title: Disable button while ngForm is invalid
body: <p>I have an add modal in that I need the SAVE button to be disabled till the contents are filled. As the contents are filled the button should get enabled.Here is my code</p>
  
  <pre><code>&lt;div bsModal #editModal="bs-modal" class="modal fade" tabindex="-1" role="dialog" aria-labelledby="myLargeModalLabel" aria-hidden="true"&gt;
  &lt;div class="modal-dialog modal-md"&gt;
      &lt;div class="modal-content"&gt;
          &lt;form name='groupForm' #groupForm="ngForm" novalidate&gt;
              &lt;div class="modal-header"&gt;
                  &lt;h4 class="modal-title wd-title-popup"&gt;Add Access Group&lt;/h4&gt;
              &lt;/div&gt;
              &lt;div class="modal-body row"&gt;
                  &lt;div class="col-lg-12 col-md-12 col-sm-12 col-xs-12 accssContent paddingLeftClass"&gt;
                      &lt;md-input-container style='width: 100%;margin-bottom: 6px !important;'&gt;
                          &lt;input type="textbox" mdInput name="admin" [(ngModel)]="group.groupName" placeholder="Access Group Name" required&gt;
                      &lt;/md-input-container&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
              &lt;div md-theme="reports" class="modal-footer" style="text-align: center;"&gt;
                  &lt;div layout-align="end center" layout="row"&gt;
                      &lt;button md-raised-button class="md-raised color-white" (click)="editModal.hide()" style="width: 45%;margin: 10px 5px;background-color: #FF5252;"&gt;Cancel&lt;/button&gt;
                      &lt;button md-raised-button class="md-raised color-white" [disabled]="!groupForm.form.valid" (click)="accessGroup(group)" style="width: 45%;margin: 10px 5px;background-color:#58B6A2;"&gt;Save&lt;/button&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
          &lt;/form&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p></p>
  
  <p>This same is working fine with other buttons. Whats am I doing wrong here?</p>