firebreath chrome extension: form saver

Question

I have coded a browser helper object in C# for IE, and would like to wrap up that code to implement a chrome/firefox extension. My research led me to Firebreath. I am now loading a content_script file which will fire an onSubmit event and send a message to backgound.htm,js files which handles my firebreath plugin. However, sure enough, m_host now points to the background htm file rather than the original website (from which the user pressed submit button). I tried replacing the html code form the native plugin, but it is not working..

test setup:

content_script:

document.addEventListener('DOMContentLoaded', function () {
alert(document.forms.length);
for (var i = 0; i < document.forms.length; i++) {
    document.forms[i].addEventListener("submit", function () {
        var documentHTML = "<html>" + document.documentElement.innerHTML + "</html>";
        chrome.runtime.sendMessage({ inputElement: documentHTML }, function (response) {        }); }); } });

background.js:

chrome.runtime.onMessage.addListener(
   function (request, sender, sendResponse) {
     document.getElementById('plugin0').sethtml(request.inputElement); });

firebreath code:

void coolnewtestpluginAPI::setInnerHTML(const FB::variant& innerHTML)
{
    m_host->getDOMDocument()->setInnerHTML(innerHTML.convert_cast<std::string>());
}

The native plugin is being called, and I can debug through it. "setInnerHTML()" returns successfully without any errors, but the html code is not being updated, and refers to the original background.htm file. Any ideas?

PS: I'm not that fluent in javascript, so I'd rather offload as much as possible to c# / c++

In case you're not aware, Chrome plans to remove NPAPI support by the end of the year, so this Chrome extension has a very limited lifespan. — smorgan
would using chrome.runtime.sendNativeMessage or chrome.runtime.connectNative be a better option then? I would then probably send individual input elements to the native code from which I'll load my c# library.. — user2707674

taxilian taxilian · Accepted Answer · 2014-04-16T02:31:35

The only way to put an NPAPI/FireBreath plugin into the actual page is to inject the object tag into that page using javascript from the extension. Otherwise the plugin will know nothing about that page.

firebreath chrome extension: form saver

1 Answers