Android RecyclerView使用GridLayoutManager导致间隙变大的问题

我用recyclerView的时候设置LayoutManager为Grid，添加decoration为Grid，作为二级列表时，多次点击一级列表来跳转的时候，两张图之间的间隙在逐渐变大，后来发现是因为多次初始化Adaper的缘故。 

mWaresAdapter = new WaresAdapter(getContext(), datas);
mRecyclerViewWares.setAdapter(mWaresAdapter);
mRecyclerViewWares.setLayoutManager(new GridLayoutManager(getContext(), 2));
mRecyclerViewWares.addItemDecoration(new DividerGridItemDecoration(getContext()));

这是有bug的代码，每次都创建adapter导致间隙变大

解决办法

if(mWaresAdapter == null) {
　　mWaresAdapter = new WaresAdapter(getContext(), datas);  
　　mRecyclerViewWares.setAdapter(mWaresAdapter)
　　mRecyclerViewWares.setLayoutManager(new GridLayoutManager(getContext(), 2)); 
　　mRecyclerViewWares.addItemDecoration(new DividerGridItemDecoration(getContext()));
 }else{
   mWaresAdapter.clearData();
   mWaresAdapter.addData(datas);
 }