From bb1fd4cb8a65f0c5d3319f7a715490dce8b3e1e1 Mon Sep 17 00:00:00 2001
From: Serge Lebedev <angly.cat@gmail.com>
Date: Sun, 6 May 2018 23:04:57 +0600
Subject: [PATCH] Fix setting undefined value to isTransitioning (#4124)

---
 packages/react-navigation/src/routers/StackRouter.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/react-navigation/src/routers/StackRouter.js b/packages/react-navigation/src/routers/StackRouter.js
index 779f1c76..ba314044 100644
--- a/packages/react-navigation/src/routers/StackRouter.js
+++ b/packages/react-navigation/src/routers/StackRouter.js
@@ -327,7 +327,7 @@ export default (routeConfigs, stackConfig = {}) => {
             isTransitioning:
               state.index !== lastRouteIndex
                 ? action.immediate !== true
-                : undefined,
+                : state.isTransitioning,
             index: lastRouteIndex,
             routes,
           };