sample.js

// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
var elty;
var elt;
// A generic onclick callback function.
function genericOnClick(info, tab) {
	chrome.extension.getBackgroundPage().console.log('foo');
	var newURL = "https://www.google.com/searchbyimage?&image_url="+elty;
	chrome.tabs.create({ url: newURL });
	elty = null;
}

chrome.extension.onMessage.addListener(function(request, sender, sendResponse) {
	//console.log("gotmessage");
    if(request.greeting == "getClickedBi") {
		elty = request.value;
        sendResponse("got it");
    }
});

// Create one test item for each context type.
/*var contexts = ["page","selection","link","editable","image","video",
                "audio"];*/
/*for (var i = 0; i < contexts.length; i++) {
  var context = contexts[i];
  var title = "Test '" + context + "' menu item";
  var id = chrome.contextMenus.create({"title": title, "contexts":[context],
                                       "onclick": genericOnClick});
  console.log("'" + context + "' item:" + id);
}*/

function mycallback(info, tab) {
    chrome.tabs.sendRequest(tab.id, "getClickedBi", function(bi) {
        elt.value = bi.value;
		elty.value = bi.value;
		console.log("lolol");
		console.log(elty.value);
    });
}

// Create a parent item and two children.
var parent = chrome.contextMenus.create({"title": "Search Google for this background image", "onclick": genericOnClick});
/*var child1 = chrome.contextMenus.create(
  {"title": "Child 1", "parentId": parent, "onclick": genericOnClick});
var child2 = chrome.contextMenus.create(
  {"title": "Child 2", "parentId": parent, "onclick": genericOnClick});
console.log("parent:" + parent + " child1:" + child1 + " child2:" + child2);
*/

// Create some radio items.
/*function radioOnClick(info, tab) {
  console.log("radio item " + info.menuItemId +
              " was clicked (previous checked state was "  +
              info.wasChecked + ")");
}*/
/*var radio1 = chrome.contextMenus.create({"title": "Radio 1", "type": "radio",
                                         "onclick":radioOnClick});
var radio2 = chrome.contextMenus.create({"title": "Radio 2", "type": "radio",
                                         "onclick":radioOnClick});
console.log("radio1:" + radio1 + " radio2:" + radio2);

*/
// Create some checkbox items.
/*function checkboxOnClick(info, tab) {
  console.log(JSON.stringify(info));
  console.log("checkbox item " + info.menuItemId +
              " was clicked, state is now: " + info.checked +
              "(previous state was " + info.wasChecked + ")");

}*/
/*var checkbox1 = chrome.contextMenus.create(
  {"title": "Checkbox1", "type": "checkbox", "onclick":checkboxOnClick});
var checkbox2 = chrome.contextMenus.create(
  {"title": "Checkbox2", "type": "checkbox", "onclick":checkboxOnClick});
console.log("checkbox1:" + checkbox1 + " checkbox2:" + checkbox2);
*/

// Intentionally create an invalid item, to show off error checking in the
// create callback.
/*console.log("About to try creating an invalid item - an error about " +
            "item 999 should show up");
chrome.contextMenus.create({"title": "Oops", "parentId":999}, function() {
  if (chrome.extension.lastError) {
    console.log("Got expected error: " + chrome.extension.lastError.message);
  }
});
*/