仿美團實現城市定位。

因爲項目需要用到這個城市定位，看到美團的感覺不錯，就拿過來用了。先來看一下項目結構。

這是我們項目的效果

Activity01.java 這個類是我們主要的操作邏輯實現類

package com.droid;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.regex.Pattern;

import android.app.Activity;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.PixelFormat;
import android.os.Bundle;
import android.os.Handler;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.view.WindowManager;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.EditText;
import android.widget.GridView;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import com.baidu.location.BDLocation;
import com.baidu.location.BDLocationListener;
import com.baidu.location.LocationClient;
import com.baidu.location.LocationClientOption;
import com.droid.MyLetterListView.OnTouchingLetterChangedListener;

public class Activity01 extends Activity implements OnScrollListener {
private BaseAdapter adapter;
private ResultListAdapter resultListAdapter;
private ListView personList;
private ListView resultList;//搜索結果列表
private TextView overlay; // 對話框首字母textview
private MyLetterListView letterListView; // A-Z listview
private HashMap<String, Integer> alphaIndexer;// 存放存在的漢語拼音首字母和與之對應的列表位置
private String[] sections;// 存放存在的漢語拼音首字母
private Handler handler;
private OverlayThread overlayThread; // 顯示首字母對話框
private ArrayList<City> allCity_lists; // 所有城市列表
private ArrayList<City> city_lists;// 城市列表
private ArrayList<City> city_hot;//熱門城市列表
private ArrayList<City> city_result;//城市結果
private ArrayList<String> city_history;//歷史城市結果
private EditText sh; //搜索框
private TextView tv_noresult; //顯示搜索結果
//定位
private LocationClient mLocationClient;
private MyLocationListener mMyLocationListener;
public TextView city;
private String currentCity; // 用於保存定位到的城市
private int locateProcess = 1; // 記錄當前定位的狀態正在定位（1）-定位成功（2）-定位失敗（3）
//是否需要新的
private boolean isNeedFresh;
//我們從文件的全國城市列表
private DatabaseHelper helper;

@Override
public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  personList = (ListView) findViewById(R.id.list_view);
  allCity_lists = new ArrayList<City>();
  city_hot = new ArrayList<City>();
  city_result = new ArrayList<City>();
  city_history = new ArrayList<String>();
  resultList = (ListView) findViewById(R.id.search_result);
  sh = (EditText) findViewById(R.id.sh);
  //沒有該城市的搜索結果出現該提示消息
  tv_noresult = (TextView) findViewById(R.id.tv_noresult);
  helper = new DatabaseHelper(this);
  //城市搜索框增加監聽器
  sh.addTextChangedListener(new TextWatcher() {

   @Override
   //文本改變前調用的方法
   //這個方法被調用，說明在s字符串中，從start位置開始的count個字符即將被長度爲after的新文本所取代。在這個方法裏面改變s，會報錯。
   public void onTextChanged(CharSequence s, int start, int before,
     int count) {
    if (s.toString() == null || "".equals(s.toString())) {
     //View缺省（默認）爲可見的，在應用可以通過setVisibility 修改View的可見性，View可用性可以有如下三種狀態：
     //View.VISIBLE View可見
     //View.INVISIBLE View不可以見，但仍然佔據可見時的大小和位置。
     //View.GONE View不可見，且不佔據空間
     letterListView.setVisibility(View.VISIBLE);
     personList.setVisibility(View.VISIBLE);
     resultList.setVisibility(View.GONE);
     tv_noresult.setVisibility(View.GONE);
    } else {
     //保證下一次進來搜索頁面，不會保留上一次的搜索結果
     city_result.clear();
     letterListView.setVisibility(View.GONE);
     personList.setVisibility(View.GONE);
     getResultCityList(s.toString());
     if (city_result.size() <= 0) {
      tv_noresult.setVisibility(View.VISIBLE);
      resultList.setVisibility(View.GONE);
     } else {
      tv_noresult.setVisibility(View.GONE);
      resultList.setVisibility(View.VISIBLE);
      resultListAdapter.notifyDataSetChanged();
     }
    }
   }

   @Override
   //文本調用時的方法
   // //這個方法被調用，說明在s字符串中，從start位置開始的count個字符剛剛取代了長度爲before的舊文本。在這個方法裏面改變
   public void beforeTextChanged(CharSequence s, int start, int count,
     int after) {
   }

   @Override
  //方放調用完成後的方法
   //這個方法被調用，那麼說明s字符串的某個地方已經被改變。

public void afterTextChanged(Editable s) {

   }
  });
  letterListView = (MyLetterListView) findViewById(R.id.MyLetterListView01);
  letterListView
    .setOnTouchingLetterChangedListener(new LetterListViewListener());
//字母表的角標，t
  alphaIndexer = new HashMap<String, Integer>();
  handler = new Handler();
  overlayThread = new OverlayThread();
  isNeedFresh = true;
  //城市列表的item點擊事件
  personList.setOnItemClickListener(new OnItemClickListener() {

   @Override
   public void onItemClick(AdapterView<?> parent, View view,
     int position, long id) {
    if (position >= 4) {

     Toast.makeText(getApplicationContext(),
       allCity_lists.get(position).getName(),
       Toast.LENGTH_SHORT).show();
    }
   }
  });
  locateProcess = 1;
  personList.setAdapter(adapter);
  personList.setOnScrollListener(this);
  resultListAdapter = new ResultListAdapter(this, city_result);
  resultList.setAdapter(resultListAdapter);
  resultList.setOnItemClickListener(new OnItemClickListener() {

   @Override
   public void onItemClick(AdapterView<?> parent, View view,
     int position, long id) {
    Toast.makeText(getApplicationContext(),
      city_result.get(position).getName(), Toast.LENGTH_SHORT)
      .show();
   }
  });
  //首字母索引的方法
  initOverlay();
  //初始化城市
  cityInit();
  //初始化熱門城市
  hotCityInit();
  //初始化曾經搜索過的城市
  hisCityInit();
  setAdapter(allCity_lists, city_hot, city_history);

  mLocationClient = new LocationClient(this.getApplicationContext());
  mMyLocationListener = new MyLocationListener();
  mLocationClient.registerLocationListener(mMyLocationListener);
  //對定位進行初始化
  InitLocation();
  //開始定位
  mLocationClient.start();
}
   //對城市信息進行插入操作
public void InsertCity(String name) {
  SQLiteDatabase db = helper.getReadableDatabase();
  Cursor cursor = db.rawQuery("select * from recentcity where name = '"
    + name + "'", null);
  if (cursor.getCount() > 0) { //
   db.delete("recentcity", "name = ?", new String[] { name });
  }
  db.execSQL("insert into recentcity(name, date) values('" + name + "', "
    + System.currentTimeMillis() + ")");
  db.close();
}

private void InitLocation() {
  // 設置定位參數
  LocationClientOption option = new LocationClientOption();
  option.setCoorType("bd09ll"); // 設置座標類型
  option.setScanSpan(10000); // 10分鐘掃描1次
  // 需要地址信息，設置爲其他任何值（string類型，且不能爲null）時，都表示無地址信息。
  option.setAddrType("all");
  // 設置是否返回POI的電話和地址等詳細信息。默認值爲false，即不返回POI的電話和地址信息。
  option.setPoiExtraInfo(true);
  // 設置產品線名稱。強烈建議您使用自定義的產品線名稱，方便我們以後爲您提供更高效準確的定位服務。
  option.setProdName("通過GPS定位我當前的位置");
  // 禁用啓用緩存定位數據
  option.disableCache(true);
  // 設置最多可返回的POI個數，默認值爲3。由於POI查詢比較耗費流量，設置最多返回的POI個數，以便節省流量。
  option.setPoiNumber(3);
  // 設置定位方式的優先級。
  // 當gps可用，而且獲取了定位結果時，不再發起網絡請求，直接返回給用戶座標。這個選項適合希望得到準確座標位置的用戶。如果gps不可用，再發起網絡請求，進行定位。
  option.setPriority(LocationClientOption.GpsFirst);
  mLocationClient.setLocOption(option);
}
//城市信息的初始化處
private void cityInit() {
  City city = new City("定位", "0"); // 當前定位城市
  allCity_lists.add(city);
  city = new City("最近", "1"); // 最近訪問的城市
  allCity_lists.add(city);
  city = new City("熱門", "2"); // 熱門城市
  allCity_lists.add(city);
  city = new City("全部", "3"); // 全部城市
  allCity_lists.add(city);
  city_lists = getCityList();
  allCity_lists.addAll(city_lists);
}

/**
* 熱門城市
*/
//city方法中參數的"2"應該是設置在拼音檢索中的優先級
//可以在這方法中自己添加熱門城市的信息
public void hotCityInit() {
  City city = new City("上海", "2");
  city_hot.add(city);
  city = new City("北京", "2");
  city_hot.add(city);
  city = new City("廣州", "2");
  city_hot.add(city);
  city = new City("深圳", "2");
  city_hot.add(city);
  city = new City("武漢", "2");
  city_hot.add(city);
  city = new City("天津", "2");
  city_hot.add(city);
  city = new City("西安", "2");
  city_hot.add(city);
  city = new City("南京", "2");
  city_hot.add(city);
  city = new City("杭州", "2");
  city_hot.add(city);
  city = new City("成都", "2");
  city_hot.add(city);
  city = new City("重慶", "2");
  city_hot.add(city);
  city = new City("吉安", "2");
  city_hot.add(city);

}

private void hisCityInit() {
  SQLiteDatabase db = helper.getReadableDatabase();
  Cursor cursor = db.rawQuery(
    "select * from recentcity order by date desc limit 0, 3", null);
  while (cursor.moveToNext()) {
   city_history.add(cursor.getString(1));
  }
  cursor.close();
  db.close();
}

@SuppressWarnings("unchecked")
private ArrayList<City> getCityList() {
  DBHelper dbHelper = new DBHelper(this);
  ArrayList<City> list = new ArrayList<City>();
  try {
   dbHelper.createDataBase();
   SQLiteDatabase db = dbHelper.getWritableDatabase();
   Cursor cursor = db.rawQuery("select * from city", null);
   City city;
   while (cursor.moveToNext()) {
    city = new City(cursor.getString(1), cursor.getString(2));
    list.add(city);
   }
   cursor.close();
   db.close();
  } catch (IOException e) {
   e.printStackTrace();
  }
  Collections.sort(list, comparator);
  return list;
}

@SuppressWarnings("unchecked")
private void getResultCityList(String keyword) {
  DBHelper dbHelper = new DBHelper(this);
  try {
   dbHelper.createDataBase();
   SQLiteDatabase db = dbHelper.getWritableDatabase();
   Cursor cursor = db.rawQuery(
     "select * from city where name like \"%" + keyword
       + "%\" or pinyin like \"%" + keyword + "%\"", null);
   City city;
   Log.e("info", "length = " + cursor.getCount());
   while (cursor.moveToNext()) {
    city = new City(cursor.getString(1), cursor.getString(2));
    city_result.add(city);
   }
   cursor.close();
   db.close();
  } catch (IOException e) {
   e.printStackTrace();
  }
  Collections.sort(city_result, comparator);
}

/**
* a-z排序
*/
@SuppressWarnings("rawtypes")
Comparator comparator = new Comparator<City>() {
  @Override
  public int compare(City lhs, City rhs) {
   String a = lhs.getPinyi().substring(0, 1);
   String b = rhs.getPinyi().substring(0, 1);
   int flag = a.compareTo(b);
   if (flag == 0) {
    return a.compareTo(b);
   } else {
    return flag;
   }
  }
};

private void setAdapter(List<City> list, List<City> hotList,
   List<String> hisCity) {
  adapter = new ListAdapter(this, list, hotList, hisCity);
  personList.setAdapter(adapter);
}

/**
* 實現實位回調監聽
*/
public class MyLocationListener implements BDLocationListener {

  @Override
  public void onReceiveLocation(BDLocation arg0) {
   Log.e("info", "city = " + arg0.getCity());
   if (!isNeedFresh) {
    return;
   }
   isNeedFresh = false;
   if (arg0.getCity() == null) {
    locateProcess = 3; // 定位失敗
    personList.setAdapter(adapter);
    adapter.notifyDataSetChanged();
    return;
   }
   currentCity = arg0.getCity().substring(0,
     arg0.getCity().length() - 1);
   locateProcess = 2; // 定位成功
   personList.setAdapter(adapter);
   adapter.notifyDataSetChanged();
  }

@Override
public void onReceivePoi(BDLocation arg0) {

}
}

private class ResultListAdapter extends BaseAdapter {
private LayoutInflater inflater;
private ArrayList<City> results = new ArrayList<City>();

  public ResultListAdapter(Context context, ArrayList<City> results) {
   inflater = LayoutInflater.from(context);
   this.results = results;
  }

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

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

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

  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
   ViewHolder viewHolder = null;
   if (convertView == null) {
    convertView = inflater.inflate(R.layout.list_item, null);
    viewHolder = new ViewHolder();
    viewHolder.name = (TextView) convertView
      .findViewById(R.id.name);
    convertView.setTag(viewHolder);
   } else {
    viewHolder = (ViewHolder) convertView.getTag();
   }
   viewHolder.name.setText(results.get(position).getName());
   return convertView;
  }

  class ViewHolder {
   TextView name;
  }
}

public class ListAdapter extends BaseAdapter {
  private Context context;
  private LayoutInflater inflater;
  private List<City> list;
  private List<City> hotList;
  private List<String> hisCity;
  final int VIEW_TYPE = 5;

  public ListAdapter(Context context, List<City> list,
    List<City> hotList, List<String> hisCity) {
   this.inflater = LayoutInflater.from(context);
   this.list = list;
   this.context = context;
   this.hotList = hotList;
   this.hisCity = hisCity;
   alphaIndexer = new HashMap<String, Integer>();
   sections = new String[list.size()];
   for (int i = 0; i < list.size(); i++) {
    // 當前漢語拼音首字母
    String currentStr = getAlpha(list.get(i).getPinyi());
    // 上一個漢語拼音首字母，如果不存在爲" "
    String previewStr = (i - 1) >= 0 ? getAlpha(list.get(i - 1)
      .getPinyi()) : " ";
    if (!previewStr.equals(currentStr)) {
     String name = getAlpha(list.get(i).getPinyi());
     alphaIndexer.put(name, i);
     sections[i] = name;
    }
   }
  }

  @Override
  public int getViewTypeCount() {
   return VIEW_TYPE;
  }

  @Override
  public int getItemViewType(int position) {
   return position < 4 ? position : 4;
  }

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

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

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

ViewHolder holder;

  @Override
  public View getView(int position, View convertView, ViewGroup parent) {

   int viewType = getItemViewType(position);
   if (viewType == 0) { // 定位
    convertView = inflater.inflate(R.layout.frist_list_item, null);
    //定位的信息/提示
    TextView locateHint = (TextView) convertView
      .findViewById(R.id.locateHint);
    //定位城市的信息，例如你在廣州，這個textView顯示的就是廣州
    city = (TextView) convertView.findViewById(R.id.lng_city);
    city.setOnClickListener(new OnClickListener() {
     @Override
     public void onClick(View v) {
      //如果定位成功的話
      if (locateProcess == 2) {

       Toast.makeText(getApplicationContext(),
         city.getText().toString(),
         Toast.LENGTH_SHORT).show();
      }
      //如果定位失敗的話，我們把定位狀態在切換到正在定位
      //一般我們出現的定位失敗的情況都是未開啓網絡或者wifl或者gps
      else if (locateProcess == 3) {
       locateProcess = 1;
       personList.setAdapter(adapter);
       //刷新我們列表
       adapter.notifyDataSetChanged();
       mLocationClient.stop();
       //刷新爲新的
       isNeedFresh = true;
       InitLocation();
       //當我們的定位城市信息列表爲空的時候，我們繼續開啓定位
       currentCity = "";
       mLocationClient.start();
      }
     }
    });
    //我們定位中等待的icon圖標
    ProgressBar pbLocate = (ProgressBar) convertView
      .findViewById(R.id.pbLocate);
    if (locateProcess == 1) { // 正在定位
     locateHint.setText("正在定位");
     city.setVisibility(View.GONE);
     pbLocate.setVisibility(View.VISIBLE);
    } else if (locateProcess == 2) { // 定位成功
     locateHint.setText("當前定位城市");
     city.setVisibility(View.VISIBLE);
     city.setText(currentCity);
     mLocationClient.stop();
     pbLocate.setVisibility(View.GONE);
    } else if (locateProcess == 3) {
     locateHint.setText("未定位到城市,請選擇");
     city.setVisibility(View.VISIBLE);
     city.setText("重新選擇");
     pbLocate.setVisibility(View.GONE);
    }
   } else if (viewType == 1) { // 最近訪問城市
    convertView = inflater.inflate(R.layout.recent_city, null);
    GridView rencentCity = (GridView) convertView
      .findViewById(R.id.recent_city);
    rencentCity
      .setAdapter(new HitCityAdapter(context, this.hisCity));
    rencentCity.setOnItemClickListener(new OnItemClickListener() {

     @Override
     public void onItemClick(AdapterView<?> parent, View view,
       int position, long id) {

      Toast.makeText(getApplicationContext(),
        city_history.get(position), Toast.LENGTH_SHORT)
        .show();

     }
    });
    TextView recentHint = (TextView) convertView
      .findViewById(R.id.recentHint);
    recentHint.setText("最近訪問的城市");
   } else if (viewType == 2) {
    convertView = inflater.inflate(R.layout.recent_city, null);
    GridView hotCity = (GridView) convertView
      .findViewById(R.id.recent_city);
    hotCity.setOnItemClickListener(new OnItemClickListener() {

     @Override
     public void onItemClick(AdapterView<?> parent, View view,
       int position, long id) {

      Toast.makeText(getApplicationContext(),
        city_hot.get(position).getName(),
        Toast.LENGTH_SHORT).show();

     }
    });
    hotCity.setAdapter(new HotCityAdapter(context, this.hotList));
    TextView hotHint = (TextView) convertView
      .findViewById(R.id.recentHint);
    hotHint.setText("熱門城市");
   } else if (viewType == 3) {
    convertView = inflater.inflate(R.layout.total_item, null);
   } else {
    if (convertView == null) {
     convertView = inflater.inflate(R.layout.list_item, null);
     holder = new ViewHolder();
     holder.alpha = (TextView) convertView
       .findViewById(R.id.alpha);
     holder.name = (TextView) convertView
       .findViewById(R.id.name);
     convertView.setTag(holder);
    } else {
     holder = (ViewHolder) convertView.getTag();
    }
    if (position >= 1) {
     holder.name.setText(list.get(position).getName());
     String currentStr = getAlpha(list.get(position).getPinyi());
     String previewStr = (position - 1) >= 0 ? getAlpha(list
       .get(position - 1).getPinyi()) : " ";
     if (!previewStr.equals(currentStr)) {
      holder.alpha.setVisibility(View.VISIBLE);
      //這裏是設置首字母的比如重慶 C首字母
      holder.alpha.setText(currentStr);
     } else {
      holder.alpha.setVisibility(View.GONE);
     }
    }
   }
   return convertView;
  }

  private class ViewHolder {
   TextView alpha; // 首字母標題
   TextView name; // 城市名字
  }
}

@Override
//封裝着定位停止的方法
protected void onStop() {
mLocationClient.stop();
super.onStop();
}

class HotCityAdapter extends BaseAdapter {
  private Context context;
  private LayoutInflater inflater;
  private List<City> hotCitys;

  public HotCityAdapter(Context context, List<City> hotCitys) {
   this.context = context;
   inflater = LayoutInflater.from(this.context);
   this.hotCitys = hotCitys;
  }

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

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

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

  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
   convertView = inflater.inflate(R.layout.item_city, null);
   TextView city = (TextView) convertView.findViewById(R.id.city);
   city.setText(hotCitys.get(position).getName());
   return convertView;
  }
}

class HitCityAdapter extends BaseAdapter {
  private Context context;
  private LayoutInflater inflater;
  private List<String> hotCitys;

  public HitCityAdapter(Context context, List<String> hotCitys) {
   this.context = context;
   inflater = LayoutInflater.from(this.context);
   this.hotCitys = hotCitys;
  }

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

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

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

private boolean mReady;

// 初始化漢語拼音首字母彈出提示框
private void initOverlay() {
  mReady = true;
  LayoutInflater inflater = LayoutInflater.from(this);
  overlay = (TextView) inflater.inflate(R.layout.overlay, null);
  overlay.setVisibility(View.INVISIBLE);
  WindowManager.LayoutParams lp = new WindowManager.LayoutParams(
    LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT,
    WindowManager.LayoutParams.TYPE_APPLICATION,
    WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
      | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE,
    PixelFormat.TRANSLUCENT);
  WindowManager windowManager = (WindowManager) this
    .getSystemService(Context.WINDOW_SERVICE);
  windowManager.addView(overlay, lp);
}

private boolean isScroll = false;

private class LetterListViewListener implements
OnTouchingLetterChangedListener {

  @Override
  //overlay覆蓋物
  public void onTouchingLetterChanged(final String s) {
   isScroll = false;
   if (alphaIndexer.get(s) != null) {
    int position = alphaIndexer.get(s);
    personList.setSelection(position);
    overlay.setText(s);
    overlay.setVisibility(View.VISIBLE);
    handler.removeCallbacks(overlayThread);
    // 延遲一秒後執行，讓overlay爲不可見
    handler.postDelayed(overlayThread, 1000);
   }
  }
}

// 設置overlay不可見
private class OverlayThread implements Runnable {
  @Override
  public void run() {
   overlay.setVisibility(View.GONE);
  }
}

// 獲得漢語拼音首字母
private String getAlpha(String str) {
  if (str == null) {
   return "#";
  }
  if (str.trim().length() == 0) {
   return "#";
  }
  char c = str.trim().substring(0, 1).charAt(0);
  // 正則表達式，判斷首字母是否是英文字母
  Pattern pattern = Pattern.compile("^[A-Za-z]+$");
  if (pattern.matcher(c + "").matches()) {
   return (c + "").toUpperCase();
  } else if (str.equals("0")) {
   return "定位";
  } else if (str.equals("1")) {
   return "最近";
  } else if (str.equals("2")) {
   return "熱門";
  } else if (str.equals("3")) {
   return "全部";
  } else {
   return "#";
  }
}

@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
  if (scrollState == SCROLL_STATE_TOUCH_SCROLL
    || scrollState == SCROLL_STATE_FLING) {
   isScroll = true;
  }
}

@Override
public void onScroll(AbsListView view, int firstVisibleItem,
   int visibleItemCount, int totalItemCount) {
  if (!isScroll) {
   return;
  }

  if (mReady) {
   String text;
   String name = allCity_lists.get(firstVisibleItem).getName();
   String pinyin = allCity_lists.get(firstVisibleItem).getPinyi();
   if (firstVisibleItem < 4) {
    text = name;
   } else {
    text = PingYinUtil.converterToFirstSpell(pinyin)
      .substring(0, 1).toUpperCase();
   }
   overlay.setText(text);
   overlay.setVisibility(View.VISIBLE);
   handler.removeCallbacks(overlayThread);
   // 延遲一秒後執行，讓overlay爲不可見
   handler.postDelayed(overlayThread, 1000);
  }
}
}

接下來這些可以直接複製不需要操作的類，DatabaseHelper.java跟DBHelper.java 實現的是查詢我們存儲城市文件的操作，在MyLetterListView.java中我們可以修改最右側邊欄的 a b c d 索引標籤，PingYinUtil.javaPingYinUtil.java這個類裏面實現的邏輯是拼音索引邏輯。詳細的可以看demo

demo 下載地址：http://download.csdn.net/detail/ningzhouxu/9533169 （這是我自己又修改後的版本）或者http://download.csdn.net/detail/ningzhouxu/9532845（這是美團原型）

仿美團實現城市定位。

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