From 7ac6fa7a10ce5f0d1e67369650d0b2034e108145 Mon Sep 17 00:00:00 2001
From: Andrew Jack <me@andrewjack.uk>
Date: Fri, 28 Jul 2017 07:33:53 -0700
Subject: [PATCH] Check if fresco is initialised before clearing memory caches

Summary:
Fixes the following crash:
```
Fatal Exception: java.lang.RuntimeException: Unable to destroy activity {com.example/com.example.MainActivity}: java.lang.NullPointerException: ImagePipelineFactory was not initialized!
       at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3831)
       at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3849)
       at android.app.ActivityThread.access$1500(ActivityThread.java:150)
       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1398)
       at android.os.Handler.dispatchMessage(Handler.java:102)
       at android.os.Looper.loop(Looper.java:148)
       at android.app.ActivityThread.main(ActivityThread.java:5417)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:764)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
Caused by java.lang.NullPointerException: ImagePipelineFactory was not initialized!
       at com.facebook.common.internal.Preconditions.checkNotNull(Preconditions.java:226)
       at com.facebook.imagepipeline.core.ImagePipelineFactory.getInstance(ImagePipelineFactory.java:74)
       at com.facebook.drawee.backends.pipeline.Fresco.getImagePipelineFactory(Fresco.java:92)
       at com.facebook.drawee.backends.pipeline.Fresco.getImagePipeline(Fresco.java:97)
       at com.facebook.react.modules.fresco.FrescoModule.onHostDestroy(FrescoModule.java:186)
       at com.facebook.react.bridge.ReactContext.onHostDestroy(ReactContext.java:240)
       at com.facebook.react.ReactInstanceManager.moveToBeforeCreateLifecycleState(ReactInstanceManager.java:667)
       at com.facebook.react.ReactInstanceManager.onHostDestroy(ReactInstanceManager.java:586)
       at com.facebook.react.ReactInstanceManager.onHostDestroy(ReactInstanceManager.java:599)
       at com.facebook.react.ReactActivityDelegate.onDestroy(ReactActivityDelegate.java:142)
       at com.facebook.react.ReactActivity.onDestroy(ReactActivity.java:72)
       at android.app.Activity.performDestroy(Activity.java:6456)
       at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1143)
       at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3818)
       at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3849)
       at android.app.ActivityThread.access$1500(ActivityThread.java:150)
       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1398)
       at android.os.Handler.dispatchMessage(Handler.java:102)
       at android.os.Looper.loop(Looper.java:148)
       at android.app.ActivityThread.main(ActivityThread.java:5417)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:764)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
```

This was introduced by https://github.com/facebook/react-native/commit/d9ae27ba89c0beda0c76d3a227c2a453948db1a2

1. Create app with an image to be loaded
2. Background app before fresco has been initialised. (Very tight window to do this)
3. Should not crash

cc foghina
Closes https://github.com/facebook/react-native/pull/14359

Differential Revision: D5508505

Pulled By: hramos

fbshipit-source-id: 5a66d594625783f1c30180fe78c5baddb4f835aa
---
 .../java/com/facebook/react/modules/fresco/FrescoModule.java    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/modules/fresco/FrescoModule.java b/ReactAndroid/src/main/java/com/facebook/react/modules/fresco/FrescoModule.java
index e1e227e595b8cb..936a48a5ef6608 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/modules/fresco/FrescoModule.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/modules/fresco/FrescoModule.java
@@ -182,7 +182,7 @@ public void onHostDestroy() {
     // According to the javadoc for LifecycleEventListener#onHostDestroy, this is only called when
     // the 'last' ReactActivity is being destroyed, which effectively means the app is being
     // backgrounded.
-    if (mClearOnDestroy) {
+    if (hasBeenInitialized() && mClearOnDestroy) {
       Fresco.getImagePipeline().clearMemoryCaches();
     }
   }