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可以设置头/底部，Item点击/长按监听的recyclerView。
可利用ExStaggeredGridLayoutManager给瀑布流设置头/底
利用DividerGridItemDecoration或DividerItemDecoration来添加分割线
可利用OnRecyclerViewScrollListener监听滑动到顶部、底部的事件，还可以监听滑动的距离
本项目中demo的adapter用的是通用的adapter（CommonRcvAdapter）来做的，如果你希望用recyclerView的adapter来做，你只需要将自己的adapter继承自BaseRecyclerAdapter即可。如果你希望了解下通用的adapter的构建模式，请参考：https://github.com/tianzhijiexian/CommonAdapter
Jack Tony: <developer_kale@.com>
Copyright 2015 Jack Tony
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