问Firefox添加-关于如何链接上下文菜单和面板小部件

EN

var panels = require("sdk/panel");
var self = require("sdk/self");

var panel = panels.Panel({
  contentURL: self.data.url("panel.html")
});

var cm = require("sdk/context-menu");
cm.Item({
  label: "Edit Image",
  context: cm.SelectorContext("img"),
  contentScript: 'self.on("click", function () {' +
                 '  self.postMessage(null);' +
                 '});',
  onMessage: function (msg) {
  panel.show({
    //position: button //set position to some anchor
  });
  }
});