title: In Magento2 (2.2.5) uicomponent form in frontend, SAVE button not appearing with form
body: <p>I added uiform in frontend. Form is loading but save button is not appearing. Code details:</p>
  
  <h1>1. employee_form.xml code:</h1>
  
  <pre><code>&lt;argument name="data" xsi:type="array"&gt;
      &lt;item name="js_config" xsi:type="array"&gt;
          &lt;item name="provider" xsi:type="string"&gt;employee_form.employee_form_data_source&lt;/item&gt;
      &lt;/item&gt;
      &lt;item name="label" xsi:type="string" translate="true"&gt;Assign Product Form&lt;/item&gt;
      &lt;item name="template" xsi:type="string"&gt;templates/form/collapsible&lt;/item&gt;
      &lt;item name="spinner" xsi:type="string"&gt;uiform_index_columns2&lt;/item&gt;
  &lt;/argument&gt;
  &lt;settings&gt;
      &lt;buttons&gt;
          &lt;button name="save" class="Cn\Uiform\Block\Employee\Form\SaveButton"/&gt;
          &lt;button name="back"&gt;
              &lt;url path="*/*/"/&gt;
              &lt;class&gt;back&lt;/class&gt;
              &lt;label translate="true"&gt;Back&lt;/label&gt;
          &lt;/button&gt;
      &lt;/buttons&gt;
      &lt;namespace&gt;employee_form&lt;/namespace&gt;
      &lt;dataScope&gt;data&lt;/dataScope&gt;
      &lt;deps&gt;
          &lt;dep&gt;employee_form.employee_form_data_source&lt;/dep&gt;
      &lt;/deps&gt;
  &lt;/settings&gt;
  &lt;dataSource name="employee_form_data_source"&gt;
      &lt;argument name="data" xsi:type="array"&gt;
          &lt;item name="js_config" xsi:type="array"&gt;
              &lt;item name="component" xsi:type="string"&gt;Magento_Ui/js/form/provider&lt;/item&gt;
          &lt;/item&gt;
      &lt;/argument&gt;
      &lt;settings&gt;
          &lt;submitUrl path="*/*/save"/&gt;
      &lt;/settings&gt;
      &lt;dataProvider class="Cn\Uiform\Model\DataProvider" name="employee_form_data_source"&gt;
          &lt;settings&gt;
              &lt;primaryFieldName&gt;id&lt;/primaryFieldName&gt;
              &lt;requestFieldName&gt;id&lt;/requestFieldName&gt;
          &lt;/settings&gt;
      &lt;/dataProvider&gt;
  &lt;/dataSource&gt;
  </code></pre>
  
  <h1>2. DataProvide.php methods code</h1>
  
  <pre><code>public function prepareMeta(array $meta) {
      return $meta;
  }
  public function getData() {
      return [];
  }
  </code></pre>
  
  <h1>3. SaveButton.php class code</h1>
  
  <p>use Magento\Framework\View\Element\UiComponent\Control\ButtonProviderInterface;</p>
  
  <pre><code>class SaveButton extends GenericButton implements ButtonProviderInterface {
  
      public function getButtonData() {
          return [
              'label' =&gt; __('Save Slide'),
              'class' =&gt; 'save primary',
              'data_attribute' =&gt; [
                  'mage-init' =&gt; ['button' =&gt; ['event' =&gt; 'save']],
                  'form-role' =&gt; 'save',
              ],
              'sort_order' =&gt; 90,
          ];
      }
  }
  </code></pre>
  
  <h1>4. di.xml</h1>
  
  <pre><code>&lt;!--for edit uiform--&gt;
  &lt;type name="Magento\Framework\View\Element\UiComponent\DataProvider\CollectionFactory"&gt;
      &lt;arguments&gt;
          &lt;argument name="collections" xsi:type="array"&gt;
              &lt;item name="employee_form_data_source" xsi:type="string"&gt;Cn\Uiform\Model\ResourceModel\Employee\Collection&lt;/item&gt;
          &lt;/argument&gt;
      &lt;/arguments&gt;
  &lt;/type&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/mlhPE.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mlhPE.png" alt="enter image description here"></a></p>
  
  <p>=> But, the ui form is loading without <strong>SAVE</strong> button.</p>