title: How to validate forms in modal with tabs and angularJs
body: <p>I have a modal form with angular and uib-tabset.</p>
  
  <p>I have only a footer in modal.
  Each tabset  has a form( A B and C).</p>
  
  <p>When I try enabled/disable the save button on footer, I can´t acesss 
  acesss the forms. They are undefined.</p>
  
  <p>So, in the 'Save' button(see plunker) -  formA.$invalid doesn´t works. I think it is a scope problem.</p>
  
  <p>I´d prefer doesn´t put a global form to all tabs.</p>
  
  <p>Is there some workaround to solve it?</p>
  
  <p>Markup:</p>
  
  <pre><code>&lt;div class="modal-content"&gt;
      &lt;div class="modal-header bg-primary"&gt;
        &lt;button type="button" class="close" ng-click="doCancel()" aria-hidden="true"&gt;&amp;times;&lt;/button&gt;
        &lt;h4 class="modal-title" id="ativarSmsLabel"&gt;
          Test
        &lt;/h4&gt;
      &lt;/div&gt;
      &lt;div class="modal-body"&gt;
          &lt;uib-tabset active="activePill" vertical="false" type="pills"&gt;
            &lt;uib-tab index="0" heading="Agendamento"&gt;     
                              &lt;form name="formA" novalidate&gt;
                                  &lt;input type="text" ng-model="testA"
                               &lt;/form&gt;
                          &lt;/div&gt;
                      &lt;/div&gt;
                  &lt;/div&gt;
            &lt;/uib-tab&gt;
            &lt;uib-tab index="1" heading="Ficha"&gt;       
                &lt;form name="formB" novalidate&gt;
                                  &lt;input type="text" ng-model="testB"
                &lt;/form&gt;
            &lt;/uib-tab&gt;
            &lt;uib-tab index="2" heading="Histórico"&gt;
                  &lt;form name="formC" novalidate&gt;
                     &lt;input type="text" ng-model="testC"
                  &lt;/form&gt;
            &lt;/uib-tab&gt;
          &lt;/uib-tabset&gt;
      &lt;/div&gt;
  
       &lt;div class="modal-footer"&gt;
                 &lt;div class="btn-toolbar"&gt;
                     &lt;button type="button" class="btn btn-sm btn-primary pull-right" ng-click="saveItem()"
                      aria-hidden="true" ng-disabled="formA.$invalid"&gt;
                      Save
                    &lt;/button&gt;
                    &lt;button type="button" class="btn btn-sm pull-right" ng-click="doCancel()"
                      aria-hidden="true"&gt;
                      Close
                    &lt;/button&gt;
                 &lt;/div&gt;
        &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>