<?= DatePicker::widget([
  'model' => $model,
  'attribute' => 'date',
  'template' => '{addon}{input}',
    'clientOptions' => [
      'autoclose' => true,
      'format' => 'dd-M-yyyy'
    ]
]);?>

<?= $form->field($model, 'date')->widget(
  DatePicker::className(), [
    // inline too, not bad
    'inline' => true,
    // modify template for custom rendering
    'template' => '<div class="well well-sm" style="background-color: #fff; width:250px">{input}</div>',
    'clientOptions' => [
      'autoclose' => true,
      'format' => 'dd-M-yyyy'
    ]
]);?>