tinypin/chrome-extension/background.js

/**
 * Returns a handler which will open a new window when activated.
 */
function getClickHandler() {
    return function(info, tab) {

        if ( !info.srcUrl.startsWith('http') ){
          window.alert("Image source is not a URL.");
          return;
        }

        var w = 700;
        var h = 800;
        var left = (screen.width/2)-(w/2);
        var top = (screen.height/2)-(h/2); 

        var q = "i=" + encodeURIComponent(info.srcUrl) + "&s=" + encodeURIComponent(tab.url);

        // The srcUrl property is only available for image elements.
        var url = 'http://localhost:3000/addpin.html#' + q;
    
        // Create a new window to the info page.
        // chrome.windows.create({ url: url, width: 520, height: 660 });
        chrome.windows.create({ url: url, width: w, height: h, left: left, top: top, type: 'popup' });
    };
  };
  
  /**
   * Create a context menu which will only show up for images.
   */
  chrome.contextMenus.create({
    "title" : "add to tinypin",
    "type" : "normal",
    "contexts" : ["image"],
    "onclick" : getClickHandler()
  });