递归组装Cascader 级联选择器和Tree 树形控件结构的数据

我就是我 2022-04-13 15:08 551阅读 0赞

以商品分类表为例,重点看分类ID和父分类ID

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5OTQwMjA1_size_16_color_FFFFFF_t_70][]

public List<Map<String,Object>> getGoodsCategoryTree() {
            //1.获取所有商品分类,条件:category_id!=0(0为顶级菜单的父类ID)和disabled=0(删除标记为正常)
            List<GoodsCategoryEntity> goodsCategoryList = this.baseMapper.selectList(new EntityWrapper<GoodsCategoryEntity>()
                    .ne("category_id", 0)
                    .eq("disabled", 0));
            //2.调用生成tree结构数据的方法,参数是所有商品分类和顶级菜单父类ID
            List<Map<String,Object>> categoryTree = categoryTreeHandle(goodsCategoryList, 0);
            return categoryTree;
        }

private List<Map<String,Object>> categoryTreeHandle(List<GoodsCategoryEntity> categoryEntityList, int pid) {
            List<Map<String,Object>> resultList = new ArrayList<>();
    
            //获取顶级元素集合
            Integer parentId;
            for (GoodsCategoryEntity goodsCategory : categoryEntityList) {
                parentId = goodsCategory.getParentCategoryId();
                if (pid == parentId) {
                    Map map = new HashMap();
                    map.put("label", goodsCategory.getCategoryName());
                    map.put("value", goodsCategory.getCategoryId());
                    resultList.add(map);
                }
            }
    
            //获取每个顶层元素的子数据集合
            for (Map map : resultList) {
                int value = Integer.parseInt(map.get("value").toString());
                List<Map<String,Object>> temp = categoryTreeHandle(categoryEntityList, value);
                if (temp.size() > 0) {
                    map.put("children", temp);
                }
            }
            return resultList;
        }

页面接收到的数据效果

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5OTQwMjA1_size_16_color_FFFFFF_t_70 1][]

主要是应用递归遍历出父节点下的所有子节点

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM5OTQwMjA1_size_16_color_FFFFFF_t_70 1]: /images/20220413/47adb3083f4b437886c1fa8f95fcc5b7.png