修改绑定功能
diff --git a/www/js/billdetail.js b/www/js/billdetail.js
index 057b106..3615234 100644
--- a/www/js/billdetail.js
+++ b/www/js/billdetail.js
@@ -8,6 +8,9 @@
     onDeviceReady: function() {
         this.loadBill()
     },
+    toBack: function (){
+        window.history.back();
+    },
     loadBill: function() {
         var refno = window.localStorage.getItem("currentrefno");
         if (isEmpty(refno)) {