是否可以从QWebView中的JavaScript调用C ++函数？ [英] Is it possible to call a C++ function from JavaScript in a QWebView?

问题描述

我有一个网页加载在QWebView。在那里，我想有一个JavaScript调用我的应用程序的函数。该函数将返回JavaScript将动态显示的一些字符串。

I have a web page loaded in a QWebView. In there, I would like to have JavaScript call a function of my application. That function would then returns some strings that JavaScript would dynamically display.

可以使用QWebView吗？基本上，是否可能在应用程序（在C ++中）和QWebView控件之间有一些桥梁？

Can it be done using QWebView? Basically, is it possible to have some bridge between the application (in C++) and the QWebView control?

推荐答案

最终做到了。我在我的头文件中用 Q_INVOKABLE 方法声明了一个JavaScriptBridge类。 Q_INVOKABLE 方法可以从JavaScript调用：

This is how I ended up doing it. I declared a "JavaScriptBridge" class in my header file with a Q_INVOKABLE method. Q_INVOKABLE methods can be called from JavaScript:

class DictionaryJavaScriptBridge : public QObject {

    Q_OBJECT

public:

    DictionaryJavaScriptBridge(DictionaryWidget* dictionaryWidget); 
    Q_INVOKABLE QStringList sentences(QString characters);

private:

    DictionaryWidget* dictionaryWidget_;

};

然后在我的.cpp文件中创建桥：

Then in my .cpp file, I create the bridge:

jsBridge_ = new DictionaryJavaScriptBridge(this);

我听到 javaScriptWindowObjectCleared 信号。这一步很重要，因为WebKit将在加载新页面时清除所有JavaScript对象，因此您需要每次都添加回桥：

And I listen to the javaScriptWindowObjectCleared signal. This step is important because WebKit is going to clear all the JavaScript objects when loading a new page, so you need to add back the bridge every time:

connect(ui->webView->page()->mainFrame(), SIGNAL(javaScriptWindowObjectCleared()), this, SLOT(mainFrame_javaScriptWindowObjectCleared()));

最后，在 javaScriptWindowObjectCleared 添加JavaScript桥：

Finally, in the javaScriptWindowObjectCleared slot, I add the JavaScript bridge:

void DictionaryWidget::mainFrame_javaScriptWindowObjectCleared() {
    ui->webView->page()->mainFrame()->addToJavaScriptWindowObject("ehbridge", jsBridge_);
}

现在从JavaScript开始，会出现一个全局的ehbridge对象。我可以像一个普通的JavaScript对象（Qt将Qt的类型转换为JavaScript类型）来调用它的方法。

Now from JavaScript, there will be a global "ehbridge" object exposed. I can call its methods like a normal JavaScript object (Qt converts Qt's types to JavaScript types)

var sentences = ehbridge.sentences("test");

这篇关于是否可以从QWebView中的JavaScript调用C ++函数？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！