我有一个关于如何使用RecyclerView进行分页的非常详细的示例。在高层次，我有一个设置PAGE_SIZE，让我们说30。所以我请求30个项目，如果我得到30个，我就请求下一页。如果我得到的条目少于30个，我就标记一个变量来指示已经到达最后一页，然后停止请求更多的页面。看看吧，告诉我你的想法。

https://medium.com/@etiennelawlor/pagination-with-recyclerview-1cb7e66a502b

有一个方法public void setOnScrollListener (RecyclerView。OnScrollListener监听器)在https://developer.android.com/reference/android/support/v7/widget/RecyclerView.html#setOnScrollListener%28android.support.v7.widget.RecyclerView.OnScrollListener%29。使用这个

编辑:

在onScrollListener中重写onScrollStateChanged方法并执行此操作

            boolean loadMore = firstVisibleItem + visibleItemCount >= totalItemCount;

            //loading is used to see if its already loading, you have to manually manipulate this boolean variable
            if (loadMore && !loading) {
                 //end of list reached
            }

我已经创建LoadMoreRecyclerView使用Abdulaziz Noor回答

LoadMoreRecyclerView

public class LoadMoreRecyclerView extends RecyclerView  {

    private boolean loading = true;
    int pastVisiblesItems, visibleItemCount, totalItemCount;
    //WrapperLinearLayout is for handling crash in RecyclerView
    private WrapperLinearLayout mLayoutManager;
    private Context mContext;
    private OnLoadMoreListener onLoadMoreListener;

    public LoadMoreRecyclerView(Context context) {
        super(context);
        mContext = context;
        init();
    }

    public LoadMoreRecyclerView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        mContext = context;
        init();
    }

    public LoadMoreRecyclerView(Context context, @Nullable AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        mContext = context;
        init();
    }

    private void init(){
        mLayoutManager = new WrapperLinearLayout(mContext,LinearLayoutManager.VERTICAL,false);
        this.setLayoutManager(mLayoutManager);
        this.setItemAnimator(new DefaultItemAnimator());
        this.setHasFixedSize(true);
    }

    @Override
    public void onScrolled(int dx, int dy) {
        super.onScrolled(dx, dy);

        if(dy > 0) //check for scroll down
        {
            visibleItemCount = mLayoutManager.getChildCount();
            totalItemCount = mLayoutManager.getItemCount();
            pastVisiblesItems = mLayoutManager.findFirstVisibleItemPosition();

            if (loading)
            {
                if ( (visibleItemCount + pastVisiblesItems) >= totalItemCount)
                {
                    loading = false;
                    Log.v("...", "Call Load More !");
                    if(onLoadMoreListener != null){
                        onLoadMoreListener.onLoadMore();
                    }
                    //Do pagination.. i.e. fetch new data
                }
            }
        }
    }

    @Override
    public void onScrollStateChanged(int state) {
        super.onScrollStateChanged(state);
    }

    public void onLoadMoreCompleted(){
        loading = true;
    }

    public void setMoreLoading(boolean moreLoading){
        loading = moreLoading;
    }

    public void setOnLoadMoreListener(OnLoadMoreListener onLoadMoreListener) {
        this.onLoadMoreListener = onLoadMoreListener;
    }
}

WrapperLinearLayout

public class WrapperLinearLayout extends LinearLayoutManager
{
    public WrapperLinearLayout(Context context, int orientation, boolean reverseLayout) {
        super(context, orientation, reverseLayout);
    }

    @Override
    public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {
        try {
            super.onLayoutChildren(recycler, state);
        } catch (IndexOutOfBoundsException e) {
            Log.e("probe", "meet a IOOBE in RecyclerView");
        }
    }
}

//在xml中添加

<your.package.LoadMoreRecyclerView
    android:id="@+id/recycler_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
</your.package.LoadMoreRecyclerView>

OnCreate或onViewCreated

mLoadMoreRecyclerView = (LoadMoreRecyclerView) view.findViewById(R.id.recycler_view);
mLoadMoreRecyclerView.setOnLoadMoreListener(new OnLoadMoreListener() {
            @Override
            public void onLoadMore() {
                callYourService(StartIndex);
            }
        });

callYourService

private void callYourService(){
    //callyour Service and get response in any List

    List<AnyModelClass> newDataFromServer = getDataFromServerService();
    //Enable Load More
    mLoadMoreRecyclerView.onLoadMoreCompleted();

    if(newDataFromServer != null && newDataFromServer.size() > 0){
            StartIndex += newDataFromServer.size();

            if (newDataFromServer.size() < Integer.valueOf(MAX_ROWS)) {
                    //StopLoading..
                   mLoadMoreRecyclerView.setMoreLoading(false);
            }
    }
    else{
            mLoadMoreRecyclerView.setMoreLoading(false);
            mAdapter.notifyDataSetChanged();
    }
}

我使用了recyclerview。adapter的onBindViewHolder方法。

适配器:

public interface OnViewHolderListener {
    void onRequestedLastItem();
}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {

    ...

    if (position == getItemCount() - 1) onViewHolderListener.onRequestedLastItem();
}

片段(或活动):

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    contentView = inflater.inflate(R.layout.comments_list, container, false);
    recyclerView = (RecyclerView) mContentView.findViewById(R.id.my_recycler_view);
    adapter = new Adapter();
    recyclerView.setAdapter(adapter);

    ...

    adapter.setOnViewHolderListener(new Adapter.OnViewHolderListener() {
        @Override
        public void onRequestedLastItem() {
            //TODO fetch new data from webservice
        }
    });
    return contentView;
}

下面是一个简单实现无尽滚动RecyclerView的例子，使用一个从各种来源编译的简单库。

在build.gradle中添加这一行

implementation 'com.hereshem.lib:awesomelib:2.0.1'

在活动中创建RecyclerView布局

<com.hereshem.lib.recycler.MyRecyclerView
        android:id="@+id/recycler"
        app:layoutManager="LinearLayoutManager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

通过传递ViewHolder支持的类来创建一个ViewHolder

public static class EVHolder extends MyViewHolder<Events> {
    TextView date, title, summary;
    public EVHolder(View v) {
        super(v);
        date = v.findViewById(R.id.date);
        title = v.findViewById(R.id.title);
        summary = v.findViewById(R.id.summary);
    }
    @Override
    public void bindView(Events c) {
        date.setText(c.date);
        title.setText(c.title);
        summary.setText(c.summary);
    }
}

通过在适配器中传递项目、类和布局来创建项目列表变量和很少行的适配器

List<Events> items = new ArrayList<>();
MyRecyclerView recycler = findViewById(R.id.recycler);
RecyclerViewAdapter adapter = new RecyclerViewAdapter(this, items, EVHolder.class, R.layout.row_event);
recycler.setAdapter(adapter);

ClickListener和LoadMore Listener可以通过以下几行添加

recycler.setOnItemClickListener(new MyRecyclerView.OnItemClickListener() {
    @Override
    public void onItemClick(int position) {
        Toast.makeText(MainActivity.this, "Recycler Item Clicked " + position, Toast.LENGTH_SHORT).show();
    }
});

recycler.setOnLoadMoreListener(new MyRecyclerView.OnLoadMoreListener() {
    @Override
    public void onLoadMore() {
        loadData();
    }
});
loadData();

数据加载后必须调用此函数

recycler.loadComplete();

当不需要LoadMore时，可以通过调用LoadMore来隐藏布局

recycler.hideLoadMore();

更多的例子可以在这里找到

希望这对你有所帮助。

对于那些只想在最后一项完全显示时得到通知的人，可以使用view . canscrollvertical()。

这是我的实现:

public abstract class OnVerticalScrollListener
        extends RecyclerView.OnScrollListener {

    @Override
    public final void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        if (!recyclerView.canScrollVertically(-1)) {
            onScrolledToTop();
        } else if (!recyclerView.canScrollVertically(1)) {
            onScrolledToBottom();
        } else if (dy < 0) {
            onScrolledUp();
        } else if (dy > 0) {
            onScrolledDown();
        }
    }

    public void onScrolledUp() {}

    public void onScrolledDown() {}

    public void onScrolledToTop() {}

    public void onScrolledToBottom() {}
}

注意:如果你想支持API < 14，你可以使用recyclerView.getLayoutManager(). canscrollvertical()。