DevExtreme jQuery/JS - Handle Events

var viewModel = {
    menuInstance: {},
    menuOptions: {
        // ...
        onItemClick: function (info) {
            // Handles the "itemClick" event
        },
        onInitialized: function (info) {
            // Saves the widget instance
            viewModel.menuInstance = info.component;    
            // Handles the "initialized" event
        }
    }
};

ko.applyBindings(viewModel);