How fragment get context in Android?

You can use getActivity() , which returns the activity associated with a fragment. The activity is a context (since
Activity extends Context ). You can also override the onAttach() method of fragment:

public static class DummySectionFragment extends Fragment{
...
@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    DBHelper = new DatabaseHelper(activity);
}
}