From 9632cd7087600b5ed0c6b038642a51190c54f26f Mon Sep 17 00:00:00 2001
From: Zoey Chen <zoeychen@google.com>
Date: Tue, 12 Oct 2021 03:59:55 +0000
Subject: [PATCH] [Settings] Add null protection to avoid the crash

Change-Id: Id933a33ecf2931445a57cf6588a9c9123c170707
Test: manual
Bug: 202162176
---
 .../network/telephony/NetworkProviderWifiCallingGroup.java    | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/com/android/settings/network/telephony/NetworkProviderWifiCallingGroup.java b/src/com/android/settings/network/telephony/NetworkProviderWifiCallingGroup.java
index bc116001ebd..14bdd4123ab 100644
--- a/src/com/android/settings/network/telephony/NetworkProviderWifiCallingGroup.java
+++ b/src/com/android/settings/network/telephony/NetworkProviderWifiCallingGroup.java
@@ -285,7 +285,9 @@ public class NetworkProviderWifiCallingGroup extends
         }
 
         public void unregister() {
-            mTelephonyManager.unregisterTelephonyCallback(this);
+            if (mTelephonyManager != null) {
+                mTelephonyManager.unregisterTelephonyCallback(this);
+            }
         }
     }