const { ToggleButton } = require('sdk/ui/button/toggle');
const { Panel } = require("sdk/panel");

let button = ToggleButton({
  id: "my-button",
  label: "my button",
  icon: "./icon.png",
  onChange({checked}) {
    if (checked) panel.show({position: this});
  }
});

let panel = Panel({
  // `./` is a shortcut for add-on's "data" folder
  // so there is no need to use `self` module
  contentURL: './content.html',
  onHide() {
    button.state('window', {checked: false});
  }
});

panel.port.on("button-clicked", (message) => {
  console.log(message);
  panel.port.emit("clicked-received", "Got " + message);
});