title: set default value in select2 dropdown in yii2
body: <p>I have a kartik select2 dependent dropdown in yii2 and i want to select a value as a default selected value.</p>
  
  <pre><code>&lt;?=$form-&gt;field($EmployeeLeaveModel, 'EmployeeID')-&gt;widget(Select2::classname(), [
                          'data' =&gt; $Employee,
                          'language' =&gt; 'en',
                          'options' =&gt; ['placeholder' =&gt; 'Select Employee  ...'],
                          'pluginOptions' =&gt; [
                                  'allowClear' =&gt; true
                               ],
                  ]);
          ?&gt;
  </code></pre>
  
  <p>How do i get a default value as selected in the dropdown?</p>