Android使用Kotlin利用Gson解析多层嵌套Json数据

1、依赖

build.gradle(app)中加入

dependencies {
implementation 'com.google.code.gson:gson:2.8.9'
}

2、解析

1. 假设这是要解析Json数据

var responseStr =
"{"code": 200,"message": "操作成功","data": {"pageNum": 1,"pageSize": 5,"totalPage": 2,"total": 8,"list": [{"id": 1,"username": "test","password": "123","icon": "https://macro-oss.oss-cn-shenzhen.aliyuncs.com/mall/icon/github_icon_02.png","email": "[e-mail]","nickName": "测试账号","note": null,"createTime": "2018-09-29T05:55:30.000+00:00","loginTime": "2018-09-29T05:55:39.000+00:00","status": 1}, {"id": 3,"username": "admin","password": "123","icon": "https://macro-oss.oss-cn-shenzhen.aliyuncs.com/mall/icon/github_icon_01.png","email": "[e-mail]","nickName": "系统管理员","note": "系统管理员","createTime": "2018-10-08T05:32:47.000+00:00","loginTime": "2019-04-20T04:45:16.000+00:00","status": 1}, {"id": 4,"username": "macro","password": "123","icon": "https://macro-oss.oss-cn-shenzhen.aliyuncs.com/mall/icon/github_icon_01.png","email": "[e-mail]","nickName": "macro","note": "macro专用","createTime": "2019-10-06T07:53:51.000+00:00","loginTime": "2020-02-03T06:55:55.000+00:00","status": 1}, {"id": 6,"username": "productAdmin","password": "123","icon": "https://macro-oss.oss-cn-shenzhen.aliyuncs.com/mall/icon/github_icon_03.png","email": "[e-mail]","nickName": "商品管理员","note": "只有商品权限","createTime": "2020-02-07T08:15:08.000+00:00","loginTime": null,"status": 1}, {"id": 7,"username": "orderAdmin","password": "123","icon": "https://macro-oss.oss-cn-shenzhen.aliyuncs.com/mall/icon/github_icon_04.png","email": "[e-mail]","nickName": "订单管理员","note": "只有订单管理权限","createTime": "2020-02-07T08:15:50.000+00:00","loginTime": null,"status": 1}]}
}     

2. 分析Json的结构

• Json主要构成部分
  
  对应的类

data class Result(val code: Int,val message: String,val data: Data
) : Serializable

• data部分的组成
  
  对应的类：

data class Data(val pageNum: Int,val pageSize: Int,val totalPage: Int,val total: Int,val list: List<list> = ArrayList(),
) : Serializable

Json中list使用[ ]，所以这里的list写成： val list: List<list> = ArrayList()

• list部分的组成
  
  对应的类：

data class list(val id: Int,val username: String,val password: String,val icon: String,val email: String,val nickName: String,val createTime: String,val loginTime: String,val status: Int
) : Serializable

重点提醒：类里面的属性名必须跟Json字段里面的Key是一模一样的，否则会导致解析不成功
如果不一致：

这个部分我刚开始处理也错了，找了好久才发现，一定要注意

3. 开始解析

		val gson = Gson()val resultType = object :  TypeToken<Result>() {}.typeval fromJson = gson.fromJson<Result>(responseStr, resultType)

4. 提取数据
   通过fromJson提取
   如：