From d4c841a4598747cb874c2a17a584310540a3346f Mon Sep 17 00:00:00 2001
From: "zhijia,.zhang" <jiahut@gmail.com>
Date: Fri, 23 Jan 2015 15:02:37 +0800
Subject: [PATCH] fix the undefined object call func

---
 js/angular/service/history.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/js/angular/service/history.js b/js/angular/service/history.js
index e886146c29..2541825535 100644
--- a/js/angular/service/history.js
+++ b/js/angular/service/history.js
@@ -313,7 +313,8 @@ function($rootScope, $state, $location, $window, $timeout, $ionicViewSwitcher, $
               // the forward has a history
               for (x = tmp.stack.length - 1; x >= forwardView.index; x--) {
                 // starting from the end destroy all forwards in this history from this point
-                tmp.stack[x].destroy();
+                var stack_x = tmp.stack[x];
+                stack_x && stack_x.destroy && stack_x.destroy();
                 tmp.stack.splice(x);
               }
               historyId = forwardView.historyId;