Cant'enable extension

[ashik1729]

i just try to enable extesion fron spinner . but it can't work for me

<?php

                echo ListView::widget([
                    'dataProvider' => $dataProvider,
                    'itemOptions' => ['class' => 'item'],
                    'itemView' => '_item',
                    'pager' => ['class' => \kop\y2sp\ScrollPager::className(),
                        'spinnerTemplate' => '<div class="ias-spinner" style="text-align: center;"><img src="{src}"/></div>',
                        'triggerText' => 'Load More Data',
                        'noneLeftText' => 'No more result to display',
                        'eventOnScroll' => true,
                        'triggerOffset' => 6,
                        'eventOnRendered' => 'function() {loadPost();}',
                        // 'triggerTemplate' => '{text}',
                        'enabledExtensions' => [
                            'EXTENSION_TRIGGER'=> true,
                              'EXTENSION_HISTORY' => false,
                            'EXTENSION_PAGING'=>true,
                            'EXTENSION_SPINNER'=>true,

                            ],
                    ],

                ]);
                ?>

i get the error