recyclerview 判断滑动到底部

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recyclerview 判断滑动到底部是一种非常常见操作，这里我封装一个类非常方便可以实现底部判断操作。

public class CXLoadMoreListener extends RecyclerView.OnScrollListener {

    private int lastVisibleItem;
    private RecyclerView.Adapter<RecyclerView.ViewHolder> testMovieAdapter;
    private Runnable runnable;
    private LinearLayoutManager linearLayoutManager;

    public CXLoadMoreListener(RecyclerView.Adapter<RecyclerView.ViewHolder> testMovieAdapter, LinearLayoutManager linearLayoutManager, Runnable runnable) {
        this.testMovieAdapter = testMovieAdapter;
        this.runnable = runnable;
        this.linearLayoutManager = linearLayoutManager;
    }

    @Override
    public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
        super.onScrollStateChanged(recyclerView, newState);
        if (newState == RecyclerView.SCROLL_STATE_IDLE && lastVisibleItem + 1 == testMovieAdapter.getItemCount()) {
            if (!isSlideToBottom(recyclerView))//精确判断是否底部
                return;
            if (runnable!=null)
            {
                runnable.run();
            }
        }
    }

    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
        lastVisibleItem=linearLayoutManager.findLastVisibleItemPosition();
    }

    public boolean isSlideToBottom(RecyclerView recyclerView) {
        if (recyclerView == null) return false;
        if (recyclerView.computeVerticalScrollExtent() + recyclerView.computeVerticalScrollOffset()
                >= recyclerView.computeVerticalScrollRange())
            return true;
        return false;
    }

}

下面这个代码是精确判断到底部，如果只需要判断最后一项item 显示可以去掉这个判断。

if (!isSlideToBottom(recyclerView))//精确判断是否底部
                return;

使用方法：

        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(linearLayoutManager);
        recyclerView.addOnScrollListener(new CXLoadMoreListener(adapter, linearLayoutManager, new Runnable() {
            @Override
            public void run() {//底部执行方法
                adapter.changeMoreStatus(CXLoadMoreAdapterHelper.LOAD_MORE);
                adapter.notifyItemChanged(adapter.getItemCount()-1);
                CXUtils.runOnUI(CXConfig.refresh_header_min_time, new Runnable() {
                    @Override
                    public void run() {
                        if (currentIndex>pageSize)
                        {
                            adapter.changeMoreStatus(CXLoadMoreAdapterHelper.NO_MORE);
                            adapter.notifyItemChanged(adapter.getItemCount()-1);
                        }else {
                            requestPLData(false);
                        }
                    }
                });
            }
        }));