Android Fragment的标準寫法

**
 * 一個簡單的Fragment子類
 * 含有這個Master_Fragment的Activity必須要去 實作 Master_Fragment.OnFragmentInteractionListener
 * 這個接口來處理Fragment與Activity的互動事件
 * 這裡強烈建議使用工廠方法Master_Fragment#newInstance
 * 來創造Master_Fragment的執行個體.
 */
public class Master_Fragment extends Fragment {
    // 名字根據實際需求進行更改
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    // 這裡的參數隻是一個舉例可以根據需求更改
    private String mParam1;
    private String mParam2;

    private OnFragmentInteractionListener mListener;

    /**
     * 通過工廠方法來建立Fragment執行個體
     * 同時給Fragment來提供參數來使用
     *
     * @param param1 參數1.
     * @param param2 參數2.
     * @return Master_Fragment的執行個體.
     */
    public static Master_Fragment newInstance(String param1, String param2) {
        Master_Fragment fragment = new Master_Fragment();
        Bundle args = new Bundle();
        args.putString(ARG_PARAM1, param1);
        args.putString(ARG_PARAM2, param2);
        fragment.setArguments(args);
        return fragment;
    }

    public Master_Fragment() {
        // Required empty public constructor
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            mParam1 = getArguments().getString(ARG_PARAM1);
            mParam2 = getArguments().getString(ARG_PARAM2);
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_master_, container, false);
    }

    // TODO: Rename method, update argument and hook method into UI event
    public void onButtonPressed(Uri uri) {
        if (mListener != null) {
            mListener.onFragmentInteraction(uri);
        }
    }


    /**
     *onAttach中連接配接監聽接口 確定Activity支援該接口
     */
    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        try {
            mListener = (OnFragmentInteractionListener) activity;
        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString()
                    + " must implement OnFragmentInteractionListener");
        }
    }

    /**
     * onDetach中登出接口
     */
    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }

    /**
     * 這個互動接口必須被含有Master_Fragment 的Activity繼承
     * 來實作Fragment與Activity直接的互通
     * 更多資訊請參考
     * "http://developer.android.com/training/basics/fragments/communicating.html"
     * >Communicating with Other Fragments</a> .
     */
    public interface OnFragmentInteractionListener {
        // 根據實際需求更改
        public void onFragmentInteraction(Uri uri);
    }

}
           

注意的點

1. 推薦使用newInstance工廠方法來生成Fragment的執行個體
2. Activity和Fragment直接的互通使用回調接口完成
3. onAttach中監聽接口，在onDetach中登出接口