Method watch

docs/app/js/sanddance-app.js:92366–92368

(event, handler, opts)

        this._addEventHandler(event, handler, opts, true);
    }
    watch(event, handler, opts) {
        this._addEventHandler(event, handler, opts, false, true);
    }
    off(event, handler) {
        this._removeEventHandler(event, handler);
    }