记得在我刚开始接触到美团网的时候就对美团网这个城市定位、选择城市功能很感兴趣，觉得它做得很棒。有如下几个点：
一：实现ListView的A-Z字母排序功能
二：根据输入框的输入值改变来过滤搜索结果，如果输入框里面的值为空，更新为原来的列表，否则为过滤数据列表
三：汉字转成拼音的功能，很多时候实现联系人或者城市列表等实现A-Z的排序功能，我们可以直接从数据库中获取他的汉字拼音，而对于一般的数据，我们怎么实现A-Z的排序，这里我使用了PinYin4j.jar将汉字转换为拼音.
按照惯例先来看一下最终效果图：
这里写图片描述
接下来分析下整个功能模块的布局结构：
（1）首先一个带删除按钮的EditText，我们在输入框中输入我们查找的城市可以自动过滤出最终的结果，当输入框中没有数据自动替换到原来的数据列表；
（2）中间是当前定位的城市和热门的城市，其中热门城市使用到了GridView；
（3）下面是一个ListView用来显示数据列表，右侧是一个字母索引表，当我们点击不同的字母,ListView会定位到该字母地方
现在我们来看下项目结构图
这里写图片描述
按照项目中类的顺序来一一介绍
1.PinYin4j.jar用于将汉字转换为拼音，你还可以使用其他方式将汉子转换为拼音，我之前有介绍过，这里就不详讲啦，探索PinYin4j.jar将汉字转换为拼音的基本用法
2.CitySortModel一个实体类，一个显示的城市和相对应的拼音首字母
package com.adan.selectcitydome.view;
public class CitySortModel {
private String name;//显示的数据
private String sortLetters;//显示数据拼音的首字母
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getSortLetters() {
return sortLetters;
}
public void setSortLetters(String sortLetters) {
this.sortLetters = sortLetters;
}
}
3.EditTextWithDel类是自定义的一个带清除功能的输入框控件,也可以用Android原生的EditText，这个类上一篇博客有介绍，这里就不贴上代码了Android 带清除功能的输入框控件EditTextWithDel
4.MyGridView类就是自定义GridView，主要是解决了在热门城市中嵌套Grideview的显示不完全的问题
package com.adan.selectcitydome.view;
import android.content.Context;
import android.util.AttributeSet;
import android.widget.GridView;
/**
* 自定义GridView，解决嵌套Grideview的显示不完全的问题
*/
public class MyGridView extends GridView {
public MyGridView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public MyGridView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public MyGridView(Context context) {
super(context);
}
/**
* 其中onMeasure函数决定了组件显示的高度与宽度；
* makeMeasureSpec函数中第一个函数决定布局空间的大小，第二个参数是布局模式
* MeasureSpec.AT_MOST的意思就是子控件需要多大的控件就扩展到多大的空间
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, expandSpec);
}
}
5.PinyinComparator类用来对ListView中的数据根据A-Z进行排序，前面两个if判断主要是将不是以汉字开头的数据放在后面
package com.adan.selectcitydome.view;
import java.util.Comparator;
/**
* 用来对ListView中的数据根据A-Z进行排序，前面两个if判断主要是将不是以汉字开头的数据放在后面
*/
public class PinyinComparator implements Comparator<CitySortModel> {
public int compare(CitySortModel o1, CitySortModel o2) {
//这里主要是用来对ListView里面的数据根据ABCDEFG...来排序
if (o1.getSortLetters().equals("@")
|| o2.getSortLetters().equals("#")) {
return -1;
} else if (o1.getSortLetters().equals("#")
|| o2.getSortLetters().equals("@")) {
return 1;
} else {
return o1.getSortLetters().compareTo(o2.getSortLetters());
}
}
}
6.PinyinUtils类，就是第一点所讲的PinYin4j.jar用于将汉字转换为拼音啦，这里就不粘贴代码啦
7.SideBar类就是ListView右侧的字母索引View，我们需要使用setTextView(TextView mTextDialog)来设置用来显示当前按下的字母的TextView,以及使用setOnTouchingLetterChangedListener方法来设置回调接口，在回调方法onTouchingLetterChanged(String s)中来处理不同的操作
package com.adan.selectcitydome.view;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.TextView;
import com.adan.selectcitydome.R;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/**
* ListView右侧的字母索引View
*/
public class SideBar extends View {
public static String[] INDEX_STRING = {"A", "B", "C", "D", "E", "F", "G", "H", "I",
"J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V",
"W", "X", "Y", "Z"};
private OnTouchingLetterChangedListener onTouchingLetterChangedListener;
private List<String> letterList;
private int choose = -1;
private Paint paint = new Paint();
private TextView mTextDialog;
public SideBar(Context context) {
this(context, null);
}
public SideBar(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public SideBar(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
setBackgroundColor(Color.parseColor("#F0F0F0"));
letterList = Arrays.asList(INDEX_STRING);
}
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int height = getHeight();// 获取对应高度
int width = getWidth();// 获取对应宽度
int singleHeight = height / letterList.size();// 获取每一个字母的高度
for (int i = 0; i < letterList.size(); i++) {
paint.setColor(Color.parseColor("#606060"));
paint.setTypeface(Typeface.DEFAULT_BOLD);
paint.setAntiAlias(true);
paint.setTextSize(20);
// 选中的状态
if (i == choose) {
paint.setColor(Color.parseColor("#4F41FD"));
paint.setFakeBoldText(true);
}
// x坐标等于中间-字符串宽度的一半.
float xPos = width / 2 - paint.measureText(letterList.get(i)) / 2;
float yPos = singleHeight * i + singleHeight / 2;
canvas.drawText(letterList.get(i), xPos, yPos, paint);
paint.reset();// 重置画笔
}
}
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
final int action = event.getAction();
final float y = event.getY();// 点击y坐标
final int oldChoose = choose;
final OnTouchingLetterChangedListener listener = onTouchingLetterChangedListener;
final int c = (int) (y / getHeight() * letterList.size());// 点击y坐标所占总高度的比例*b数组的长度就等于点击b中的个数.
switch (action) {
case MotionEvent.ACTION_UP:
setBackgroundColor(Color.parseColor("#F0F0F0"));
choose = -1;
invalidate();
if (mTextDialog != null) {
mTextDialog.setVisibility(View.GONE);
}
break;
default:
setBackgroundResource(R.drawable.sidebar_background);
if (oldChoose != c) {
if (c >= 0 && c < letterList.size()) {
if (listener != null) {
listener.onTouchingLetterChanged(letterList.get(c));
}
if (mTextDialog != null) {
mTextDialog.setText(letterList.get(c));
mTextDialog.setVisibility(View.VISIBLE);
}
choose = c;
invalidate();
}
}
break;
}
return true;
}
public void setIndexText(ArrayList<String> indexStrings) {
this.letterList = indexStrings;
invalidate();
}
/**
* 为SideBar设置显示当前按下的字母的TextView
*
* @param mTextDialog
*/
public void setTextView(TextView mTextDialog) {
this.mTextDialog = mTextDialog;
}
/**
* 向外公开的方法
*
* @param onTouchingLetterChangedListener
*/
public void setOnTouchingLetterChangedListener(
OnTouchingLetterChangedListener onTouchingLetterChangedListener) {
this.onTouchingLetterChangedListener = onTouchingLetterChangedListener;
}
/**
* 接口
*/
public interface OnTouchingLetterChangedListener {
void onTouchingLetterChanged(String s);
}
}
8.CityAdapter就是热门城市中GridView的适配器
package com.adan.selectcitydome;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.LinearLayout;
import java.util.List;
/**
* @author: xiaolijuan
* @description:
* @projectName: SelectCityDome
* @date: 2016-03-01
* @time: 17:25
*/
public class CityAdapter extends ArrayAdapter<String> {
/**
* 需要渲染的item布局文件
*/
private int resource;
public CityAdapter(Context context, int textViewResourceId, List<String> objects) {
super(context, textViewResourceId, objects);
resource = textViewResourceId;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
LinearLayout layout = null;
if (convertView == null) {
layout = (LinearLayout) LayoutInflater.from(getContext()).inflate(resource, null);
} else {
layout = (LinearLayout) convertView;
}
Button name = (Button) layout.findViewById(R.id.tv_city);
name.setText(getItem(position));
return layout;
}
}
9.SortAdapter 数据的适配器类，这里我们需要用到的就是SectionIndexer接口，它能够有效地帮助我们对分组进行控制。使用SectionIndexer接口需要实现三个方法：getSectionForPosition(int position)，getPositionForSection(int section)，getSections()，我们只需要自行实现前面两个方法：
（一）getSectionForPosition(int position)是根据ListView的position来找出当前位置所在的分组
getPositionForSection(int section)就是根据首字母的Char值来获取在该ListView中第一次出现该首字母的位置,也就是当前分组所在的位置
package com.adan.selectcitydome;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.SectionIndexer;
import android.widget.TextView;
import com.adan.selectcitydome.view.CitySortModel;
import java.util.List;
public class SortAdapter extends BaseAdapter implements SectionIndexer {
private List<CitySortModel> list = null;
private Context mContext;
public SortAdapter(Context mContext, List<CitySortModel> list) {
this.mContext = mContext;
this.list = list;
}
/**
* 当ListView数据发生变化时,调用此方法来更新ListView
*
* @param list
*/
public void updateListView(List<CitySortModel> list) {
this.list = list;
notifyDataSetChanged();
}
public int getCount() {
return this.list.size();
}
public Object getItem(int position) {
return list.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(final int position, View view, ViewGroup arg2) {
ViewHolder viewHolder = null;
final CitySortModel mContent = list.get(position);
if (view == null) {
viewHolder = new ViewHolder();
view = LayoutInflater.from(mContext).inflate(R.layout.item_select_city, null);
viewHolder.tvTitle = (TextView) view.findViewById(R.id.tv_city_name);
view.setTag(viewHolder);
viewHolder.tvLetter = (TextView) view.findViewById(R.id.tv_catagory);
} else {
viewHolder = (ViewHolder) view.getTag();
}
int section = getSectionForPosition(position);
if (position == getPositionForSection(section)) {
viewHolder.tvLetter.setVisibility(View.VISIBLE);
viewHolder.tvLetter.setText(mContent.getSortLetters());
} else {
viewHolder.tvLetter.setVisibility(View.GONE);
}
viewHolder.tvTitle.setText(this.list.get(position).getName());
return view;
}
final static class ViewHolder {
TextView tvLetter;
TextView tvTitle;
}
public int getSectionForPosition(int position) {
return list.get(position).getSortLetters().charAt(0);
}
public int getPositionForSection(int section) {
for (int i = 0; i < getCount(); i++) {
String sortStr = list.get(i).getSortLetters();
char firstChar = sortStr.toUpperCase().charAt(0);
if (firstChar == section) {
return i;
}
}
return -1;
}
@Override
public Object[] getSections() {
return null;
}
}
10.MainActivity 对EditTextWithDel设置addTextChangedListener监听，当输入框内容发生变化根据里面的值过滤ListView，里面的值为空显示原来的列表和给ListView添加表头等
package com.adan.selectcitydome;
import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import com.adan.selectcitydome.view.CitySortModel;
import com.adan.selectcitydome.view.EditTextWithDel;
import com.adan.selectcitydome.view.PinyinComparator;
import com.adan.selectcitydome.view.PinyinUtils;
import com.adan.selectcitydome.view.SideBar;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class MainActivity extends Activity {
private ListView sortListView;
private SideBar sideBar;
private TextView dialog, mTvTitle;
private SortAdapter adapter;
private EditTextWithDel mEtCityName;
private List<CitySortModel> SourceDateList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
}
private void initViews() {
mEtCityName = (EditTextWithDel) findViewById(R.id.et_search);
sideBar = (SideBar) findViewById(R.id.sidrbar);
dialog = (TextView) findViewById(R.id.dialog);
mTvTitle = (TextView) findViewById(R.id.tv_title);
sortListView = (ListView) findViewById(R.id.country_lvcountry);
initDatas();
initEvents();
setAdapter();
}
private void setAdapter() {
SourceDateList = filledData(getResources().getStringArray(R.array.provinces));
Collections.sort(SourceDateList, new PinyinComparator());
adapter = new SortAdapter(this, SourceDateList);
sortListView.addHeaderView(initHeadView());
sortListView.setAdapter(adapter);
}
private void initEvents() {
//设置右侧触摸监听
sideBar.setOnTouchingLetterChangedListener(new SideBar.OnTouchingLetterChangedListener() {
@Override
public void onTouchingLetterChanged(String s) {
//该字母首次出现的位置
int position = adapter.getPositionForSection(s.charAt(0));
if (position != -1) {
sortListView.setSelection(position + 1);
}
}
});
//ListView的点击事件
sortListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
mTvTitle.setText(((CitySortModel) adapter.getItem(position - 1)).getName());
Toast.makeText(getApplication(), ((CitySortModel) adapter.getItem(position)).getName(), Toast.LENGTH_SHORT).show();
}
});
//根据输入框输入值的改变来过滤搜索
mEtCityName.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
//当输入框里面的值为空，更新为原来的列表，否则为过滤数据列表
filterData(s.toString());
}
@Override
public void afterTextChanged(Editable s) {
}
});
}
private void initDatas() {
sideBar.setTextView(dialog);
}
private View initHeadView() {
View headView = getLayoutInflater().inflate(R.layout.headview, null);
GridView mGvCity = (GridView) headView.findViewById(R.id.gv_hot_city);
String[] datas = getResources().getStringArray(R.array.city);
ArrayList<String> cityList = new ArrayList<>();
for (int i = 0; i < datas.length; i++) {
cityList.add(datas[i]);
}
CityAdapter adapter = new CityAdapter(getApplicationContext(), R.layout.gridview_item, cityList);
mGvCity.setAdapter(adapter);
return headView;
}
/**
* 根据输入框中的值来过滤数据并更新ListView
*
* @param filterStr
*/
private void filterData(String filterStr) {
List<CitySortModel> mSortList = new ArrayList<>();
if (TextUtils.isEmpty(filterStr)) {
mSortList = SourceDateList;
} else {
mSortList.clear();
for (CitySortModel sortModel : SourceDateList) {
String name = sortModel.getName();
if (name.toUpperCase().indexOf(filterStr.toString().toUpperCase()) != -1 || PinyinUtils.getPingYin(name).toUpperCase().startsWith(filterStr.toString().toUpperCase())) {
mSortList.add(sortModel);
}
}
}
// 根据a-z进行排序
Collections.sort(mSortList, new PinyinComparator());
adapter.updateListView(mSortList);
}
private List<CitySortModel> filledData(String[] date) {
List<CitySortModel> mSortList = new ArrayList<>();
ArrayList<String> indexString = new ArrayList<>();
for (int i = 0; i < date.length; i++) {
CitySortModel sortModel = new CitySortModel();
sortModel.setName(date[i]);
String pinyin = PinyinUtils.getPingYin(date[i]);
String sortString = pinyin.substring(0, 1).toUpperCase();
if (sortString.matches("[A-Z]")) {
sortModel.setSortLetters(sortString.toUpperCase());
if (!indexString.contains(sortString)) {
indexString.add(sortString);
}
}
mSortList.add(sortModel);
}
Collections.sort(indexString);
sideBar.setIndexText(indexString);
return mSortList;
}
}
布局文件就不贴出来了，有兴趣的可以下载代码，有什么疑问的，请在下面留言，感谢各位_
本项目改造自http://blog.csdn.net/xiaanming/article/details/12684155
源代码请戳这里：Android 仿美团网,探索ListView的A-Z字母排序功能实现选择省份或者城市
