coupon amount

@@ -577,6 +577,7 @@ coupon = {
         });
     },
     changeTicketsUse: function() {
+        var that = this;
         var coupons = [],
             price = 0;
 
@@ -591,12 +592,15 @@ coupon = {
 
         if (coupons.length) {
             this.$ticketUseTip.find('.num').text(coupons.length);
-            this.$ticketUseTip.find('.price').text('- ¥' + price.toFixed(2));
-            this.$ticketUseTip.removeClass('hide');
             order.couponCode = coupons.join(',');
 
             // 重新计算订单价格
-            compute();
+            compute(0, function(data) {
+                if (data.code === 200) {
+                    that.$ticketUseTip.find('.price').text('- ¥' + data.data.coupon_amount.toFixed(2));
+                    that.$ticketUseTip.removeClass('hide');
+                }
+            });
         }
     },
     cancelTicketUse: function() {