Question About Tabs

I defined a tab event ‘show.bs.tab’, but when i switch the tab, nothing was print. the code is as follows:


<?php

 echo \yii\bootstrap\Tabs::widget([

		     'items' => [

		         [

		             'label' => 'Artical',

		             'content' => 'aa',

		             'active' => true

		         ],

		         [

		             'label' => 'Mind',

		             'content' => \yii\base\View::render('_mind'),

		             'headerOptions' => []

		         ],

		         [

		             'label' => 'Dropdown',

					 'content' => 'drop'

		         ],

		     ],

 			'clientEvents' => [

 				'show.bs.tab' => 'function(e){console.log("ok");}'

 			]

		 ]);

?>