Inner class can access but not update values – AsyncTask

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How can I ensure that the values remain updated?

They will be updated since they are member variables. However, since AsyncTask is asynchrounous, they might not be updated yet when you check them. You can use an interface to create a callback when these values are updated. This SO answer covers how to do this

Does that mean that any values updated in the new thread will be lost once that thread returns?

No they shouldn’t be “lost”. They probably just haven’t been changed in the AsyncTask when you check them.

Since this isn’t your actual code I can’t see when you are trying to access them but you can use the interface method or call the functions that need these values in onPostExecute(). You also can do a null check before trying to access them. It just depends on the functionality and flow that you need as to which is the best way. Hope that helps.

Edit

In the answer I linked to, you tell the Activity that you will use that interface and override its method(s) with implements AsyncResponse in your Activity declaration after creating the separate interface class

public class MainActivity implements AsyncResponse{

then, in your Activity still, you override the method you declared in that class (void processFinish(String output);)

@Override
 void processFinish(String output){  // using same params as onPostExecute()
 //this you will received result fired from async class of onPostExecute(result) method.
   }

then this is called in onPostExecute() when the listener sees that it is done with delegate.processFinish(result); delegate is an instance of AsyncResponse (your interface class)

    public class AasyncTask extends AsyncTask{
public AsyncResponse delegate=null;

   @Override
   protected void onPostExecute(String result) {
      delegate.processFinish(result);
   }

Interface example taken from linked answer above and adjusted/commented for clarity. So be sure to upvote that answer if it helps anyone.

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