Your content must have a ListView whose id attribute is 'android.R.id.list'

Question

I have created an xml file like this:

Answer 1

Inherit Activity Class instead of ListActivity you can resolve this problem.

public class ExampleActivity extends Activity  {

    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.mainlist);
    }
}