<!DOCTYPE html>
<html>

<head>
  <script data-require="angular.js@1.4.8" data-semver="1.4.8" src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.4.8/angular.min.js"></script>
</head>

<body ng-app>
  <div id="form_wrapper" ng-init="notSubmitted = true">
    <form ng-show="notSubmitted">
      <input type="text" name="feedback" />
      <input type="submit" value="Submit Feedback" ng-click="notSubmitted = !notSubmitted" />
    </form>
    <div ng-hide="notSubmitted">Thanks for submitting your feedback!</div>
  </div>
</body>

</html>
http://blog.allii.ir/2016/01/angularjs-begineer-intermediate-course-basics-part-one/#scopes