QObject信号。signals:void signal(QMap object);public slots:void slotThatEmitsSignal();/* this slot is designed to emit signals and count emit times*/void SampleQObject::slotThatEmitsSignal(){qDebug() this->m_signalEmited++; /* count emit times */this->m_emitSignal.clear();this->m_emitSignal["signalsEmited"] = QVariant(this->m_signalEmited);this->m_emitSignal["sender"] = QVariant("SampleQObject::slotThatEmitsSignal");qDebug() m_emitSignal;/* 发射信号 */ emit signal(this->m_emitSignal);}JavaScript槽的实现$(document).ready(function() {try {/* 将sampleQObjects的signal 和 JavaScript slot 连接起来*/sampleQObject.signal.connect(slot);/* 当simpleQObject发射信号时调用JavaScript的槽 */sampleQObject.slotThatEmitsSignal();}catch(e) {alert(e);}});/* slot函数将会输出 SimpleQObject has emited signal ？ times */function slot(object) {var objectString = object.sender + " has emited signal " + object.signalsEmited + " times.";alert(objectString);}Run the app。 当点击刷新时，弹出新的对话框：3. 通过JavaScript调用本地QObject的槽JavaScript信号发射try {var object = {intValue: 1};/* 声明一个JavaScript object并用simpleQObject的槽的返回值赋值它*/var returnedObject = sampleQObject.slotThatReturns(object);/* 输出 "1 added bonus"*/alert(returnedObject.stringValue);}QObject 槽函数QMap SampleQObject::slotThatReturns(const QMap& object){qDebug() this->m_returnObject.clear();this->m_returnObject.unite(object);QString addedBonus = QString::number(object["intValue"].toInt(),10).append(" added bonus.");this->m_returnObject["stringValue"] = QVariant(addedBonus);qDebug() m_returnObject;return this->m_returnObject; // 返回m_returnObject包含有字符串 1 added bonus }Run the app本例子代码下载地址： http://software.intel.com/file/28111 http://software.intel.com/file/28112 注：本例子中部分代码来自wiki.forum.nokia.com http://wiki.forum.nokia.com/index.php/Exposing_QObjects_to_Qt_Webkit下一篇我们将探索一下如何将S60下的web runtime widget porting至Qt的webkit上来，如今的WRT widget只能依赖于S60的os，如果porting只QT的webkit，那么将可以实现广泛开发者梦寐已久的跨平台功能。