Android使用android-wheel实现省市县三级联动

{"citylist": [{"p":"河北",  "c":[{"n":"石家庄",  "a":[{"s":"长安区"},{"s":"桥东区"}，{"s":"鹿泉市"}] }]}

<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:background="#000000"  android:orientation="vertical" >  <TextView    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_gravity="center"    android:layout_margin="10dp"    android:text="请选择城市"    android:textColor="#ffffff"    android:textSize="20sp" />  <LinearLayout    android:layout_width="fill_parent"    android:layout_height="wrap_content"    android:background="@drawable/layout_bg"    android:orientation="horizontal" >    <kankan.wheel.widget.WheelView      android:id="@+id/id_province"      android:layout_width="0dp"      android:layout_height="wrap_content"      android:layout_weight="1" >    </kankan.wheel.widget.WheelView>    <kankan.wheel.widget.WheelView      android:id="@+id/id_city"      android:layout_width="0dp"      android:layout_height="wrap_content"      android:layout_weight="1" >    </kankan.wheel.widget.WheelView>    <kankan.wheel.widget.WheelView      android:id="@+id/id_area"      android:layout_width="0dp"      android:layout_height="wrap_content"      android:layout_weight="1" >    </kankan.wheel.widget.WheelView>  </LinearLayout>    <Button  android:onClick="showChoose" android:layout_gravity="right" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="确定"    />  </LinearLayout>

package com.example.wheel_province;import java.io.IOException;import java.io.InputStream;import java.util.HashMap;import java.util.Map;import kankan.wheel.widget.OnWheelChangedListener;import kankan.wheel.widget.WheelView;import kankan.wheel.widget.adapters.ArrayWheelAdapter;import org.json.JSONArray;import org.json.JSONException;import org.json.JSONObject;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.widget.Toast;/** *  * @author zhy *  */public class CitiesActivity extends Activity implements OnWheelChangedListener{ /** * 把全国的省市区的信息以json的格式保存，解析完成后赋值为null */ private JSONObject mJsonObj; /** * 省的WheelView控件 */ private WheelView mProvince; /** * 市的WheelView控件 */ private WheelView mCity; /** * 区的WheelView控件 */ private WheelView mArea; /** * 所有省 */ private String[] mProvinceDatas; /** * key - 省 value - 市s */ private Map<String, String[]> mCitisDatasMap = new HashMap<String, String[]>(); /** * key - 市 values - 区s */ private Map<String, String[]> mAreaDatasMap = new HashMap<String, String[]>(); /** * 当前省的名称 */ private String mCurrentProviceName; /** * 当前市的名称 */ private String mCurrentCityName; /** * 当前区的名称 */ private String mCurrentAreaName =""; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.citys); initJsonData(); mProvince = (WheelView) findViewById(R.id.id_province); mCity = (WheelView) findViewById(R.id.id_city); mArea = (WheelView) findViewById(R.id.id_area); initDatas(); mProvince.setViewAdapter(new ArrayWheelAdapter<String>(this, mProvinceDatas)); // 添加change事件 mProvince.addChangingListener(this); // 添加change事件 mCity.addChangingListener(this); // 添加change事件 mArea.addChangingListener(this); mProvince.setVisibleItems(5); mCity.setVisibleItems(5); mArea.setVisibleItems(5); updateCities(); updateAreas(); } /** * 根据当前的市，更新区WheelView的信息 */ private void updateAreas() { int pCurrent = mCity.getCurrentItem(); mCurrentCityName = mCitisDatasMap.get(mCurrentProviceName)[pCurrent]; String[] areas = mAreaDatasMap.get(mCurrentCityName); if (areas == null) {  areas = new String[] { "" }; } mArea.setViewAdapter(new ArrayWheelAdapter<String>(this, areas)); mArea.setCurrentItem(0); } /** * 根据当前的省，更新市WheelView的信息 */ private void updateCities() { int pCurrent = mProvince.getCurrentItem(); mCurrentProviceName = mProvinceDatas[pCurrent]; String[] cities = mCitisDatasMap.get(mCurrentProviceName); if (cities == null) {  cities = new String[] { "" }; } mCity.setViewAdapter(new ArrayWheelAdapter<String>(this, cities)); mCity.setCurrentItem(0); updateAreas(); } /** * 解析整个Json对象，完成后释放Json对象的内存 */ private void initDatas() { try {  JSONArray jsonArray = mJsonObj.getJSONArray("citylist");  mProvinceDatas = new String[jsonArray.length()];  for (int i = 0; i < jsonArray.length(); i++)  {  JSONObject jsonP = jsonArray.getJSONObject(i);// 每个省的json对象  String province = jsonP.getString("p");// 省名字  mProvinceDatas[i] = province;  JSONArray jsonCs = null;  try  {   /**   * Throws JSONException if the mapping doesn't exist or is   * not a JSONArray.   */   jsonCs = jsonP.getJSONArray("c");  } catch (Exception e1)  {   continue;  }  String[] mCitiesDatas = new String[jsonCs.length()];  for (int j = 0; j < jsonCs.length(); j++)  {   JSONObject jsonCity = jsonCs.getJSONObject(j);   String city = jsonCity.getString("n");// 市名字   mCitiesDatas[j] = city;   JSONArray jsonAreas = null;   try   {   /**    * Throws JSONException if the mapping doesn't exist or    * is not a JSONArray.    */   jsonAreas = jsonCity.getJSONArray("a");   } catch (Exception e)   {   continue;   }   String[] mAreasDatas = new String[jsonAreas.length()];// 当前市的所有区   for (int k = 0; k < jsonAreas.length(); k++)   {   String area = jsonAreas.getJSONObject(k).getString("s");// 区域的名称   mAreasDatas[k] = area;   }   mAreaDatasMap.put(city, mAreasDatas);  }  mCitisDatasMap.put(province, mCitiesDatas);  } } catch (JSONException e) {  e.printStackTrace(); } mJsonObj = null; } /** * 从assert文件夹中读取省市区的json文件，然后转化为json对象 */ private void initJsonData() { try {  StringBuffer sb = new StringBuffer();  InputStream is = getAssets().open("city.json");  int len = -1;  byte[] buf = new byte[1024];  while ((len = is.read(buf)) != -1)  {  sb.append(new String(buf, 0, len, "gbk"));  }  is.close();  mJsonObj = new JSONObject(sb.toString()); } catch (IOException e) {  e.printStackTrace(); } catch (JSONException e) {  e.printStackTrace(); } } /** * change事件的处理 */ @Override public void onChanged(WheelView wheel, int oldValue, int newValue) { if (wheel == mProvince) {  updateCities(); } else if (wheel == mCity) {  updateAreas(); } else if (wheel == mArea) {  mCurrentAreaName = mAreaDatasMap.get(mCurrentCityName)[newValue]; } } public void showChoose(View view) { Toast.makeText(this, mCurrentProviceName + mCurrentCityName + mCurrentAreaName, 1).show(); }}