android - 如何在 GridLayoutManager 中准备 setSpanSizeLookup

Question

我需要每个 18,36,54,...18*Nth... 网格布局，宽度：匹配父级和高度：网格布局管理器中的 60dp 用于分页加载栏目的。

这是我的代码，

 GridLayoutManager mng_layout = new GridLayoutManager(this, 4);//WHAT IS 4 ?//
            mng_layout.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
                @Override
                public int getSpanSize(int position) {
                    int mod = position % 6;   //WHAT IS 6 ?//
    
                    if (position == 0 || position == 1)
                        return 2;    //WHAT IS 2 ?//
                    else if (position < 6)
                        return 1;   //WHAT IS 1 ?//
                    else if (mod == 0 || mod == 1)
                        return 2;   //WHAT IS 2 ?//
                    else
                        return 1;   //WHAT IS 1 ?//
                }
            }); 

如果有人有时间，请解释代码中的注释行

标签： androidandroid-recyclerviewgridlayoutmanager

Answer 1

跨度大小表示此项目从网格中占用多少个单元格

public int getSpanSize(int position) {
                int mod = position % 6;   //here 18%6=0 ,19%6=1 ,36%6=0 ,37%6=1 and so one    
                if (position == 0 || position == 1)
                    return 2;    // if this is the first or sesond items make it take span size of 2 so 4/2 =2 cells will be shows
                else if (position < 6)
                    return 1;   // here 2,3,4,5 < 6 so every item should take span size 1 out of 4 , so we have 4 cells 
                else if (mod == 0 || mod == 1)
                    return 2;   // here we check the mode which is defined above 18,19 & 36,37 ,54,55 and so on every pair will span 2 cells for every number 
                else
                    return 1;   // any thing other like  will take one span out of 4 grid columns 
            }
        }

你可以看看这个教程