Question

I have two activities – one displays data from SQLite, and the other adds data there. I can switch between them with tabs. The problem is that if I add a new item I don’t know how to refresh the list, because it’s in a different activity class and I can’t access it in my adding class. How can this be solved?

Here is my two classes:

List:

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_1);

    final ShoppingSQL shoppingSQL = new ShoppingSQL(this);
    final List<ShoppingData> list = shoppingSQL.getAll();

    final ArrayAdapter<ShoppingData> adapter = new ArrayAdapter<ShoppingData>(
            this, android.R.layout.simple_list_item_1, list);
    setListAdapter(adapter);

    this.getListView().setLongClickable(true);
       this.getListView().setOnItemLongClickListener(new OnItemLongClickListener() {
            public boolean onItemLongClick(AdapterView<?> parent, View v, int position, long id) {
                shoppingSQL.delete((int)list.get(position).getId());
                adapter.remove(list.get(position));
                adapter.notifyDataSetChanged();
                return true;
            }
        });
}

Add:

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_2);
}

public void ButtonOnClick(View v) {
    ShoppingSQL shoppingSQL = new ShoppingSQL(this);

    ShoppingData data = new ShoppingData();
    data.setName("test");

    shoppingSQL.add(data);

    Dialog d = new Dialog(this);
    d.setTitle("Added!");
    d.show();
}

I also have a little sidequestion. In my first (list) activity, Eclipse made every variable final when I accessed them in “onLongClick” – why is that and can that be avoided? Also any comment on what I should look in to as well and make my code better or any other mistakes I made would be very good.

Answer 1

I’d keep it simple. Just send an intent from Add class to List class and then your list will be populated again with new items.