From 54b6df669b050b5ad5503f370f50a44a9af501af Mon Sep 17 00:00:00 2001
From: Manol Donev <manoldonev@users.noreply.github.com>
Date: Mon, 17 Dec 2018 15:27:52 +0200
Subject: [PATCH] fix(android): animator restore logic on simulated nav (#6710)

---
 tns-core-modules/ui/frame/frame.android.ts | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/tns-core-modules/ui/frame/frame.android.ts b/tns-core-modules/ui/frame/frame.android.ts
index 1f56a8eb2c..0322aaf3c6 100644
--- a/tns-core-modules/ui/frame/frame.android.ts
+++ b/tns-core-modules/ui/frame/frame.android.ts
@@ -527,10 +527,22 @@ function getAnimatorState(entry: BackstackEntry): AnimatorState {
 
 function restoreAnimatorState(entry: BackstackEntry, snapshot: AnimatorState): void {
     const expandedEntry = <any>entry;
-    expandedEntry.enterAnimator = snapshot.enterAnimator;
-    expandedEntry.exitAnimator = snapshot.exitAnimator;
-    expandedEntry.popEnterAnimator = snapshot.popEnterAnimator;
-    expandedEntry.popExitAnimator = snapshot.popExitAnimator;
+    if (snapshot.enterAnimator) {
+        expandedEntry.enterAnimator = snapshot.enterAnimator;
+    }
+    
+    if (snapshot.exitAnimator) {
+        expandedEntry.exitAnimator = snapshot.exitAnimator;
+    }
+
+    if (snapshot.popEnterAnimator) {
+        expandedEntry.popEnterAnimator = snapshot.popEnterAnimator;
+    }
+    
+    if (snapshot.popExitAnimator) {
+        expandedEntry.popExitAnimator = snapshot.popExitAnimator;
+    }
+
     expandedEntry.transitionName = snapshot.transitionName;
 }