Chrome Extension open popup relative to current window

Question

I'm trying to create a Chrome extension that will pop up a new window in a position relative to the recently focused window. I don't think I'm using the chrome.windows.getCurrent or chrome.windows.getLastFocused methods properly to do this. Every time I do, I get an undefined alert when I try to show a property of that window.

In my background.js file, I have:

chrome.pageAction.onClicked.addListener(showPopup);
function showPopup() {
  var left = chrome.windows.getCurrent(function (w) {
    w.left - 200; 
    // also tried: return w.left - 200;
  });
  alert(left); // undefined
}

Reading the chrome.windows API docs left me confused on how to actually return an attribute of a window. Can anyone shed some light here?

Answer 1

I'm not sure if there's another (or better) way to do this, but I got this to work:

chrome.pageAction.onClicked.addListener(getCurrentInfo);
function getCurrentInfo() {
  chrome.windows.getCurrent(showPopup);
}
function showPopup(win) {
  alert(win.left); // correct pixel count from left
}

My original attempt was wrong because I was trying to return a value from the get() callback function and place that into a variable. This, essentially evaluated to var left = chrome.windows.get(winId, 790) , which is an invalid function call. Rather than that, my call to chrome.windows.create() needed to be inside the callback function.

Also, a miss before was that the click listener calls a function with a tab parameter, not a window parameter. So I needed the getCurrentInfo() function to pass in a tab and then chrome.windows.getCurrent() to pass in window info.