slickjs-no-loop.js

var pauseState = true;
// On before slide change
slider.on('afterChange', function(event, slick, currentSlide, nextSlide){
    //check the length of total items in .gallery container
    //if that number is the same with the number of the last slider
    //Then pause the slider
    if( item_length === slider.slick('slickCurrentSlide') ){
        $('#pause-btn').toggle();
        $('#play-btn').toggle();
        $('.gallery').slick('slickPause');
        $(pauseState = true);
    };
});