Question

MyI don’t understand why I get a compile error for this:

   public class Main_screen extends ListActivity {

       List<Object> completeList;
       private My_ArrayAdapter adapter;


    public void onCreate(Bundle icicle) {
       super.onCreate(icicle);
       completeList = getCompleteList();
       adapter = new My_ArrayAdapter(this, completeList);
       setListAdapter(adapter);
       }

    public void doSth() {
                ...
        }
    }

and in My_ArryAdapter:

 public class My_ArrayAdapter extends ArrayAdapter<Object> {

        private final List<Object> list;
        private final Activity context;


        public My_ArrayAdapter(Activity context, List<Object> list) {
           this.context = context;
           this.list = list;

        }

        public void tryIt() {
           context.doSth();   // <-------- THIS DOES NOT WORK, this method can not be called
        }
    }

Please explain, is there something fundamental I have not understood. I am just passing the context into the ArrayAdapter instance I create. And from within this instance I would like to acccess the caller’s method.

Why shoudl this not be possible?

Many thanks!

Answer 1

try this:

public void tryIt() {
           ((Main_screen)context).doSth();  
        }

context is Activity and it hasn’t doSth(), but Main_screen has, so you should cast to this class