Android RecyclerView的LinearSnapHelper与PagerSnapHelper

前言

　　LinearSnapHelper与PagerSnapHelper是一个滑动自动回正的一个辅助类，一般多用于RecyclerView的滚轮选择器的开发上

　　LinearSnapHelper与PagerSnapHelper的区别， LinearSnapHelper多用于一页显示多行内容的线性列表，PagerSnapHelper用于当前只显示一页内容的翻页列表

　　转载请注明来源：https://www.cnblogs.com/guanxinjing/p/16276217.html

LinearSnapHelper的使用

效果图

设置LinearSnapHelper代码

        val provinceLinearSnapHelper = LinearSnapHelper()
        provinceLinearSnapHelper.attachToRecyclerView(mRecyclerView)

监听当前滚动的居中位置，注意是的居中位置

        mRecyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
            override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
                super.onScrollStateChanged(recyclerView, newState)
                if (newState == RecyclerView.SCROLL_STATE_IDLE) {
                    if (recyclerView != null && recyclerView.childCount > 0) {
                        provinceLinearSnapHelper.findSnapView(mBinding.province.layoutManager)?.let {
                            val position = recyclerView.getChildAdapterPosition(it)
                        }
                    }
                }
            }
        })

PagerSnapHelper

设置代码

        val pagerSnapHelper = PagerSnapHelper()
        pagerSnapHelper.attachToRecyclerView(mBinding.province)

End