概述：
本三级联动分类服务端使用的是: Springboot + MyBatis-plus，前端使用的是：Vue+ElementUI，树形控件使用的是el-tree。本三级联动分类可以把任一拖拽子项到其它目录，可以添加、编辑、删除分类。
效果图：
实现流程：
一、树形数据展示实现
1、创建表
- cat_id使用bigint类型目的是为了使用雪花算法，加快查询的速度；
- parent_cid父ID，用于子节点指向父亲节点，同理我们可根据当前节点等于子节点点父ID，然后递归，找到所属的所有子节点
- cat_level层级，用于识别当前节点是一级、二级还是三级节点
- show_status是否显示，控制是否显示，使用了逻辑删除功能
- product_unit计量单位，使用什么单位统计当前分类下产品的数量
- product_count产品数量，在添加商品时进行统计更新
- sort排序，进行分类排序
- icon图表，类别的图片，使用iconfont
CREATE TABLE `kmall_product`.`pro_category` (
`cat_id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '分类id',
`name` char(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '分类名称',
`parent_cid` bigint(20) NULL DEFAULT NULL COMMENT '父分类id',
`cat_level` int(4) NULL DEFAULT NULL COMMENT '层级',
`show_status` tinyint(2) NULL DEFAULT NULL COMMENT '是否显示[0-不显示，1显示]',
`sort` int(4) NULL DEFAULT NULL COMMENT '排序',
`icon` char(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '图标地址',
`product_unit` char(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '计量单位',
`product_count` int(11) NULL DEFAULT NULL COMMENT '商品数量',
PRIMARY KEY (`cat_id`) USING BTREE,
INDEX `parent_cid`(`parent_cid`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1433 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci COMMENT = '商品三级分类' ROW_FORMAT = Dynamic;
2、生成实体类
把上面点表内能映射为实体类，便于java中操作
@Data
@TableName("pro_category")
public class CategoryEntity implements Serializable {
private static final long serialVersionUID = 1L;
/**
* 分类id
*/
@TableId
private Long catId;
/**
* 分类名称
*/
private String name;
/**
* 父分类id
*/
private Long parentCid;
/**
* 层级
*/
private Integer catLevel;
/**
* 是否显示[0-不显示，1显示]
*/
@TableLogic(value = "1", delval = "0")
private Integer showStatus;
/**
* 排序
*/
private Integer sort;
/**
* 图标地址
*/
private String icon;
/**
* 计量单位
*/
private String productUnit;
/**
* 商品数量
*/
private Integer productCount;
@JsonInclude(value = JsonInclude.Include.NON_EMPTY)
@TableField(exist = false)
private List<CategoryEntity> children;
}
说明：下面的children是用来保存子节点数据，是暂存在内存中，所以要加上@TableField(exist = false)注解
@JsonInclude(value = JsonInclude.Include.NON_EMPTY)
@TableField(exist = false)
private List<CategoryEntity> children;
3、获取树形数据
创建CategoryController控制层，添加请求方法，使用的是get请求，查询到结果后以data为名称返回给前端
/**
* 查出所有分类以及子分类，以树形结构组装起来
*/
@RequestMapping("/list/tree")
public R listWithTree(){
List<CategoryEntity> entities = categoryService.listWithTree();
return R.ok().put("data", entities);
}
4、查询封装树形数据
创建CategoryServiceImpl实现层，实现listWithTree方法
- 首先查出所有分类
- 选出一级分类
- 递归获取一级分类的所有子节点，设置到children属性中
@Override
public List<CategoryEntity> listWithTree() {
//查出所有分类
List<CategoryEntity> entities = baseMapper.selectList(null);
//组装成父子树形结构
//1级分类
List<CategoryEntity> menus = entities.stream().
filter(entity -> entity.getParentCid() == 0)
.map(entity -> {
entity.setChildren(getChildren(entity, entities));
return entity;
})
.sorted((menu1, menu2) ->
(menu1.getSort() == null ? 0 : menu1.getSort()) -
(menu2.getSort() == null ? 0 : menu2.getSort()))
.collect(Collectors.toList());
return menus;
}
/**
* 递归查找所有菜单的子菜单
*/
private List<CategoryEntity> getChildren(CategoryEntity root, List<CategoryEntity> all) {
List<CategoryEntity> children = all.stream()
.filter(entity -> entity.getParentCid().equals(root.getCatId()))
.map(entity -> {
entity.setChildren(getChildren(entity, all)); //递归设置
return entity;
})
.sorted((menu1, menu2) ->
(menu1.getSort() == null ? 0 : menu1.getSort()) -
(menu2.getSort() == null ? 0 : menu2.getSort()))
.collect(Collectors.toList());
return children;
}
5、前端展现实现
5.1、树形控件el-tree设置
- :data=“menus”：绑定数据menus
- :props=“defaultProps” ：设置默认属性defaultProps，便于与后端数据转换
- expand-on-click-node：设置为false，表示需要单击才展开
- show-checkbox：显示checkbox复选框
- node-key=“catId” ：绑定主键
- :default-expanded-keys=“expandedKey” ：设置默认展开分类
- :draggable=“draggable” ：是否能拖拽节点数据
- :allow-drop=“allowDrop”：拖拽时判定目标节点能否被放置。type 参数有三种情况：‘prev’、‘inner’ 和 ‘next’，分别表示放置在目标节点前、插入至目标节点和放置在目标节点后
- @node-drop=“handleDrop”：拖拽成功完成时触发的事件
<el-tree :data="menus" :props="defaultProps" :expand-on-click-node="false" show-checkbox node-key="catId"
:default-expanded-keys="expandedKey" :draggable="draggable" :allow-drop="allowDrop" @node-drop="handleDrop"
ref="menuTree">
</el-tree>
5.2、树形控件el-tree数据初始化
data() {
return {
pCid: [],
draggable: false,
updateNodes: [],
maxLevel: 0,
title: "",
dialogType: "", //edit,add
category: {
name: "",
parentCid: 0,
catLevel: 0,
showStatus: 1,
sort: 0,
productUnit: "",
icon: "",
catId: null
},
dialogVisible: false,
menus: [],
expandedKey: [],
defaultProps: {
children: "children",
label: "name"
}
};
},
5.3、加载menus数据，绑定到树形控件
说明：/product/category/list/tree此路径对应的是controller里查找树形数据的方法
getMenus() {
this.$http({
url: this.$http.adornUrl("/product/category/list/tree"),
method: "get"
}).then(({
data
}) => {
console.log("成功获取到菜单数据...", data.data);
this.menus = data.data;
});
},
二、添加编辑删除树形控件实现
1、前端添加、编辑、删除实现
1.1、 html内容
- 只有叶子节点才显示删除功能
- 所有的分类都可以编辑
- 只有一级、二级分类有添加功能
<el-button v-if="draggable" @click="batchSave">批量保存</el-button>
<el-button size="mini" type="danger" @click="batchDelete">批量删除</el-button>
<el-tree :data="menus" :props="defaultProps" :expand-on-click-node="false" show-checkbox node-key="catId"
:default-expanded-keys="expandedKey" :draggable="draggable" :allow-drop="allowDrop" @node-drop="handleDrop"
ref="menuTree">
<span class="custom-tree-node" slot-scope="{ node, data }">
<span>{{ node.label }}</span>
<span>
<el-button v-if="node.level <=2" type="text" size="mini" @click="() => append(data)">添加</el-button>
<el-button type="text" size="mini" @click="edit(data)">编辑</el-button>
<el-button v-if="node.childNodes.length==0" type="text" size="mini"
@click="() => remove(node, data)">删除</el-button>
</span>
</span>
</el-tree>
1.2、js实现
- 添加：
append(data) {
console.log("append", data);
this.dialogType = "add";
this.title = "添加分类";
this.dialogVisible = true;
this.category.parentCid = data.catId;
this.category.catLevel = data.catLevel * 1 + 1;
this.category.catId = null;
this.category.name = "";
this.category.icon = "";
this.category.productUnit = "";
this.category.sort = 0;
this.category.showStatus = 1;
},
//添加三级分类
addCategory() {
console.log("提交的三级分类数据", this.category);
this.$http({
url: this.$http.adornUrl("/product/category/save"),
method: "post",
data: this.$http.adornData(this.category, false)
}).then(({
data
}) => {
this.$message({
message: "菜单保存成功",
type: "success"
});
//关闭对话框
this.dialogVisible = false;
//刷新出新的菜单
this.getMenus();
//设置需要默认展开的菜单
this.expandedKey = [this.category.parentCid];
});
},
submitData() {
if (this.dialogType == "add") {
this.addCategory();
}
if (this.dialogType == "edit") {
this.editCategory();
}
},
- 批量添加
batchSave() {
this.$http({
url: this.$http.adornUrl("/product/category/update/sort"),
method: "post",
data: this.$http.adornData(this.updateNodes, false)
}).then(({
data
}) => {
this.$message({
message: "菜单顺序等修改成功",
type: "success"
});
//刷新出新的菜单
this.getMenus();
//设置需要默认展开的菜单
this.expandedKey = this.pCid;
this.updateNodes = [];
this.maxLevel = 0;
});
},
- 编辑
edit(data) {
console.log("要修改的数据", data);
this.dialogType = "edit";
this.title = "修改分类";
this.dialogVisible = true;
//发送请求获取当前节点最新的数据
this.$http({
url: this.$http.adornUrl(`/product/category/info/${data.catId}`),
method: "get"
}).then(({
data
}) => {
//请求成功
console.log("要回显的数据", data);
this.category.name = data.data.name;
this.category.catId = data.data.catId;
this.category.icon = data.data.icon;
this.category.productUnit = data.data.productUnit;
this.category.parentCid = data.data.parentCid;
this.category.catLevel = data.data.catLevel;
this.category.sort = data.data.sort;
this.category.showStatus = data.data.showStatus;
});
},
//修改三级分类数据
editCategory() {
var {
catId,
name,
icon,
productUnit
} = this.category;
this.$http({
url: this.$http.adornUrl("/product/category/update"),
method: "post",
data: this.$http.adornData({
catId,
name,
icon,
productUnit
}, false)
}).then(({
data
}) => {
this.$message({
message: "菜单修改成功",
type: "success"
});
//关闭对话框
this.dialogVisible = false;
//刷新出新的菜单
this.getMenus();
//设置需要默认展开的菜单
this.expandedKey = [this.category.parentCid];
});
},
- 删除单个节点
remove(node, data) {
var ids = [data.catId];
this.$confirm(`是否删除【${data.name}】菜单?`, "提示", {
confirmButtonText: "确定",
cancelButtonText: "取消",
type: "warning"
})
.then(() => {
this.$http({
url: this.$http.adornUrl("/product/category/delete"),
method: "post",
data: this.$http.adornData(ids, false)
}).then(({
data
}) => {
this.$message({
message: "菜单删除成功",
type: "success"
});
//刷新出新的菜单
this.getMenus();
//设置需要默认展开的菜单
this.expandedKey = [node.parent.data.catId];
});
})
.catch(() => {});
console.log("remove", node, data);
}
- 批量删除
batchDelete() {
let catIds = [];
let checkedNodes = this.$refs.menuTree.getCheckedNodes();
console.log("被选中的元素", checkedNodes);
for (let i = 0; i < checkedNodes.length; i++) {
catIds.push(checkedNodes[i].catId);
}
this.$confirm(`是否批量删除【${catIds}】菜单?`, "提示", {
confirmButtonText: "确定",
cancelButtonText: "取消",
type: "warning"
})
.then(() => {
this.$http({
url: this.$http.adornUrl("/product/category/delete"),
method: "post",
data: this.$http.adornData(catIds, false)
}).then(({
data
}) => {
this.$message({
message: "菜单批量删除成功",
type: "success"
});
this.getMenus();
});
})
.catch(() => {});
},
2、服务端添加、编辑、删除实现
- 添加
@RequestMapping("/save")
public R save(@RequestBody CategoryEntity category){
categoryService.save(category);
return R.ok();
}
- 编辑
@RequestMapping("/info/{catId}")
public R info(@PathVariable("catId") Long catId){
CategoryEntity category = categoryService.getById(catId);
return R.ok().put("data", category);
}
@RequestMapping("/update")
public R update(@RequestBody CategoryEntity category){
categoryService.updateCascade(category);
return R.ok();
}
- 删除
@RequestMapping("/delete")
public R delete(@RequestBody Long[] catIds){
//1.检查当前删除的分类，是否被别的地方引用
categoryService.removeMenuByIds(Arrays.asList(catIds));
return R.ok();
}
@Override
public void removeMenuByIds(List<Long> asList) {
//逻辑删除
baseMapper.deleteBatchIds(asList);
}
三、树形控件拖拽功能实现
1、前端实现
1.1、html部分，添加拖拽控制开关
<el-switch v-model="draggable" active-text="开启拖拽" inactive-text="关闭拖拽"></el-switch>
<el-button v-if="draggable" @click="batchSave">批量保存</el-button>
<el-button size="mini" type="danger" @click="batchDelete">批量删除</el-button>
<el-tree :data="menus" :props="defaultProps" :expand-on-click-node="false" show-checkbox node-key="catId"
:default-expanded-keys="expandedKey" :draggable="draggable" :allow-drop="allowDrop" @node-drop="handleDrop"
ref="menuTree">
<span class="custom-tree-node" slot-scope="{ node, data }">
<span>{{ node.label }}</span>
<span>
<el-button v-if="node.level <=2" type="text" size="mini" @click="() => append(data)">添加</el-button>
<el-button type="text" size="mini" @click="edit(data)">编辑</el-button>
<el-button v-if="node.childNodes.length==0" type="text" size="mini"
@click="() => remove(node, data)">Delete</el-button>
</span>
</span>
</el-tree>
1.2、js部分
- 计算可拖拽的信息，找到所有子节点，求出最大深度
allowDrop(draggingNode, dropNode, type) {
//1、被拖动的当前节点以及所在的父节点总层数不能大于3
//1）、被拖动的当前节点总层数
console.log("allowDrop:", draggingNode, dropNode, type);
//
this.countNodeLevel(draggingNode);
//当前正在拖动的节点+父节点所在的深度不大于3即可
let deep = Math.abs(this.maxLevel - draggingNode.level) + 1;
console.log("深度：", deep);
// this.maxLevel
if (type == "inner") {
return deep + dropNode.level <= 3;
} else {
return deep + dropNode.parent.level <= 3;
}
},
countNodeLevel(node) {
//找到所有子节点，求出最大深度
if (node.childNodes != null && node.childNodes.length > 0) {
for (let i = 0; i < node.childNodes.length; i++) {
if (node.childNodes[i].level > this.maxLevel) {
this.maxLevel = node.childNodes[i].level;
}
this.countNodeLevel(node.childNodes[i]);
}
}
},
- 处理拖拽的节点，排序
handleDrop(draggingNode, dropNode, dropType, ev) {
console.log("handleDrop: ", draggingNode, dropNode, dropType);
//1、当前节点最新的父节点id
let pCid = 0;
let siblings = null;
if (dropType == "before" || dropType == "after") {
pCid = dropNode.parent.data.catId == undefined ? 0 : dropNode.parent.data.catId;
siblings = dropNode.parent.childNodes;
} else {
pCid = dropNode.data.catId;
siblings = dropNode.childNodes;
}
this.pCid.push(pCid);
//2、当前拖拽节点的最新顺序，
for (let i = 0; i < siblings.length; i++) {
if (siblings[i].data.catId == draggingNode.data.catId) {
//如果遍历的是当前正在拖拽的节点
let catLevel = draggingNode.level;
if (siblings[i].level != draggingNode.level) {
//当前节点的层级发生变化
catLevel = siblings[i].level;
//修改他子节点的层级
this.updateChildNodeLevel(siblings[i]);
}
this.updateNodes.push({
catId: siblings[i].data.catId,
sort: i,
parentCid: pCid,
catLevel: catLevel
});
} else {
this.updateNodes.push({
catId: siblings[i].data.catId,
sort: i
});
}
}
//3、当前拖拽节点的最新层级
console.log("updateNodes", this.updateNodes);
},
2、服务端实现
@RequestMapping("/update/sort")
public R updateSort(@RequestBody List<CategoryEntity> categorys){
categoryService.updateBatchById(categorys);
return R.ok();
}
源码下载：
https://gitee.com/charlinchenlin/koo-erp
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