服务内的 startActivity 不适用于所有 Android 设备

Question

I have to start an activity from FirebaseMessagingService and I invoke the following code when I receive a notification

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    // some code here...

    Intent intent = new Intent(this, MyActivity.class);
    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivity(intent);
}

When the app is in background and I receive a notification the result was

Xiaomi mi a2: MyActivity has been launched successfully.

Xiaomi redmi note 7: MyActivity not launched and nothing happened even not crashing.

Any help why starActivity is no working on all devices inside a background service, and how can I fix this issue?

Answer 1

So you want the user to still receive messages after the app has been killed - you can try using background services but since Android 10 bans background services as CommonsWare mentioned, and versions 8 & 9 both will kill background services after some time, you shouldn't rely on onMessageReceived when the app is killed. Instead, look into Firebase's NotificationMessage docs

NotificationMessage is sent to the user and received no matter whether the device is in Doze mode or the app has been killed. This is probably the solution you're looking for - keeping background services running in Android 8+ is going to be difficult, and impossible in newer versions.