Register system callbacks on background thread

CHANGELOG.md

@@ -5,6 +5,9 @@
 * Avoid unnecessary BroadcastReceiver registration for monitoring device orientation
   [#1303](https://github.com/bugsnag/bugsnag-android/pull/1303)
 
+* Register system callbacks on background thread
+  [#1292](https://github.com/bugsnag/bugsnag-android/pull/1292)
+
 ## 5.9.5 (2021-06-25)
 
 * Unity: Properly handle ANRs after multiple calls to autoNotify and autoDetectAnrs

bugsnag-android-core/src/androidTest/java/com/bugsnag/android/MemoryTrimTest.java

@@ -36,6 +36,9 @@ public void onLowMemoryEvent() {
         when(context.getApplicationContext()).thenReturn(context);
         Client client = new Client(context, BugsnagTestUtils.generateConfiguration());
 
+        // block until observer is registered
+        client.bgTaskService.shutdown();
+
         // capture the registered ComponentCallbacks
         verify(context, times(1)).registerComponentCallbacks(componentCallbacksCaptor.capture());
 

bugsnag-android-core/src/main/java/com/bugsnag/android/Client.java

@@ -71,11 +71,11 @@ public class Client implements MetadataAware, CallbackAware, UserAware {
 
     final SessionTracker sessionTracker;
 
-    private final SystemBroadcastReceiver systemBroadcastReceiver;
+    final SystemBroadcastReceiver systemBroadcastReceiver;
     private final ActivityBreadcrumbCollector activityBreadcrumbCollector;
     private final SessionLifecycleCallback sessionLifecycleCallback;
 
-    private final Connectivity connectivity;
+    final Connectivity connectivity;
 
     @Nullable
     private final StorageManager storageManager;
@@ -220,24 +220,23 @@ public Unit invoke(String activity, Map<String, ?> metadata) {
             exceptionHandler.install();
         }
 
-        // register a receiver for automatic breadcrumbs
-        systemBroadcastReceiver = SystemBroadcastReceiver.register(this, logger, bgTaskService);
-        registerComponentCallbacks();
-
         // load last run info
         lastRunInfoStore = new LastRunInfoStore(immutableConfig);
         lastRunInfo = loadLastRunInfo();
 
         // initialise plugins before attempting to flush any errors
         loadPlugins(configuration);
 
-        connectivity.registerForNetworkChanges();
-
         // Flush any on-disk errors and sessions
         eventStore.flushOnLaunch();
         eventStore.flushAsync();
         sessionTracker.flushAsync();
 
+        // register listeners for system events in the background.
+        systemBroadcastReceiver = new SystemBroadcastReceiver(this, logger);
+        registerComponentCallbacks();
+        registerListenersInBackground();
+
         // leave auto breadcrumb
         Map<String, Object> data = Collections.emptyMap();
         leaveAutoBreadcrumb("Bugsnag loaded", BreadcrumbType.STATE, data);
@@ -296,6 +295,25 @@ public Unit invoke(String activity, Map<String, ?> metadata) {
         this.exceptionHandler = exceptionHandler;
     }
 
+    /**
+     * Registers listeners for system events in the background. This offloads work from the main
+     * thread that collects useful information from callbacks, but that don't need to be done
+     * immediately on client construction.
+     */
+    void registerListenersInBackground() {
+        try {
+            bgTaskService.submitTask(TaskType.DEFAULT, new Runnable() {
+                @Override
+                public void run() {
+                    connectivity.registerForNetworkChanges();
+                    SystemBroadcastReceiver.register(appContext, systemBroadcastReceiver, logger);
+                }
+            });
+        } catch (RejectedExecutionException ex) {
+            logger.w("Failed to register for system events", ex);
+        }
+    }
+
     private LastRunInfo loadLastRunInfo() {
         LastRunInfo lastRunInfo = lastRunInfoStore.load();
         LastRunInfo currentRunInfo = new LastRunInfo(0, false, false);