title: ng-show doesn't work when the boolean flag is reset in controller
body: <p>I have an input form where I am submitting details using <code>$http</code> in controller to server. On successful return, I want to give user alert that data is saved. But it is just not working and I am clueless after trying hard for many hours. </p>
  
  <p>Here is the HTML code :</p>
  
  <p>UI Code: </p>
  
  <pre><code>&lt;div class="alert alert-success span-5 offset3" ng-show="message"&gt;
      &lt;button type="button" class="close" data-dismiss="alert"&gt;&amp;times;&lt;/button&gt;
      &lt;strong&gt;Success!&lt;/strong&gt; The review has been successfully created.
  &lt;/div&gt;
  </code></pre>
  
  <p>And here is the controller logic, where I am flipping the flag.</p>
  
  <pre><code>$http.post('reviews/create',jsonData)
  .success(function (data) {
      $scope.message=true
  })
  </code></pre>
  
  <p>The response comes in the success block, which I have tested but then when I change flag 'message' status, the alert is not shown on UI screen. ng-show is not picking changes from $scope.message done in controller. Please suggest a solution. I tried making message as ng-model too using hidden field so that it's there in scope.
  My view is visible in controller as i pulled out data and submitted successfully to the     server.</p>