title: Showing blank rows for filters in Yii2.0 with GridView
body: <p>I have set up GridView to crfeate my table in Yii2.0 as follows:</p>
  
  <pre><code>&lt;?= \yii\grid\GridView::widget([
      'dataProvider' =&gt; $model-&gt;dataProvider,
      'filterModel' =&gt; $model-&gt;searchModel,
      'columns' =&gt; [
          [
              'label' =&gt; Yii::t( $cat, 'Id' ),
              'value' =&gt; 'id',
          ],
          [
              'label' =&gt; Yii::t( $cat, 'Title' ),
              'format' =&gt; 'raw',
              'value' =&gt; function ( $data ) {
                  if ( $data['status_code'] != 5 )
                  {
                      return Html::a( $data['title'], '/signer/view/' . $data['id'] );
                  }
                  else
                  {
                      return $data['title'];
                  }
              },
          ],
          [
              'label' =&gt; Yii::t( $cat, 'Description' ),
              'value' =&gt; 'description',
          ],
          [
              'label' =&gt; Yii::t( $cat, 'Filename' ),
              'value' =&gt; 'filename',
          ],
          [
              'label' =&gt; Yii::t( $cat, 'Status' ),
              'value' =&gt; 'status',
              'contentOptions' =&gt; function ( $data ) {
                      $statuses = [
                          1 =&gt; 'text-primary',    # New
                          2 =&gt; 'text-warning',    # Unsigned
                          3 =&gt; 'text-warning',    # Partially signed
                          4 =&gt; 'text-success',    # Signed
                          5 =&gt; 'text-danger',     # Deleted
                      ];
                      return [ 'class' =&gt; $statuses[$data['status_code']] ];
                  }
          ],
          [
              'label' =&gt; Yii::t( $cat, 'Created' ),
              'value' =&gt; 'created',
          ],
          //[ 'class' =&gt; 'yii\grid\ActionColumn' ],
      ],
  ]);
  ?&gt;
  </code></pre>
  
  <p>I get all the correct data, but instead of filter inputs, I get empty rows.</p>
  
  <p><img src="https://i.stack.imgur.com/VkGQ9.png" alt="enter image description here"></p>
  
  <p><strong>Why is that? What am I missing?</strong></p>
  
  <p>PS: The search model itself works fine, meaning, when I add to the url <code>?title=asd</code> it actually get the search results!</p>