public class Fragment2 extends Fragment {

@Override public View onCreateView(LayoutInflater inflater,  ViewGroup container,  Bundle savedInstanceState) {     return  inflater.inflate(R.layout.fragment2,container,false); } @Override public void onStart() {     super.onStart();     SeekBar seekbar1 = (SeekBar) getActivity().findViewById(R.id.seekbar1);     seekbar1.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {         @Override         public void onProgressChanged(SeekBar seekBar, int progress, boolean b) {              }          @Override         public void onStartTrackingTouch(SeekBar seekBar) {          }          @Override         public void onStopTrackingTouch(SeekBar seekBar) {          }      }); } 

}

public class MainActivity extends FragmentActivity {

private FragmentManager manager; private FragmentTransaction transaction;  @Override public void onCreate( Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);      manager = getSupportFragmentManager();     initFragment2(); }  private void initFragment2() {     transaction = manager.beginTransaction();     transaction.add(R.id.conteiner, new Fragment2());     transaction.commit(); } 

}