// in activity 
    setSupportActionBar(toolbar)
    setHasOptionsMenu(true)

    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionBar().setDisplayShowHomeEnabled(true);

    // in fragment 
    
    (activity as AppCompatActivity).setSupportActionBar(view.toolbar)
    setHasOptionsMenu(true)

    ((ActionBarActivity) getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    ((ActionBarActivity) getActivity()).getSupportActionBar().setDisplayShowHomeEnabled(true);



@Override
public boolean onSupportNavigateUp() {
    onBackPressed();
    return true;
}