RecyclerViewTabLayout

页面布局，采用CoordinatorLayout嵌套Recyclerview,TabLayout吸顶。和支付宝页面类似
内容区域采取嵌套Recyclerview的方式，复用同一个ViewPool

仿支付宝“全部应用”模块，联动布局

解决scrollToPositionWithOffset没有滚动动画的问题
解决偶现点击TabLayout RecyclerView不滚动的问题
RecyclerView滑动过程TabLayout平滑滚动动画
动态计算最后一个item空白高度

TabLayout平滑滚动动画

 LinearLayoutManager layoutManager =(LinearLayoutManager)recyclerView.getLayoutManager();
 Tab tabAt = mTabLayout.getTabAt(layoutManager.findFirstVisibleItemPosition());
 if (tabAt != null && !tabAt.isSelected()) {
    tabAt.select();
 }

TabLayout点击item是有动画， mTabLayout.setScrollPosition() 这个方法没有动画。

scrollToPositionWithOffset没有滚动动画的问题

//平滑移动但是，只要那一项现在看得到了，那它就罢工了 mRecyclerView.smoothScrollToPosition(position); //直接requestLayout，没有动画 mLinearLayoutManager.scrollToPositionWithOffset(position, 0);

解决办法使用 SmoothScroller 移动到指定位置

创建SmoothScroller RecyclerView.SmoothScroller mSmoothScroller = new LinearSmoothScroller(context) { @Override protected int getVerticalSnapPreference() { return LinearSmoothScroller.SNAP_TO_START; } };
移动到想要的位置 mSmoothScroller.setTargetPosition(position); mLinearLayoutManager.startSmoothScroll(mSmoothScroller);

动态计算最后一个空白item高度

     @Override
        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            if (viewType == VIEW_TYPE_ITEM) {
                final View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.demo_item, parent, false);
                return new ItemViewHolder(view);
            } else {
                //Footer是最后留白的位置，以便最后一个item能够出发tab的切换
                View view = new View(parent.getContext());
                Log.e("footer", "parentHeight: " + mRecyclerViewHeight + "--" + "itemHeight: " + itemHeight);
                view.setLayoutParams(
                        new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
                                mRecyclerViewHeight - itemHeight));
                return new FooterViewHolder(view);
            }
        }

        @Override
        public void onBindViewHolder(RecyclerView.ViewHolder holder, final int position) {
            if (holder.getItemViewType() == VIEW_TYPE_ITEM) {
                final ItemViewHolder itemViewHolder = (ItemViewHolder) holder;
                itemViewHolder.mTitle.setText(mData.get(position).name);
                RecyclerView recyclerView = itemViewHolder.mRecyclerView;
                recyclerView.setRecycledViewPool(mRecycledViewPool);
                recyclerView.setHasFixedSize(false);
                recyclerView.setNestedScrollingEnabled(false);
                recyclerView.setLayoutManager(new LinearLayoutManager(recyclerView.getContext()) {
                    @Override
                    public boolean canScrollVertically() {
                        return false;
                    }

                    @Override
                    public void onLayoutCompleted(State state) {
                        super.onLayoutCompleted(state);
                        // 由于内部采取的Recyclerview嵌套的方式。直接post获取高度不准确。 
                        mRecyclerViewHeight = mRecyclerView.getHeight();
                        itemHeight = itemViewHolder.itemView.getHeight();
                        Log.e("onLayoutCompleted",
                                "itemHeight: " + itemHeight + "--" + position);
                    }
                });
                DemoAdapter demoAdapter = new DemoAdapter(mData.get(position).mSubItems);
                recyclerView.setAdapter(demoAdapter);

            }
        }

解决偶现点击TabLayout RecyclerView不滚动的问题

加入FixAppBarLayoutBehavior解决问题

Cornflower1991 / RecyclerViewTabLayout