nwjs/nw.js · error · TypeError

Invalid option.

Error message

Invalid option.

What it means

Thrown by the Tray constructor when the option argument is not an object (typeof option != 'object'). The constructor requires an options object carrying at least a 'title' or 'icon' field. Note typeof null === 'object' so null bypasses this check and fails later at the hasOwnProperty calls.

Source

Thrown at src/resources/api_nw_tray.js:26

trayEvents.clickEvent = bindingUtil.createCustomEvent("NWObjectTrayClick", false, false);
trayEvents.clickEvent.addListener(function(id) {
  var tray = trayEvents.objs[id];
  if (!tray)
    return;
  var args = Array.prototype.slice.call(arguments, 1);
  args.unshift('click');
  tray.emit.apply(tray, args);
});

function Tray(option) {
  if (!(this instanceof Tray)) {
    return new Tray(option);
  }
  EventEmitter.apply(this);

  if (typeof option != 'object')
    throw new TypeError('Invalid option.');

  if (!option.hasOwnProperty('title') && !option.hasOwnProperty('icon'))
    throw new TypeError("Must set 'title' or 'icon' field in option");

  if (!option.hasOwnProperty('title'))
    option.title = '';
  else
    option.title = String(option.title);

  if (option.hasOwnProperty('icon')) {
    option.shadowIcon = String(option.icon);
    option.icon = nwNative.getAbsolutePath(option.icon);
  }

  if (option.hasOwnProperty('alticon')) {
    option.shadowAlticon = String(option.alticon);
    option.alticon = nwNative.getAbsolutePath(option.alticon);
  }

View on GitHub (pinned to e15da848e9)

Solutions

1. Pass an options object: new nw.Tray({ title: 'My App' }) or new nw.Tray({ icon: 'icon.png' }).
2. Ensure the argument is defined and an object literal before construction.

Example fix

// before
new nw.Tray('My App');
// after
new nw.Tray({ title: 'My App' });

if (typeof option !== 'object' || option === null) {
  throw new TypeError('Tray option must be a non-null object');
}

function isTrayOption(o) { return typeof o === 'object' && o !== null && !Array.isArray(o); }

When it happens

Trigger: new nw.Tray('My App') (string); new nw.Tray() (undefined); new nw.Tray(123) (number); passing a pre-ES5 primitive wrapper.

Common situations: Assuming the constructor takes a title string directly; migrating from an API with a simpler signature; passing a variable that was conditionally assigned.

Related errors

• Invalid menu type: {option.type}
• Invalid option.
• Invalid MenuItem type: {option.type}
• A normal MenuItem must have a label
• Invalid option.

AI-assisted analysis of nwjs/nw.js@e15da848e9 (2026-08-13). Data as JSON: /api/errors/e72ca88f63a7d6dc. Report an issue: GitHub.