Edit in JSFiddle

require(['knockout',
  'ojs/ojcore',
  'ojs/ojknockout',
  'ojs/ojoffcanvas',
  'ojs/ojselectcombobox'
], function(ko, oj, $) {
  'use strict';

  var ViewModel = function() {
    var self = this;

    //offcanvas options
    var toastOptions = {
      "displayMode": "overlay",
      "selector": "#toast"
    };
    
    self.browser = ko.observable(['CH']);
    
    var closeToast = function() {
      return oj.OffcanvasUtils.close(toastOptions);
    };

    self.browserChangedHandler = function (event, data) {
      if (data.option == "value") {
        oj.OffcanvasUtils.open(toastOptions);
        window.setTimeout(closeToast, 5*1000);
      }
    };

  };


  ko.applyBindings(new ViewModel());
});


//RequireJS configs (usually these come first in main.js, but they don't have to)
requirejs.config({
  // Path mappings for the logical module names
  paths: {
    'knockout': '//cdnjs.cloudflare.com/ajax/libs/knockout/3.4.0/knockout-min',
    'jquery': '//cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min',
    "jqueryui": "//cdnjs.cloudflare.com/ajax/libs/jqueryui/1.11.4/jquery-ui",
    "jqueryui-amd": "//rawgit.com/jquery/jquery-ui/1-11-stable/ui",

    "promise": "//cdn.lukej.me/es6-promise/1.0.0/promise.min",
    "hammerjs": "//cdnjs.cloudflare.com/ajax/libs/hammer.js/2.0.4/hammer.min",
    "ojdnd": "//rawgit.com/oracle/oraclejet/2.0.1/dist/js/libs/dnd-polyfill/dnd-polyfill-1.0.0.min",
    "ojs": "//rawgit.com/oracle/oraclejet/2.0.1/dist/js/libs/oj/debug",
    "ojL10n": "//rawgit.com/oracle/oraclejet/2.0.1/dist/js/libs/oj/ojL10n",
    "ojtranslations": "//rawgit.com/oracle/oraclejet/2.0.1/dist/js/libs/oj/resources",
    "text": "//cdnjs.cloudflare.com/ajax/libs/require-text/2.0.12/text.min",
    "signals": "//cdnjs.cloudflare.com/ajax/libs/js-signals/1.0.0/js-signals.min",

  },
  // Shim configurations for modules that do not expose AMD
  shim: {
    'jqueryui-amd': {
      exports: "$",
      deps: ['jquery']
    },
    'jquery': {
      exports: ['jQuery', '$']
    }
  },
  config: {
    ojL10n: {
      merge: {
        //'ojtranslations/nls/ojtranslations': 'resources/nls/menu'
        // The following addes en-US to the r.js bundle
        //'ojtranslations/nls/ojtranslations': '../../oj/resources/nls/en-US/localeElements'
      }
    }
  }
});

<div class="oj-offcanvas-outer-wrapper">
  <div id="wrapper" class="oj-offcanvas-inner-wrapper">

    <!-- toast offcanvas -->
    <div id="toast" class="oj-offcanvas-top oj-panel oj-panel-alt2">
      <div>Confirmation: You chose browser <strong data-bind="text: browser"></strong>.
      </div>
    </div>


    <!-- this content will be overlayed by the toast notification -->
    <div class="oj-panel oj-margin">
      <label for="basicSelect">Select a browser</label>
      <select id="basicSelect"
        data-bind="ojComponent: {component: 'ojSelect',
                                 value: browser,
                                 optionChange: browserChangedHandler,
                                 rootAttributes: {style:'max-width:20em'}}">
        <option value="IE">Internet Explorer</option>
        <option value="FF">Firefox</option>
        <option value="CH">Chrome</option>
        <option value="OP">Opera</option>
        <option value="SA">Safari</option>
      </select>
    </div>
  </div> <!-- /end inner-wrapper -->

</div><!-- /end outer-wrapper -->

@import url('//rawgit.com/oracle/oraclejet/2.0.1/dist/css/alta/oj-alta-min.css');

#toast {
  /* Make the message look pretty */
  border: 1px solid #0572ce;
  box-shadow: 0 1px 3px #777;
 
  /* set the location of the toast message */
  left: auto;
  right: 10px;
  width: 200px;

  /* z-index required to overlay oj form controls */
  z-index: 1;
}