simpleCart(js)

Documentation » update

'update' Event

The ‘update’ event is triggered after the cart has been updated saved.  You can use this to know when changes have been made to the cart.

simpleCart.bind( 'update' , function(){
  console.log( "Whoa, the cart total is now at " + simpleCart.toCurrency( simpleCart.grandTotal() ) + "! Nice!" ); 
});