Android : android - Alert Dialog + intent

public void screen2 (View view) {

    final AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("screen2");
    builder.setMessage("go to screen2?");

    builder.setPositiveButton("yes", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int id) {
            Intent intent = new Intent(this,Screen2Activity.class);
            startActivity(intent);

        }

I want to start an activity from an AlertDialog but i found an error on "Intent intent = new Intent(this,Tela2Activity.class);"

ANY HELP??