RecyclerView指定布局管理器

//listview

recyclerView.setLayoutManager(new LinearLayoutManager(FirstActivity.this,LinearLayoutManager.VERTICAL,false));

//GridView

 recyclerView.setLayoutManager(new GridLayoutManager(FirstActivity.this,3));

//横向单行

  recyclerView.setLayoutManager(new LinearLayoutManager(FirstActivity.this,LinearLayoutManager.HORIZONTAL,false));

//横向多行

 recyclerView.setLayoutManager(new GridLayoutManager(FirstActivity.this,3, OrientationHelper.HORIZONTAL,false));

//瀑布

 recyclerView.setLayoutManager(new StaggeredGridLayoutManager(3, OrientationHelper.VERTICAL));