Multiple Tab Chrome Extension Issue - google-chrome-extension

Question

I've created a basic extension that searches Google if the URL/HTML content fulfill certain requirements. It works for the most part, but fails miserably when there are multiple instances of the extension. For example, if I load tab A and then tab B, but click on the page action for tab A, I will be directed to a search of tab B's content.
I don't know how to silo the script to each tab, so that clicking tab A's page action will always result in a search for tab A stuff. How can that be done? I'd appreciate your suggestions!
background.js
title = "";
luckySearchURL = "http://www.google.com/search?btnI=I%27m+Feeling+Lucky&ie=UTF-8&oe=UTF-8&q=";
chrome.runtime.onMessage.addListener(
function(request, sender, sendResponse) {
if (request.title != "") {
title = request.title;
sendResponse({confirm: "WE GOT IT."});
}
});
chrome.tabs.onUpdated.addListener(function(tabId, change, tab) {
if (change.status === "complete" && title !== "") {
chrome.pageAction.show(tabId);
}
});
chrome.pageAction.onClicked.addListener(function(tab) {
chrome.tabs.create({url: luckySearchURL + title})
})
contentscript.js
function getSearchContent() {
url = document.URL;
if (url.indexOf("example.com/") > -1)
return "example";
}
if (window === top) {
content = getSearchContent();
if (content !== null) {
chrome.runtime.sendMessage({title: content}, function(response) {
console.log(response.confirm); })
};
}

Answer 1

You could do something like store the title with its associated tabId, that way when you click on the pageAction it uses the correct title. The changes would be just these:
background.js
title= [];
[...]
chrome.runtime.onMessage.addListener(function(request,sender,sendResponse){
if (request.title != "") {
title.push({tabId:sender.tab.id, title:request.title});
sendResponse({confirm: "WE GOT IT."});
}
});
[...]
chrome.pageAction.onClicked.addListener(function(tab) {
title.forEach(function(v,i,a){
if(v.tabId == tab.id){
chrome.tabs.create({url: luckySearchURL + v.title});
// Here I am going to remove it from the array because otherwise the
// array would grow without bounds, but it would be better to remove
// it when the tab is closed so that you can use the pageAction more
// than once.
a.splice(i,1);
}
});
});

Answer 2

You're facing this issue because of window === top. So your title variable gets its value from the last opened tab. So if B is opened after A, title gets its value from B. Try this: Detect Tab Id which called the script, fetch the url of that tab, which then becomes your title variable. As below:
chrome.pageAction.onClicked.addListener(function(tab) {
chrome.tabs.query({active:true},function(tabs){
//this function gets tabs details of the active tab, the tab that clicked the pageAction
var urltab = tabs[0].url;
//get the url of the tab that called this script - in your case, tab A or B.
chrome.tabs.create({url: urltab + title});
});
});