/**

 * Fragment 加载网络请求

 */

public abstract class BaseLoadDataForNetFragment extends Fragment {

    // 视图是否初始化完成

    protected boolean isViewInitiated;

    // 界面是否可见

    protected boolean isVisibleToUser;

    // 数据是否加载

    protected boolean isDataInitiated;

    @Override

    public void onActivityCreated(Bundle savedInstanceState) {

        super.onActivityCreated(savedInstanceState);

        isViewInitiated = true;

        prepareFetchData();

    }

    @Override

    public void setUserVisibleHint(boolean isVisibleToUser) {

        super.setUserVisibleHint(isVisibleToUser);

        this.isVisibleToUser = isVisibleToUser;

        prepareFetchData();

    }

    private void prepareFetchData() {

        // 不设置为需要每次可见的时候都强制刷新界面

        prepareFetchData(false);

    }

    /**

     * 设置true，可强制刷新界面

     *

     * @param forceUpdate 是否强制刷新界面

     * @return

     */

    protected void prepareFetchData(boolean forceUpdate) {

        if (isVisibleToUser && isViewInitiated && (!isDataInitiated || forceUpdate)) {

            fetchDataForNet();

            isDataInitiated = true;

        }

    }

    /**

     * 刷新数据，网络刷新数据

     */

    public abstract void fetchDataForNet();

}

@Nullable

    @Override

    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

        WLog.d("onCreateView");

        View mView = inflater.inflate(R.layout.fragment_my_order, container, false);

        mNoDataTV = (TextView) mView.findViewById(R.id.fragment_order_tv_no_data);

        mShowLoading = (LinearLayout) mView.findViewById(R.id.fragment_order_ll_loading);

        // 子界面可以重用网络加载的数据

        if (isDataInitiated) {

            WLog.d("数据已经加载过...无需再次请求数据");

            //mShowLoading.setVisibility(View.GONE);

            //mNoDataTV.setVisibility(View.VISIBLE);

        }

        return mView;

    }