Chrome extension WebNavigation API getFrame - google-chrome

Question

I found a chrome extension WebNavigation API, but I don't know how to use it. Could someone give me a simple example?
API:
chrome.webNavigation.getFrame(object details, function callback)
If I want to get iframe id and iframe's scr in a page, can I use this API ??

Answer 1

As the docs state, one needs to pass tabId, processId, frameId...
in order to get these values, one needs to listen for .onCompleted():
chrome.webNavigation.onCompleted.addListener(function(e){
chrome.webNavigation.getFrame(
{tabId: e.tabId, processId: e.processId, frameId: e.frameId},
function(details){
console.dir(details);
}
);
});
The event's properties are already known before the .getFrame()

Answer 2

If you want to access page content you should use content scripts
So, for example in the manifest.json:
{
"name": "My extension",
...
"content_scripts": [
{
"matches": ["http://www.example.com/*"],
"js": ["jquery.js", "myscript.js"]
}
],
}
And in myscript.js:
var iframe = document.querySelector('iframe');
alert(iframe.getAttribute('id'), iframe.getAttribute('src'));
Another way is to use programmatic injection which is in fact simplified content scripting.
Update:
To get src from all iframes on the page:
var iframes = document.querySelectorAll('iframe');
for(var i = 0; i < iframes.length; i++){
console.log(iframes[i].getAttribute('id'), iframes[i].getAttribute('src'));
}