MainActivity.this is not an enclosing class AsyncTask

Eclipse is probably right, and you are trying to access a class (MainActivity) that is inside it's own file from another class that is in its own file (BackgroundWorker) . There is no way to do that - how is one class supposed to know about the other's instance magically? What you can do:

• Move the AsyncTask so it is an inner class in MainActivity
• Pass off your Activity to the AsyncTask (via its constructor) then acess using activityVariable.findViewById(); (I am using mActivity in the example below) Alternatively, your ApplicationContext (use proper naming convention, the A needs to be lowercase) is actually an instance of MainActivity you're good to go, so do ApplicationContext.findViewById();

Using the Constructor example:

public class BackgroundWorker extends AsyncTask<Context, String, ArrayList<Card>>
{
    Context ApplicationContext;
    Activity mActivity;

   public BackgroundWorker (Activity activity)
   {
     super();
     mActivity = activity;
   }

//rest of code...

As for

I'm not sure if I used the right way to get the context

It is fine.