因为项目需要字母索引排序的效果，GIT上和博客上有很多，但是发现很多DEMO的效果和自己想要的有出入，所以稍微整理了一下。
这篇就是在整理过程中自己写的测试Demo。
先上截图（字符串是随机生成的，部分视觉效果也进行了处理……修复了Bug，但是搜索的效率太低，搜索实现的另一种方法，在下一篇博客中）。
说明：顶部是搜索部分，右边是自定义的字母索引MyLetterSortView，中间的是展示数据的ListView。
先看字母索引MyLetterSortView：
<pre name="code" class="java">public class MyLetterSortView extends View {
// 触摸事件
private OnTouchingLetterChangedListener onTouchingLetterChangedListener;
// 26个字母
public static String[] b = { "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 int choose = -1;// 选中
private Paint paint = new Paint();
private TextView mTextDialog;
public void setTextView(TextView mTextDialog) {
this.mTextDialog = mTextDialog;
}
public MyLetterSortView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public MyLetterSortView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public MyLetterSortView(Context context) {
super(context);
}
/**
* 重写这个方法
*/
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// 获取焦点改变背景颜色.
int height = getHeight();// 获取对应高度
int width = getWidth(); // 获取对应宽度
int singleHeight = height / b.length;// 获取每一个字母的高度
for (int i = 0; i < b.length; i++) {
paint.setColor(Color.parseColor("#9da0a4"));
paint.setTypeface(Typeface.DEFAULT_BOLD);
paint.setAntiAlias(true);
// paint.setTextSize(PixelUtil.sp2px(12));
paint.setTextSize(25);
// 选中的状态
if (i == choose) {
paint.setColor(Color.parseColor("#3399ff"));
paint.setFakeBoldText(true);
}
// x坐标等于中间-字符串宽度的一半.
float xPos = width / 2 - paint.measureText(b[i]) / 2;
float yPos = singleHeight * i + singleHeight;
canvas.drawText(b[i], xPos, yPos, paint);
paint.reset();// 重置画笔
}
}
@SuppressWarnings("deprecation")
@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() * b.length);// 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:
setBackgroundDrawable(new ColorDrawable(0x00000000));
choose = -1;//
invalidate();
if (mTextDialog != null) {
mTextDialog.setVisibility(View.INVISIBLE);
}
break;
default:
//设置右侧字母列表[A,B,C,D,E....]的背景颜色
setBackgroundResource(R.drawable.letter_sort_background);
if (oldChoose != c) {
if (c >= 0 && c < b.length) {
if (listener != null) {
listener.onTouchingLetterChanged(b[c]);
}
if (mTextDialog != null) {
mTextDialog.setText(b[c]);
mTextDialog.setVisibility(View.VISIBLE);
}
choose = c;
invalidate();
}
}
break;
}
return true;
}
/**
* 向外公开的方法
*
* @param onTouchingLetterChangedListener
*/
public void setOnTouchingLetterChangedListener(
OnTouchingLetterChangedListener onTouchingLetterChangedListener) {
this.onTouchingLetterChangedListener = onTouchingLetterChangedListener;
}
public interface OnTouchingLetterChangedListener {
public void onTouchingLetterChanged(String s);
}
}
再看看布局activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<com.example.testbase.ClearEditText
android:id="@+id/et_msg_search"
android:layout_width="match_parent"
android:layout_height="48.0dip"
android:background="@drawable/base_edit_input"
android:drawableLeft="@drawable/icon_msg_search"
android:drawablePadding="10dp"
android:hint="@string/message_search_hint"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:singleLine="true" />
<RelativeLayout
android:id="@+id/layout_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/base_bg"
android:orientation="vertical" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="top"
android:background="@drawable/content_bg"
android:orientation="horizontal" >
<ListView
android:id="@+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:cacheColorHint="#00000000"
android:scrollbars="none" />
<TextView
android:id="@+id/tv_mid_letter"
android:layout_width="80.0dip"
android:layout_height="80.0dip"
android:layout_centerInParent="true"
android:layout_gravity="center"
android:background="@drawable/letter_mid_view_background"
android:gravity="center"
android:padding="5dip"
android:textColor="@color/base_actionbar_bg"
android:textSize="35.0dip"
android:visibility="invisible" />
</RelativeLayout>
<com.example.testbase.MyLetterSortView
android:id="@+id/right_letter"
android:layout_width="25dip"
android:layout_height="match_parent"
android:layout_alignParentRight="true"
android:background="@color/transparent" />
</RelativeLayout>
</LinearLayout>为了测试带有汉字，数字，字母的字符串排序，就写了一个随机字符串工具StringRandomUtils：
public class StringRandomUtils {
private Random widthRandom = new Random();
private int length;
private static char[] charsNumber = ("0123456789").toCharArray();
private static char[] charsLetter = ("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ").toCharArray();
private static char[] charsRandom = ("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ").toCharArray();
private static Random random = new Random();
//参数为生成的字符串的长度，根据给定的char集合生成字符串数字
public static String randomNumber(int length){
char[] data = new char[length];
for(int i = 0;i < length;i++){
int index = random.nextInt(charsNumber.length);
data[i] = charsNumber[index];
}
String s = new String(data);
return s;
}
//参数为生成的字符串的长度，根据给定的char集合生成字符串 字母
public static String randomLetter(int length){
char[] data = new char[length];
for(int i = 0;i < length;i++){
int index = random.nextInt(charsLetter.length);
data[i] = charsLetter[index];
}
String s = new String(data);
return s;
}
//参数为生成的字符串的长度，根据给定的char集合生成字符串
public static String getStringRandom(int length){
char[] data = new char[length];
for(int i = 0;i < length;i++){
int index = random.nextInt(charsRandom.length);
data[i] = charsRandom[index];
}
String s = new String(data);
return s;
}
//简体中文
public static String getRandomJianHan(int len)
{
String ret="";
for(int i=0;i<len;i++){
String str = null;
int hightPos, lowPos; // 定义高低位
Random random = new Random();
hightPos = (176 + Math.abs(random.nextInt(39))); //获取高位值
lowPos = (161 + Math.abs(random.nextInt(93))); //获取低位值
byte[] b = new byte[2];
b[0] = (new Integer(hightPos).byteValue());
b[1] = (new Integer(lowPos).byteValue());
try
{
str = new String(b, "GBk"); //转成中文
}
catch (UnsupportedEncodingException ex)
{
ex.printStackTrace();
}
ret+=str;
}
return ret;
}
}
可以随机生成简体汉字的字符串，纯阿拉伯数字的字符串，纯字母的字符串，数字和字母组合的字符串，方便模拟测试数据。
实体ItemBean定义三个字段，用于排序的sortLetters，username和头像avatar。
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public class ItemBean {
/**
* 显示数据拼音的首字母
*/
private String sortLetters;
String username;
String avatar;
public String getSortLetters() {
return sortLetters;
}
public void setSortLetters(String sortLetters) {
this.sortLetters = sortLetters;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getAvatar() {
return avatar;
}
public void setAvatar(String avatar) {
this.avatar = avatar;
}
}
至于ItemBeanAdapter，需要实现SectionIndexer接口，重写getSections()和getSectionForPosition（）方法即可，这里代码就不贴了。
再来看看LetterSortActivity：
public class LetterSortActivity extends Activity implements OnClickListener {
public static final String TAG = LetterSortActivity.class.getSimpleName();
private Context context = LetterSortActivity.this;
private ClearEditText mClearEditText;
private TextView tv_mid_letter;
private ListView listView;
private MyLetterSortView right_letter;
private ItemBeanAdapter mAdapter;
private List<ItemBean> mlist = new ArrayList<ItemBean>();
private InputMethodManager inputMethodManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
setLinstener();
initData();
fillData();
}
protected void initData() {
getData();
mAdapter = new ItemBeanAdapter(this, mlist);
listView.setAdapter(mAdapter);
}
protected void initView() {
inputMethodManager = (InputMethodManager) this
.getSystemService(Context.INPUT_METHOD_SERVICE);
listView = (ListView) findViewById(R.id.list);
mClearEditText = (ClearEditText) findViewById(R.id.et_msg_search);
// 这里设置中间字母
right_letter = (MyLetterSortView) findViewById(R.id.right_letter);
tv_mid_letter = (TextView) findViewById(R.id.tv_mid_letter);
right_letter.setTextView(tv_mid_letter);
}
protected void setLinstener() {
// tv_reget_pwd.setOnClickListener(this);
listView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
T.showShort(getApplicationContext(), ((ItemBean) mAdapter
.getItem(position)).getUsername());
}
});
listView.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
// 隐藏软键盘
if (getWindow().getAttributes().softInputMode != WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN) {
if (getCurrentFocus() != null)
inputMethodManager.hideSoftInputFromWindow(
getCurrentFocus().getWindowToken(),
InputMethodManager.HIDE_NOT_ALWAYS);
}
return false;
}
});
// 设置右侧触摸监听
right_letter
.setOnTouchingLetterChangedListener(new OnTouchingLetterChangedListener() {
@Override
public void onTouchingLetterChanged(String s) {
// 该字母首次出现的位置
int position = mAdapter.getPositionForSection(s
.charAt(0));
if (position != -1) {
listView.setSelection(position );
}
}
});
// 根据输入框输入值的改变来过滤搜索
mClearEditText.addTextChangedListener(new TextWatcher() {
@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 beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
@Override
public void afterTextChanged(Editable s) {
}
});
}
protected void fillData() {
// TODO Auto-generated method stub
}
private void getData() {
mlist.clear();
// 随机生成40个简体汉字字符串
for (int i = 0; i < 40; ++i) {
ItemBean uBean = new ItemBean();
String str1 = StringRandomUtils.getRandomJianHan(5);
String ch1 = ((CharacterParser.getInstance().getSelling(str1))
.toUpperCase()).substring(0, 1);
uBean.setSortLetters(ch1);
uBean.setUsername(str1);
mlist.add(uBean);
}
// 随机生成40个字母数字组合字符串
for (int i = 0; i < 40; ++i) {
ItemBean uBean = new ItemBean();
String str1 = StringRandomUtils.getStringRandom(5);
String ch1 = ((CharacterParser.getInstance().getSelling(str1))
.toUpperCase()).substring(0, 1);
uBean.setSortLetters(ch1);
uBean.setUsername(str1);
mlist.add(uBean);
}
// 对list进行排序
Collections.sort(mlist, new PinyinComparator() {
});
}
/**
* 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<ItemBean> filterDateList = new ArrayList<ItemBean>();
if (TextUtils.isEmpty(filterStr)) {
mAdapter.updateListView(mlist);
} else {
filterDateList.clear();
for (ItemBean sortModel : mlist) {
String name = sortModel.getUsername();
if (name != null) {
if (name.indexOf(filterStr.toString()) != -1
|| CharacterParser.getInstance().getSelling(name)
.startsWith(filterStr.toString())) {
filterDateList.add(sortModel);
}
}
}
Collections.sort(filterDateList, new PinyinComparator() {
});
mAdapter.updateListView(filterDateList);
}
}
@Override
public void onClick(View v) {
switch (v.getId()) {
//
default:
break;
}
}
}
首先 通过getData()初始化测试数据，一共80条，再通过Collections.sort(mlist, new PinyinComparator()）排序，然后把数据源放在Adapter中即可。
至于搜索，仍然是先筛选出条件数据，再进行排序，不过这样效率是在不敢恭维，数据量少的话，或许感觉不出来，但是一遇到几千条数据要等好几秒，在下一篇博客中将使用Filterable的getFilter()实现数据过滤，效率要高不少。
好了，上面的代码很好理解，就不多说了。
Demo下载地址：http://download.csdn.net/detail/yalinfendou/8615325