From 16b955bd1f6b321cbe88cc628c5e8bdd1ba57cc2 Mon Sep 17 00:00:00 2001
From: Andrew Jack <me@andrewjack.uk>
Date: Wed, 9 May 2018 13:04:40 -0700
Subject: [PATCH] Fix Android modal crash:
 android.view.WindowManager$BadTokenException

Summary:
<!--
  Required: Write your motivation here.
  If this PR fixes an issue, type "Fixes #issueNumber" to automatically close the issue when the PR is merged.
-->

Fixes a crash with the Android Dialog. This occurs when the Activity is finishing or has been removed and React Native requests the modal to be shown.

Stacktrace here:
```
Caused by android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@f125ea3 is not valid; is your activity running?
       at android.view.ViewRootImpl.setView(ViewRootImpl.java:683)
       at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:319)
       at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:85)
       at android.app.Dialog.show(Dialog.java:326)
       at com.facebook.react.views.modal.ReactModalHostView.showOrUpdate(ReactModalHostView.java:256)
       at com.facebook.react.views.modal.ReactModalHostManager.onAfterUpdateTransaction(ReactModalHostManager.java:107)
       at com.facebook.react.views.modal.ReactModalHostManager.onAfterUpdateTransaction(ReactModalHostManager.java:28)
       at com.facebook.react.uimanager.ViewManager.updateProperties(ViewManager.java:35)
       at com.facebook.react.uimanager.NativeViewHierarchyManager.createView(NativeViewHierarchyManager.java:233)
       at com.facebook.react.uimanager.UIViewOperationQueue$CreateViewOperation.execute(UIViewOperationQueue.java:153)
       at com.facebook.react.uimanager.UIViewOperationQueue$1.run(UIViewOperationQueue.java:816)
       at com.facebook.react.uimanager.UIViewOperationQueue.flushPendingBatches(UIViewOperationQueue.java:929)
       at com.facebook.react.uimanager.UIViewOperationQueue.access$2100(UIViewOperationQueue.java:47)
       at com.facebook.react.uimanager.UIViewOperationQueue$2.runGuarded(UIViewOperationQueue.java:887)
       at com.facebook.react.bridge.GuardedRunnable.run(GuardedRunnable.java:21)
       at android.os.Handler.handleCallback(Handler.java:815)
       at android.os.Handler.dispatchMessage(Handler.java:104)
       at android.os.Looper.loop(Looper.java:207)
       at android.app.ActivityThread.main(ActivityThread.java:5728)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:679)
```

Related issues: #18570 & #18634

mdvacca added to this file in https://github.com/facebook/react-native/commit/e5c2a66897b9c562c549e63adcf70783ea34c418
Doesn't look like the issue was introduced in the above change, but it masks the issue. The wrapping if block should not allow a null activity to display a dialog.

<!--
  Required: Write your test plan here. If you changed any code, please provide us with
  clear instructions on how you verified your changes work. Bonus points for screenshots and videos!
-->

Run sample app on Android and display dialog when app is about to close.

<!--
  Required.
  Help reviewers and the release process by writing your own release notes. See below for an example.
-->

[ANDROID] [BUGFIX] [Modal] - Fix Android BadTokenException crash

<!--
  **INTERNAL and MINOR tagged notes will not be included in the next version's final release notes.**

    CATEGORY
  [----------]      TYPE
  [ CLI      ] [-------------]    LOCATION
  [ DOCS     ] [ BREAKING    ] [-------------]
  [ GENERAL  ] [ BUGFIX      ] [ {Component} ]
  [ INTERNAL ] [ ENHANCEMENT ] [ {Filename}  ]
  [ IOS      ] [ FEATURE     ] [ {Directory} ]   |-----------|
  [ ANDROID  ] [ MINOR       ] [ {Framework} ] - | {Message} |
  [----------] [-------------] [-------------]   |-----------|

 EXAMPLES:

 [IOS] [BREAKING] [FlatList] - Change a thing that breaks other things
 [ANDROID] [BUGFIX] [TextInput] - Did a thing to TextInput
 [CLI] [FEATURE] [local-cli/info/info.js] - CLI easier to do things with
 [DOCS] [BUGFIX] [GettingStarted.md] - Accidentally a thing/word
 [GENERAL] [ENHANCEMENT] [Yoga] - Added new yoga thing/position
 [INTERNAL] [FEATURE] [./scripts] - Added thing to script that nobody will see
-->
Closes https://github.com/facebook/react-native/pull/18996

Differential Revision: D7938147

Pulled By: hramos

fbshipit-source-id: f4ffd1746304d6184d727339072a7e926ffdaf39
---
 .../java/com/facebook/react/views/modal/ReactModalHostView.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/views/modal/ReactModalHostView.java b/ReactAndroid/src/main/java/com/facebook/react/views/modal/ReactModalHostView.java
index 00eac510a..ab0491fe4 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/views/modal/ReactModalHostView.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/views/modal/ReactModalHostView.java
@@ -250,7 +250,7 @@ public class ReactModalHostView extends ViewGroup implements LifecycleEventListe
     if (mHardwareAccelerated) {
       mDialog.getWindow().addFlags(WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED);
     }
-    if (currentActivity == null || !currentActivity.isFinishing()) {
+    if (currentActivity != null && !currentActivity.isFinishing()) {
       mDialog.show();
     }
   }