RecyclerView續，下拉刷新與上拉加載

上次寫了RecyclerView的強大，忘了補充好多個問題，今天全部補上。

首先下拉刷新，這個簡單，所以我也只是簡單說說

我一直都是認為谷歌有自帶的框架就不用第三方，所以當然是用SwipeRefreshLayout來下拉刷新

配置下很簡單

mSwipeRefreshLayout.setOnRefreshListener(mOnRefreshListener);
        mSwipeRefreshLayout.setColorSchemeResources(R.color.status_bar_bg, R.color.orange, R.color.green);

    /**
     * 刷新
     */
    private SwipeRefreshLayout.OnRefreshListener mOnRefreshListener = new SwipeRefreshLayout.OnRefreshListener() {
        @Override
        public void onRefresh() {
            pageNum = 1;
            mAdapter.clearList();//清楚數據，上一篇文章的事
            getData();//獲取數據
        }
    };

官方控件簡簡單單的下拉刷新就完成了

接下來是上拉加載，別人扔給我的控件

mRecyclerView.addOnScrollListener(mOnScrollListener);


    /**
     * RecycleView的滑動監聽(加載更多)
     */
    private EndlessRecyclerOnScrollListener mOnScrollListener = new EndlessRecyclerOnScrollListener() {

        @Override
        public void onLoadNextPage(View view) {
            super.onLoadNextPage(view);
            //下面這是重點，第三個參數是一頁10條（用來控制是否可以繼續下拉），第四個是顯示加載狀態，最后一個可以配置點擊重試請求網絡
            RecyclerViewStateUtils.setFooterViewState(Activity.this, mRecyclerView, 10, LoadingFooter.State.Loading, null);
            pageNum++;
            getData();
        }
    };

那個設置狀態的幾種類型：

RecyclerViewStateUtils.setFooterViewState(mRecyclerView, LoadingFooter.State.Normal); //加載完成后不顯示的正常狀態

RecyclerViewStateUtils.setFooterViewState(mRecyclerView, LoadingFooter.State.TheEnd);//沒有下一頁的狀態

 RecyclerViewStateUtils.setFooterViewState(Activity.this, mRecyclerView, 10, LoadingFooter.State.Loading, null);//加載狀態

接著上EndlessRecyclerOnScrollListener

public class RecyclerViewStateUtils {

    /**
     * 設置headerAndFooterAdapter的FooterView State
     *
     * @param instance      context
     * @param recyclerView  recyclerView
     * @param pageSize      分頁展示時，recyclerView每一頁的數量
     * @param state         FooterView State
     * @param errorListener FooterView處于Error狀態時的點擊事件
     */
    public static void setFooterViewState(Activity instance, RecyclerView recyclerView, int pageSize, LoadingFooter.State state, View.OnClickListener errorListener) {

        if(instance==null || instance.isFinishing()) {
            return;
        }

        RecyclerView.Adapter outerAdapter = recyclerView.getAdapter();

        if (outerAdapter == null || !(outerAdapter instanceof HeaderAndFooterRecyclerViewAdapter)) {
            return;
        }

        HeaderAndFooterRecyclerViewAdapter headerAndFooterAdapter = (HeaderAndFooterRecyclerViewAdapter) outerAdapter;

        //只有一頁的時候，就別加什么FooterView了
        if (headerAndFooterAdapter.getInnerAdapter().getItemCount() < pageSize) {
            return;
        }

        LoadingFooter footerView;

        //已經有footerView了
        if (headerAndFooterAdapter.getFooterViewsCount() > 0) {
            footerView = (LoadingFooter) headerAndFooterAdapter.getFooterView();
            footerView.setState(state);

            if (state == LoadingFooter.State.NetWorkError) {
                footerView.setOnClickListener(errorListener);
            }
            recyclerView.scrollToPosition(headerAndFooterAdapter.getItemCount() - 1);
        } else {
            footerView = new LoadingFooter(instance);
            footerView.setState(state);

            if (state == LoadingFooter.State.NetWorkError) {
                footerView.setOnClickListener(errorListener);
            }

            headerAndFooterAdapter.addFooterView(footerView);
            recyclerView.scrollToPosition(headerAndFooterAdapter.getItemCount() - 1);
        }
    }

    /**
     * 獲取當前RecyclerView.FooterView的狀態
     *
     * @param recyclerView
     */
    public static LoadingFooter.State getFooterViewState(RecyclerView recyclerView) {

        RecyclerView.Adapter outerAdapter = recyclerView.getAdapter();
        if (outerAdapter != null && outerAdapter instanceof HeaderAndFooterRecyclerViewAdapter) {
            if (((HeaderAndFooterRecyclerViewAdapter) outerAdapter).getFooterViewsCount() > 0) {
                LoadingFooter footerView = (LoadingFooter) ((HeaderAndFooterRecyclerViewAdapter) outerAdapter).getFooterView();
                return footerView.getState();
            }
        }

        return LoadingFooter.State.Normal;
    }

    /**
     * 設置當前RecyclerView.FooterView的狀態
     *
     * @param recyclerView
     * @param state
     */
    public static void setFooterViewState(RecyclerView recyclerView, LoadingFooter.State state) {
        RecyclerView.Adapter outerAdapter = recyclerView.getAdapter();
        if (outerAdapter != null && outerAdapter instanceof HeaderAndFooterRecyclerViewAdapter) {
            if (((HeaderAndFooterRecyclerViewAdapter) outerAdapter).getFooterViewsCount() > 0) {
                LoadingFooter footerView = (LoadingFooter) ((HeaderAndFooterRecyclerViewAdapter) outerAdapter).getFooterView();
                footerView.setState(state);
            }
        }
    }
}

好了上拉加載完成了

建議：加載的時候可以清楚上拉加載的監聽，完成了，確定不是最后一頁了再加上

mRecyclerView.clearOnScrollListeners();
mRecyclerView.addOnScrollListener(mOnScrollListener);

來自：http://www.jianshu.com/p/7fde3ec5a23e