title: AngularJS validation issue
body: <p>I try to validate a form <code>productForm</code> by using AngularJS directives, so I try:</p>
  
  <pre><code>&lt;form id="productForm" name="productForm" novalidate&gt;
       &lt;div style="width: 100%; margin-top: 15px; float: right; "&gt;
                  &lt;label style="width:103px;float:right" class="col-sm-2" for="ProductName"&gt;ProductName: &lt;/label&gt;
  
                  &lt;div style="float:right" class="col-sm-5"&gt;
                      &lt;input ng-required="true" class="form-control" style="float:right" type="text" id="ProductName" name="ProductName" ng-model="modal.ProductName" value="" /&gt;
                  &lt;/div&gt;
                  &lt;div style="float:right" class="col-md-7" &gt;
                      &lt;span class="help-block" ng-if="productForm.ProductName.$error.required &amp;&amp; productForm.ProductName.$dirty &amp;&amp; productForm.ProductName.$touched "&gt; Name is Must&lt;/span&gt;
                  &lt;/div&gt;
  
      &lt;/div&gt;
      &lt;button class="btn" style="background-color: #ed9c28;" type="button" ng-click="Save()" ng-disabled="productForm.$invalid"&gt;Save&lt;/button&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>In this way the problem is: when user touch the <code>ProductName</code> and then it lost focus, the required message didn't show( it just was shown when user type in the input and then clear whole text from the input, but I want to show error message when the input is empty), i try to use <code>productForm.ProductName.$touched</code> in <code>ng-if</code> of error message for do it, but it doesn't work, How can I do it?</p>