public class Lewis extends Activity {
    public static final String SHAREPREFERENCE_NAME = "saveData";
    public static final String SHARE_key = "TEST";

    @Override
    protected void onCreate(Bundle state){
       super.onCreate(state);

       //get sharedPreference data
       SharedPreferences settings = getSharedPreferences(SHAREPREFERENCE_NAME,  Context.MODE_PRIVATE);
       String getShareData = settings.getString(SHARE_key, false);

    }

    @Override
    protected void onStop(){
       super.onStop();
      SharedPreferences settings = getSharedPreferences(SHAREPREFERENCE_NAME,  Context.MODE_PRIVATE);
      SharedPreferences.Editor editor = settings.edit();
      editor.putString(SHARE_key, "forTest");
      editor.commit();
    }
}