Android Studio配置与使用GSON框架解析json数据

Android Studio配置与使用Gson框架解析json数据

[toc]
这里使用一个联动的spinner来演示何如使用Gson解析json数据

一、配置gson环境

单击Open Module Settings

单击Dependencies，点击右边的绿色加号

选择选项的第一个Library Dependency

输入GSON关键字，点击搜索

这里选择一个合适的版本，然后点击OK

这时候gson框架就加载好了

二、安装GSON插件

注意插件安装完毕后请重启Android Studio

三、使用Gson插件生成Java Bean类

在src/main目录下（与java和res同级的目录下创建一个assets文件夹）
在此文件夹下复制一个地区编号的json文件
百度云下载地址：http://pan.baidu.com/s/1hrRAeCO

再创建一个bean包
包下创建一个名为AddrBean的类

在此类文件的任何位置右键

在弹出的对话框中将刚才下载文件的内容复制到这里

注意，这里自动生成的是中文的属性名，为了方便使用，我们将属性重命名

然后单击下一步，一个Bean类就创建出来了

package com.doservlet.bean;

import com.google.gson.annotations.SerializedName;

import java.util.List;

/**
 * Created by 陈小默
 * http://my.oschina.net/oschenxiaomo/blog
 * http://blog.csdn.net/qq_32583189
 */
public class AddrBean {

    @SerializedName("城市代码")
    private List provinceList;

    public List getProvinceList() {
        return provinceList;
    }

    public void setProvinceList(List provinceList) {
        this.provinceList = provinceList;
    }

    public static class ProvinceBean {
        @SerializedName("省")
        private String province;
        /**
         * 市名 : 北京
         * 编码 : 101010100
         */

        @SerializedName("市")
        private List cityList;

        public String getProvince() {
            return province;
        }

        public void setProvince(String province) {
            this.province = province;
        }

        public List getCityList() {
            return cityList;
        }

        public void setCityList(List cityList) {
            this.cityList = cityList;
        }

        public static class CityBean {
            @SerializedName("市名")
            private String cityName;
            @SerializedName("编码")
            private String cityCode;

            public String getCityName() {
                return cityName;
            }

            public void setCityName(String cityName) {
                this.cityName = cityName;
            }

            public String getCityCode() {
                return cityCode;
            }

            public void setCityCode(String cityCode) {
                this.cityCode = cityCode;
            }
        }
    }
}

四、创建一个布局文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.doservlet.activity.WeatherActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <Spinner
            android:id="@+id/province_list"
            android:layout_width="0dp"
            android:layout_height="40dp"
            android:layout_weight="1">Spinner>

        <Spinner
            android:id="@+id/city_list"
            android:layout_width="0dp"
            android:layout_height="40dp"
            android:layout_weight="1">Spinner>
    LinearLayout>
LinearLayout>

五、为spinner创建适配器

显示省份的适配器

package com.doservlet.adapter;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import com.doservlet.bean.AddrBean;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by 陈小默
 */
public class ProvinceAdapter extends BaseAdapter {

    private Context context;

    public ProvinceAdapter(Context context) {
        this.context = context;
    }

    private List provinceBeanList = new ArrayList<>();

    public void setProvinceBeanList(List provinceBeanList) {
        this.provinceBeanList = provinceBeanList;
        notifyDataSetChanged();
    }

    @Override
    public int getCount() {
        return provinceBeanList.size();
    }

    @Override
    public Object getItem(int position) {
        return provinceBeanList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        TextView tv = new TextView(context);
        tv.setText(provinceBeanList.get(position).getProvince());
        return tv;
    }
}

市的适配器

package com.doservlet.adapter;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import com.doservlet.bean.AddrBean;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by 陈小默 on 2016/5/20.
 */
public class CityAdapter extends BaseAdapter {
    private Context context;
    private List cityBeanList = new ArrayList<>();

    public void setCityBeanList(List cityBeanList) {
        this.cityBeanList = cityBeanList;
        notifyDataSetChanged();
    }

    public CityAdapter(Context context) {
        this.context = context;
    }

    @Override
    public int getCount() {
        return cityBeanList.size();
    }

    @Override
    public Object getItem(int position) {
        return cityBeanList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        TextView tv = new TextView(context);
        tv.setText(cityBeanList.get(position).getCityName());
        return tv;
    }
}

六、在Activity中解析数据

package com.doservlet.activity;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Spinner;

import com.doservlet.adapter.CityAdapter;
import com.doservlet.adapter.ProvinceAdapter;
import com.doservlet.bean.AddrBean;
import com.doservlet.bean.Weather;
import com.doservlet.xutilsdemo.R;
import com.google.gson.GsonBuilder;

import org.xutils.common.Callback;
import org.xutils.http.RequestParams;
import org.xutils.x;

import java.io.InputStream;
import java.io.InputStreamReader;

public class WeatherActivity extends AppCompatActivity {
    private Spinner spProvince, spCity;
    private AddrBean addrBean;
    private ProvinceAdapter adpProvince;
    private CityAdapter adpCity;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_weather);
        initView();
        loadData();
        register();
    }

    private void register() {
        spProvince.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView parent, View view, int position, long id) {
                adpCity.setCityBeanList(addrBean.getProvinceList().get(position).getCityList());
            }

            @Override
            public void onNothingSelected(AdapterView parent) {

            }
        });
    }

    private void loadData() {
        try {
            InputStream inputStream = getApplicationContext().getAssets().open("addr_china.json");

            addrBean = new GsonBuilder().create().fromJson(new InputStreamReader(inputStream), AddrBean.class);

            spProvince.setAdapter(adpProvince);
            adpProvince.setProvinceBeanList(addrBean.getProvinceList());

            spCity.setAdapter(adpCity);
            adpCity.setCityBeanList(addrBean.getProvinceList().get(0).getCityList());
        } catch (Throwable e) {
            e.printStackTrace();
        }
    }

    private void initView() {
        spCity = (Spinner) findViewById(R.id.city_list);
        spProvince = (Spinner) findViewById(R.id.province_list);

        adpProvince = new ProvinceAdapter(this);
        adpCity = new CityAdapter(this);
    }
}

好了现在运行就能看到联动的结果了