From 1c78a95bf4353147b1a5cfe8101e7a6c08080eb3 Mon Sep 17 00:00:00 2001
From: Bentaimia Haddadi <bentaimia.haddadi@signify.com>
Date: Wed, 29 Dec 2021 16:44:37 +0100
Subject: [PATCH] Fix lookupCallback crash

---
 .../main/java/vn/hunghd/flutterdownloader/DownloadWorker.java | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/android/src/main/java/vn/hunghd/flutterdownloader/DownloadWorker.java b/android/src/main/java/vn/hunghd/flutterdownloader/DownloadWorker.java
index 8a3b4cda..b36e2459 100644
--- a/android/src/main/java/vn/hunghd/flutterdownloader/DownloadWorker.java
+++ b/android/src/main/java/vn/hunghd/flutterdownloader/DownloadWorker.java
@@ -126,6 +126,10 @@ private void startBackgroundIsolate(Context context) {
                 // lookup will fail.
                 FlutterCallbackInformation flutterCallback =
                         FlutterCallbackInformation.lookupCallbackInformation(callbackHandle);
+                if (flutterCallback == null) {
+                    log("Fatal: failed to find callback");
+                    return;
+                }
 
                 backgroundFlutterEngine = new FlutterEngine(context);