Android spinner三级连动菜单实现核心代码

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package com.l000phone.day05_spinnerexercise3;

import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;

import org.xmlpull.v1.XmlPullParser;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;

import com.l000phone.entity.Province;
import com.l000phone.util.CityWeatherParse;

public class MainActivity extends Activity {
private Spinner sp_province_id;// 省份信息显示下拉列表框控件
private Spinner sp_city_id;// 市级信息显示下拉列表框控件
private Spinner sp_county_id;// 县级信息显示下拉列表框控件

private ArrayAdapter<String> provinceAdapter;private ArrayAdapter<String> cityAdapter;private ArrayAdapter<String> countyAdapter;private String provinceName;// 选中的省份名private Set<String> address;@Overrideprotected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    // 思路：    // ①界面控件对象的获取    sp_province_id = (Spinner) findViewById(R.id.sp_province_id);    sp_city_id = (Spinner) findViewById(R.id.sp_city_id);    sp_county_id = (Spinner) findViewById(R.id.sp_county_id);    // ②准备数据源    XmlPullParser parser = getResources().getXml(R.xml.citys_weather);    List<Province> provinces = CityWeatherParse.getProvincesInfo(parser);    address = new LinkedHashSet<>();    // ③获得适配器对象    provinceAdapter = new ArrayAdapter<>(this,            android.R.layout.simple_spinner_dropdown_item,            CityWeatherParse.getAllProvinceNames(provinces));    cityAdapter = new ArrayAdapter<>(this,            android.R.layout.simple_spinner_dropdown_item);    countyAdapter = new ArrayAdapter<>(this,            android.R.layout.simple_spinner_dropdown_item);    // ④将适配器与Spinner控件进行绑定    sp_province_id.setAdapter(provinceAdapter);    sp_city_id.setAdapter(cityAdapter);    sp_county_id.setAdapter(countyAdapter);    // ⑤给Spinner下拉列表控件添加监听器（只需要给省份信息显示下拉列表框添加监听器即可）    OnItemSelectedListener listener = new MyOnItemSelectedListener(            provinces);    sp_province_id.setOnItemSelectedListener(listener);    sp_city_id.setOnItemSelectedListener(listener);    sp_county_id.setOnItemSelectedListener(listener);    sp_city_id.setSelection(0);}// 监听器OnItemSelectedListener实现类private final class MyOnItemSelectedListener implements        OnItemSelectedListener {    private List<Province> provinces;    public MyOnItemSelectedListener(List<Province> provinces) {        super();        this.provinces = provinces;    }    /*     * (non-Javadoc)     *      * @see     * android.widget.AdapterView.OnItemSelectedListener#onItemSelected(     * android.widget.AdapterView, android.view.View, int, long)     */    @Override    public void onItemSelected(AdapterView<?> parent, View view,            int position, long id) {        address.add(((TextView)view).getText().toString());        // 思路：        // ①根据选中的省份信息，将该省份对应的所有市级信息读取出来，设置到cityAdapter中        // ②根据选中的市级信息，将该市对应的所有县级信息读取出来，设置到countyAdapter中        String cityName;        switch (parent.getId()) {        case R.id.sp_province_id:            // -->修改市级适配器            // a）获取省份的名字            provinceName = ((TextView) view).getText().toString();            // b)将省份对应的所有市读取取出来            List<String> allCities = CityWeatherParse.getAllCityNames(// 在这儿用 就相当于 是 局部变量喽                    provinceName, provinces);            // c)修改适配器，并通知控件刷新            cityAdapter.clear();            cityAdapter.addAll(allCities);            cityAdapter.notifyDataSetChanged();            // 更新县级适配器操作            cityName = allCities.get(0);            modifyCountyAdapter(cityName);            MainActivity.this.setTitle("您的籍贯是："+address.toString());            break;        case R.id.sp_city_id:            // 获取市的名字            cityName = ((TextView) view).getText().toString();            Log.i("PROVINCE_NAME", provinceName);            // 更新县级适配器操作            modifyCountyAdapter(cityName);            MainActivity.this.setTitle("您的籍贯是："+address.toString());            break;        case R.id.sp_county_id:            MainActivity.this.setTitle("您的籍贯是："+address.toString());            address.clear();            break;        default:            break;        }    }    /**     * @param view     */    private void modifyCountyAdapter(String cityName) {        // b)将市对应的所有县读取取出来        List<String> allCounties = CityWeatherParse.getAllCountyames(                cityName, provinceName, provinces);        // c)修改适配器，并通知控件刷新        countyAdapter.clear();        countyAdapter.addAll(allCounties);        countyAdapter.notifyDataSetChanged();        sp_county_id.setSelection(0);    }    /*     * (non-Javadoc)     *      * @see     * android.widget.AdapterView.OnItemSelectedListener#onNothingSelected     * (android.widget.AdapterView)     */    @Override    public void onNothingSelected(AdapterView<?> parent) {    }}

}

“`util

/** *  */package com.l000phone.util;import java.io.FileNotFoundException;import java.io.IOException;import java.io.InputStream;import java.util.LinkedList;import java.util.List;import org.xmlpull.v1.XmlPullParser;import org.xmlpull.v1.XmlPullParserException;import android.util.Log;import com.l000phone.entity.City;import com.l000phone.entity.County;import com.l000phone.entity.Province;/** * Description： 城市天气情况解析<br/> * Copyright (c) , 2016, Jansonxu <br/> * This program is protected by copyright laws. <br/> * Program Name:CityWeatherParse.java <br/> * Date: 2016-2-17 *  * @author ly * @version : 1.0 */public class CityWeatherParse {    /**     * 获取所有省份的名字     *      * @param provinces     * @return     */    public static List<String> getAllProvinceNames(List<Province> provinces) {        List<String> allNames = new LinkedList<>();        for (Province Provice : provinces) {            allNames.add(Provice.getPn());        }        return allNames;    }    /**     *      * @param parser     * @return     */    public static List<Province> getProvincesInfo(XmlPullParser parser) {        // 思路        @SuppressWarnings("unused")        InputStream is = null;        List<Province> provinces = null;// 存放所有的省份信息        try {            // 解析            int eventType = parser.getEventType();            Province province = null;// 省份实例声明            City city = null;// 城市实例的声明            County county = null;// 县实例的声明            while (eventType != XmlPullParser.END_DOCUMENT) {                String nodeName = parser.getName();                switch (eventType) {                case XmlPullParser.START_DOCUMENT:                    System.out.println("xml解析开始...");                    provinces = new LinkedList<>();                    break;                case XmlPullParser.START_TAG:                    if ("p".equals(nodeName)) {                        province = new Province();// 省份实例的构建                        // 将p节点的属性设置到Province实例中                        setInstanceAttrValue(parser, province);                    } else if ("pn".equals(nodeName)) {                        province.setPn(parser.nextText());                    } else if ("c".equals(nodeName)) {                        city = new City();// 城市实例的构建                        // 将c节点的属性设置到City实例中                        setInstanceAttrValue(parser, city);                    } else if ("cn".equals(nodeName)) {                        city.setCn(parser.nextText());                    } else if ("d".equals(nodeName)) {                        county = new County();                        setInstanceAttrValue(parser, county);                        county.setDn(parser.nextText());                        // 应该将其添加到City中                        city.getCounties().add(county);                    }                    break;                case XmlPullParser.END_TAG:                    if ("c".equals(nodeName)) {                        province.getCities().add(city);                    } else if ("p".equals(nodeName)) {                        provinces.add(province);                    }                    break;                }                eventType = parser.next();            }            System.out.println("xml解析结束...");            // ④分析解析后的结果            System.out.println("xml文件解析的结果是：");            for (Province p : provinces) {                System.out.println(p);            }        } catch (XmlPullParserException e) {            e.printStackTrace();        } catch (FileNotFoundException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        } finally {            // ⑤释放资源            return provinces;        }    }    /**     * 设置实例的属性值     *      * @param parser     * @param obj     */    private static void setInstanceAttrValue(XmlPullParser parser, Object obj) {        for (int index = 0; index < parser.getAttributeCount(); index++) {            String attrName = parser.getAttributeName(index);            String attrValue = parser.getAttributeValue(index);            if ("p_id".equals(attrName)) {                ((Province) obj).setP_id(attrValue);            } else if ("c_id".equals(attrName)) {                ((City) obj).setC_id(attrValue);            } else if ("d_id".equals(attrName)) {                ((County) obj).setD_id(attrValue);            }        }    }    /**     * 根据传入的省份名，获取该省份下所有的市名     *      * @param provinceName     * @param provinces     * @return     */    public static List<String> getAllCityNames(String provinceName,            List<Province> provinces) {        List<String> cityNames = new LinkedList<>();        for (Province province : provinces) {            if (provinceName != null && provinceName.equals(province.getPn())) {                for (City city : province.getCities()) {                    cityNames.add(city.getCn());                }                break;            }        }        return cityNames;    }    /**     * 根据传入的省份名、城市名，获得该城市下所有的县名     *      * @param cityName     * @param provinceName     * @param provinces     * @return     */    public static List<String> getAllCountyames(String cityName,            String provinceName, List<Province> provinces) {        List<String> countyNames = new LinkedList<>();        EXIT_FLG: for (Province provice : provinces) {            if (provinceName != null && provinceName.equals(provice.getPn())) {                for (City city : provice.getCities()) {                    if (cityName != null && cityName.equals(city.getCn())) {                        for (County county : city.getCounties()) {                            countyNames.add(county.getDn());                        }                        break EXIT_FLG;                    }                }            }        }        Log.i("PROVINCE_NAME", "countyNames = " + countyNames + ",cityName = "                + cityName + ",provinces=" + provinces);        return countyNames;    }}

entity

/** *  */package com.l000phone.entity;import java.util.LinkedList;import java.util.List;/** * Description： 地级市实体类<br/> * Copyright (c) , 2016, Jansonxu <br/> * This program is protected by copyright laws. <br/> * Program Name:City.java <br/> * Date: 2016-2-17 *  * @authorly * @version : 1.0 */public class City {    private String c_id;// 城市的id    private String cn;// 城市名字    private List<County> counties = new LinkedList<>();// 多个县，县级市    public City() {        super();    }    public City(String c_id, String cn, List<County> counties) {        super();        this.c_id = c_id;        this.cn = cn;        this.counties = counties;    }    public String getC_id() {        return c_id;    }    public void setC_id(String c_id) {        this.c_id = c_id;    }    public String getCn() {        return cn;    }    public void setCn(String cn) {        this.cn = cn;    }    public List<County> getCounties() {        return counties;    }    public void setCounties(List<County> counties) {        this.counties = counties;    }    @Override    public String toString() {        return "City [c_id=" + c_id + ", cn=" + cn + ", counties=" + counties                + "]";    }}

/**
*
*/
package com.l000phone.entity;

/**
* Description： 县（县级市）实体类

* Copyright (c) , 2016, Jansonxu

* This program is protected by copyright laws.

* Program Name:County.java

* Date: 2016-2-17
*
* @author ly
* @version : 1.0
*/
public class County {
private String d_id;// 县的id
private String dn;// 县名

public County() {    super();}public County(String d_id, String dn) {    super();    this.d_id = d_id;    this.dn = dn;}public String getD_id() {    return d_id;}public void setD_id(String d_id) {    this.d_id = d_id;}public String getDn() {    return dn;}public void setDn(String dn) {    this.dn = dn;}@Overridepublic String toString() {    return "County [d_id=" + d_id + ", dn=" + dn + "]";}

}

/**
*
*/
package com.l000phone.entity;

import java.util.LinkedList;
import java.util.List;

/**
* Description： 省份实体类

* Copyright (c) , 2016, Jansonxu

* This program is protected by copyright laws.

* Program Name:Province.java

* Date: 2016-2-17
*
* @author ly
* @version : 1.0
*/
public class Province {
private String p_id;// 省份id
private String pn;// 省份名字
private List cities = new LinkedList<>();// 多个地级市

public Province() {    super();}public Province(String p_id, String pn, List<City> cities) {    super();    this.p_id = p_id;    this.pn = pn;    this.cities = cities;}public String getP_id() {    return p_id;}public void setP_id(String p_id) {    this.p_id = p_id;}public String getPn() {    return pn;}public void setPn(String pn) {    this.pn = pn;}public List<City> getCities() {    return cities;}public void setCities(List<City> cities) {    this.cities = cities;}@Overridepublic String toString() {    return "Province [p_id=" + p_id + ", pn=" + pn + ", cities=" + cities            + "]";}

}

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