Is it a good practice to save activity instance in a WeakReference

Question

Here, in this answer Activity instance is saved in WeakReference<Activity> variable. So that it will avoid memory leaks. Is it a good practice to do so?

public class BackgroundService extends IntentService {
    private static WeakReference<Activity> mActivityRef; 

    public static void updateActivity(Activity activity) {
        mActivityRef = new WeakReference<>(activity);
    }
}

I'm using mActivityRef.get() and casting it to required activity object. Using that object, accessing the methods in activity.

The purpose is to access Activity methods from service, this code does the work but as per the comments I'm confused whether to use it or not

I've referred the document yet not clear.

Answer 1

Is it a good practice to do so?

No.

The purpose is to access Activity methods from service

That activity may not exist. For example, the user could press BACK and destroy the activity while the service is running. Calling methods on a destroyed activity will likely lead to crashes.

Use an event bus (LocalBroadcastManager, greenrobot's EventBus, etc.) for loosely-coupled communications between components, such as between services and activities. Have the activity register for events when it is visible, and have the service post events as needed.