The method findViewById(int) is undefined

Question

I\'m new to Android development and I\'m trying to code a little app which allows me to grab an external JSON file and parse it. I got this to work, however it wont work if

Answer 1

The implementation of AsyncTask in one of the other answers is flawed. The progress dialog is being created every time within publishProgress, and the reference to the dialog is not visible outside the method. Here is my attempt:

public class Main extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        new LongOperation().execute();
    }
    class LongOperation extends AsyncTask {
        ProgressDialog pd = null;
        TextView tv = null;

        @Override
        protected void onPreExecute(){
            tv = Main.this.findViewById(R.id.textvewid);
            pd = new ProgressDialog(Main.this);
            pd.setMessage("Working...");
            // setup rest of progress dialog
        }
        @Override
        protected String doInBackground(String... params) {
            //perform existing background task
            return result;
        }
        @Override
        protected void onPostExecute(String result){
            pd.dismiss();
            tv.setText(result);
        }
    }
}