wordpress woocommerce side cart

I want to do something special about woocomerce and adding product to cart. When the customer adds a product to his basket, I have a sidebar that opens automatically with the basket, but it closes and the product is added after. I would like it to be added when the sidebar is open.

How to do ?

Thank you !

    jQuery('.single_add_to_cart_button').click(function(){

    var action = jQuery('#taille').val();

    if( action === ""){
        jQuery('.variations .value').append('<span id="info-option">Veuillez sélectionner une taille</span>');
    }

    else{
        jQuery('#info-option').css('display','none');
        jQuery('body').addClass('oc-sidebar-opned');
    }

    jQuery('.oc-close').click(function(){
        jQuery('body').removeClass('oc-sidebar-opned');         
    });
});