先上效果圖，呵呵，首先說明這個效果本人還是比較滿意的~
首先來分析一下頁面元素的，其實就是左側的一個listview和右側的一個自定義linearlayout，右側部分進行滑動時，左側的聯系人可以隨着字母進行移動。
這個效果用到的知識還是挺多的。然而“青青翠竹無非般若，郁郁黃花皆是妙諦”，認清了事務的內在規律都是不難，接着允許本人講一下~
1、普及知識，漢字轉gb2312碼和byte型數據
gb2312中的英文字符是與ascii碼一致的，一個字節。漢字字符是兩個字節，分為高八位和低八位：高字節的值為0xA0+區號，低字節的值為0xA0+位號。
漢字的區號值從16-87，位號值從1-94，（從這里我們可以算出來收錄的漢字數量為：69*94 = 6456個），從上表中，我們可以看到同一個拼音的漢字中間是斷代的，16-55區號的漢字的位號都是連續值，即所謂“一級漢字”（常用字），56-87區號的漢字位號是斷的，即“二級漢字”。實際上這個類就只能識別一級漢字，作者使用了一個簡單的障眼法，讓人不容易看明白，后面看筆者將其拆穿。
接下來看看byte型數據，因為類中使用了String.getBytes()，欲知漢字如何轉換為拼音，了解數據在內存中的存儲形式至關重要，基本的補碼知識請參考: http://perfect5085.iteye.com/blog/1612694;如果您確定了解補碼知識就可以往下看了：
咳咳，接下來，就是本人的測試程序來，來干什么呢？強化您的補碼知識...
public class Test { public static void main(String[] args){ String a = "啊";//啊的高字節（byte[0]）的值為0xA0+0x10= 0xB0 = 176（10進制） = 10110000
byte[] bytes = null;
byte mbyte= -80;
try { bytes = a.getBytes("gb2312"); }
catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block e.printStackTrace();
}
System.out.println(Integer.toBinaryString(bytes[0]));
System.out.println(Integer.toBinaryString(mbyte));
System.out.println(mbyte); } }
您可以先猜一下輸出值再看一下我的測試結果
注意！筆者的注釋是寫錯了的，或者是不完整，應該是這樣的一個過場，兩個十六進制的int值相加，結果為176，這個176的int值是正數，所以補碼還是176，末八位是10110000，但是通過getbytes（）轉化為byte值時，計算機在內存中直接將其補碼拿過來用，末八位仍然是10110000，所以輸出二進制時候直接把內存中的輸出來，但是輸出十進制時候計算機就不能直接輸出補碼了，他得把補碼還原成源碼，然后計算出對應的十進制數值來，即11010000、-80.
好了，惡補一頓開始我們的傳道授業解惑之旅吧~
我看先看這個拼音parser類：
package com.gensoft.autopet.fragment.bluetooth; /** * Java漢字轉換為拼音 */ public class CharacterParser { private static int[] pyvalue = new int[] {-20319, -20317, -20304, -20295, -20292, -20283, -20265, -20257, -20242, -20230, -20051, -20036, -20032, -20026, -20002, -19990, -19986, -19982, -19976, -19805, -19784, -19775, -19774, -19763, -19756, -19751, -19746, -19741, -19739, -19728, -19725, -19715, -19540, -19531, -19525, -19515, -19500, -19484, -19479, -19467, -19289, -19288, -19281, -19275, -19270, -19263, -19261, -19249, -19243, -19242, -19238, -19235, -19227, -19224, -19218, -19212, -19038, -19023, -19018, -19006, -19003, -18996, -18977, -18961, -18952, -18783, -18774, -18773, -18763, -18756, -18741, -18735, -18731, -18722, -18710, -18697, -18696, -18526, -18518, -18501, -18490, -18478, -18463, -18448, -18447, -18446, -18239, -18237, -18231, -18220, -18211, -18201, -18184, -18183, -18181, -18012, -17997, -17988, -17970, -17964, -17961, -17950, -17947, -17931, -17928, -17922, -17759, -17752, -17733, -17730, -17721, -17703, -17701, -17697, -17692, -17683, -17676, -17496, -17487, -17482, -17468, -17454, -17433, -17427, -17417, -17202, -17185, -16983, -16970, -16942, -16915, -16733, -16708, -16706, -16689, -16664, -16657, -16647, -16474, -16470, -16465, -16459, -16452, -16448, -16433, -16429, -16427, -16423, -16419, -16412, -16407, -16403, -16401, -16393, -16220, -16216, -16212, -16205, -16202, -16187, -16180, -16171, -16169, -16158, -16155, -15959, -15958, -15944, -15933, -15920, -15915, -15903, -15889, -15878, -15707, -15701, -15681, -15667, -15661, -15659, -15652, -15640, -15631, -15625, -15454, -15448, -15436, -15435, -15419, -15416, -15408, -15394, -15385, -15377, -15375, -15369, -15363, -15362, -15183, -15180, -15165, -15158, -15153, -15150, -15149, -15144, -15143, -15141, -15140, -15139, -15128, -15121, -15119, -15117, -15110, -15109, -14941, -14937, -14933, -14930, -14929, -14928, -14926, -14922, -14921, -14914, -14908, -14902, -14894, -14889, -14882, -14873, -14871, -14857, -14678, -14674, -14670, -14668, -14663, -14654, -14645, -14630, -14594, -14429, -14407, -14399, -14384, -14379, -14368, -14355, -14353, -14345, -14170, -14159, -14151, -14149, -14145, -14140, -14137, -14135, -14125, -14123, -14122, -14112, -14109, -14099, -14097, -14094, -14092, -14090, -14087, -14083, -13917, -13914, -13910, -13907, -13906, -13905, -13896, -13894, -13878, -13870, -13859, -13847, -13831, -13658, -13611, -13601, -13406, -13404, -13400, -13398, -13395, -13391, -13387, -13383, -13367, -13359, -13356, -13343, -13340, -13329, -13326, -13318, -13147, -13138, -13120, -13107, -13096, -13095, -13091, -13076, -13068, -13063, -13060, -12888, -12875, -12871, -12860, -12858, -12852, -12849, -12838, -12831, -12829, -12812, -12802, -12607, -12597, -12594, -12585, -12556, -12359, -12346, -12320, -12300, -12120, -12099, -12089, -12074, -12067, -12058, -12039, -11867, -11861, -11847, -11831, -11798, -11781, -11604, -11589, -11536, -11358, -11340, -11339, -11324, -11303, -11097, -11077, -11067, -11055, -11052, -11045, -11041, -11038, -11024, -11020, -11019, -11018, -11014, -10838, -10832, -10815, -10800, -10790, -10780, -10764, -10587, -10544, -10533, -10519, -10331, -10329, -10328, -10322, -10315, -10309, -10307, -10296, -10281, -10274, -10270, -10262, -10260, -10256, -10254}; public static String[] pystr = new String[] {"a", "ai", "an", "ang", "ao", "ba", "bai", "ban", "bang", "bao", "bei", "ben", "beng", "bi", "bian", "biao", "bie", "bin", "bing", "bo", "bu", "ca", "cai", "can", "cang", "cao", "ce", "ceng", "cha", "chai", "chan", "chang", "chao", "che", "chen", "cheng", "chi", "chong", "chou", "chu", "chuai", "chuan", "chuang", "chui", "chun", "chuo", "ci", "cong", "cou", "cu", "cuan", "cui", "cun", "cuo", "da", "dai", "dan", "dang", "dao", "de", "deng", "di", "dian", "diao", "die", "ding", "diu", "dong", "dou", "du", "duan", "dui", "dun", "duo", "e", "en", "er", "fa", "fan", "fang", "fei", "fen", "feng", "fo", "fou", "fu", "ga", "gai", "gan", "gang", "gao", "ge", "gei", "gen", "geng", "gong", "gou", "gu", "gua", "guai", "guan", "guang", "gui", "gun", "guo", "ha", "hai", "han", "hang", "hao", "he", "hei", "hen", "heng", "hong", "hou", "hu", "hua", "huai", "huan", "huang", "hui", "hun", "huo", "ji", "jia", "jian", "jiang", "jiao", "jie", "jin", "jing", "jiong", "jiu", "ju", "juan", "jue", "jun", "ka", "kai", "kan", "kang", "kao", "ke", "ken", "keng", "kong", "kou", "ku", "kua", "kuai", "kuan", "kuang", "kui", "kun", "kuo", "la", "lai", "lan", "lang", "lao", "le", "lei", "leng", "li", "lia", "lian", "liang", "liao", "lie", "lin", "ling", "liu", "long", "lou", "lu", "lv", "luan", "lue", "lun", "luo", "ma", "mai", "man", "mang", "mao", "me", "mei", "men", "meng", "mi", "mian", "miao", "mie", "min", "ming", "miu", "mo", "mou", "mu", "na", "nai", "nan", "nang", "nao", "ne", "nei", "nen", "neng", "ni", "nian", "niang", "niao", "nie", "nin", "ning", "niu", "nong", "nu", "nv", "nuan", "nue", "nuo", "o", "ou", "pa", "pai", "pan", "pang", "pao", "pei", "pen", "peng", "pi", "pian", "piao", "pie", "pin", "ping", "po", "pu", "qi", "qia", "qian", "qiang", "qiao", "qie", "qin", "qing", "qiong", "qiu", "qu", "quan", "que", "qun", "ran", "rang", "rao", "re", "ren", "reng", "ri", "rong", "rou", "ru", "ruan", "rui", "run", "ruo", "sa", "sai", "san", "sang", "sao", "se", "sen", "seng", "sha", "shai", "shan", "shang", "shao", "she", "shen", "sheng", "shi", "shou", "shu", "shua", "shuai", "shuan", "shuang", "shui", "shun", "shuo", "si", "song", "sou", "su", "suan", "sui", "sun", "suo", "ta", "tai", "tan", "tang", "tao", "te", "teng", "ti", "tian", "tiao", "tie", "ting", "tong", "tou", "tu", "tuan", "tui", "tun", "tuo", "wa", "wai", "wan", "wang", "wei", "wen", "weng", "wo", "wu", "xi", "xia", "xian", "xiang", "xiao", "xie", "xin", "xing", "xiong", "xiu", "xu", "xuan", "xue", "xun", "ya", "yan", "yang", "yao", "ye", "yi", "yin", "ying", "yo", "yong", "you", "yu", "yuan", "yue", "yun", "za", "zai", "zan", "zang", "zao", "ze", "zei", "zen", "zeng", "zha", "zhai", "zhan", "zhang", "zhao", "zhe", "zhen", "zheng", "zhi", "zhong", "zhou", "zhu", "zhua", "zhuai", "zhuan", "zhuang", "zhui", "zhun", "zhuo", "zi", "zong", "zou", "zu", "zuan", "zui", "zun", "zuo"}; private StringBuilder buffer; private String resource; private static CharacterParser characterParser = new CharacterParser(); public static CharacterParser getInstance() { return characterParser; } public String getResource() { return resource; } public void setResource(String resource) { this.resource = resource; } /** * 漢字轉成ASCII碼 * * @param chs * @return */ private int getChsAscii(String chs) { int asc = 0; try { byte[] bytes = chs.getBytes("gb2312"); if (bytes == null || bytes.length > 2 || bytes.length <= 0) { throw new RuntimeException("illegal resource string"); } if (bytes.length == 1) { asc = bytes[0]; } if (bytes.length == 2) { int hightByte = 256 + bytes[0]; int lowByte = 256 + bytes[1]; asc = (256 * hightByte + lowByte) - 256 * 256; } } catch (Exception e) { System.out.println("ERROR:ChineseSpelling.class-getChsAscii(String chs)" + e); } return asc; } /** * 單字解析 * * @param str * @return */ public String convert(String str) { String result = null; int ascii = getChsAscii(str); if (ascii > 0 && ascii < 160) { result = String.valueOf((char) ascii); } else { for (int i = (pyvalue.length - 1); i >= 0; i--) { if (pyvalue[i] <= ascii) { result = pystr[i]; break; } } } return result; } /** * 詞組解析 * * @param chs * @return */ public String getSpelling(String chs) { String key, value; buffer = new StringBuilder(); for (int i = 0; i < chs.length(); i++) { key = chs.substring(i, i + 1); if (key.getBytes().length >= 2) { value = (String) convert(key); if (value == null) { value = "unknown"; } } else { value = key; } buffer.append(value); } return buffer.toString(); } public String getSpelling() { return this.getSpelling(this.getResource()); } }
我們順着getSpelling(String chs)走，每次傳進來一個字符串，他把每個字符都檢出來，如果“utf-8”的編碼長度大於等於2，證明它是漢字，調用convert（key）方法，獲取他的拼音值，如果長度小於2，證明它不是漢字，直接獲取值，然后就這樣一個一個組合成字符串的拼音值。
convert（key）方法是如何獲取漢字的拼音值的呢？int ascii = getChsAscii(str); 它通過這個獲取到ascii（實際上應該是gb2312的編碼值，作者寫成acsii值，實在有點誤人子弟），然后去對照兩個大數組，通過ascii值來對應自己的拼音。
問題又來了，getChsAscii(str)是如何獲取到gb2312的編碼值的呢？看官且往下看，如果傳入字符的gb碼長度是1的話，那么肯定不是漢字，直接輸出，如果長度大於1的話，那么是漢字，然后通過String.getBytes()獲取它的高八位，和低八位，各加一個256還原成他們本來的“：高字節的值為0xA0+區號，低字節的值為0xA0+位號”，然后通過高八位*256+低八位獲取到他們原始的編碼值，這個值已經是唯一的了，此時作者畫蛇已成，顯然有點飄飄然，欣欣然地加上了一句：-256*256，於是所有的值都變成負數了，然后害得如果你是東北人，就可能要“尋思”一番了。
到此為止，輸入一個漢字，我們應該了解了是如何得到一個漢字了，以上只是作者對於“一級漢字”的支持，二級漢字顯然是處理麻煩了一些，完全可以實現，但是需要很多判斷，如果您想拓展到此完全可以自己實現了。
接下來就是往列表中加載數據了，當然用到的是android最經典的adapter，來看我們的adpater類：
public class SortAdapter extends BaseAdapter implements SectionIndexer{ private List<SortModel> list = null; private Context mContext; public SortAdapter(Context mContext, List<SortModel> list) { this.mContext = mContext; this.list = list; } /** * 當ListView數據發生變化時,調用此方法來更新ListView * @param list */ public void updateListView(List<SortModel> 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) { final SortModel mContent = list.get(position); View rootView = LayoutInflater.from(mContext).inflate(R.layout.bluet_contract_item, arg2,false); TextView tvTitle = (TextView) rootView.findViewById(R.id.title); TextView tvLetter = (TextView) rootView.findViewById(R.id.catalog); //根據position獲取分類的首字母的char ascii值 int section = getSectionForPosition(position); //如果當前位置等於該分類首字母的Char的位置 ，則認為是第一次出現 if(position == getPositionForSection(section)){ tvLetter.setVisibility(View.VISIBLE); tvLetter.setText(mContent.getSortLetters()); }else{ tvLetter.setVisibility(View.GONE); } tvTitle.setText(this.list.get(position).getName()); return rootView; } /** * 根據ListView的當前位置獲取分類的首字母的char ascii值 */ public int getSectionForPosition(int position) { return list.get(position).getSortLetters().charAt(0); } /** * 根據分類的首字母的Char ascii值獲取其第一次出現該首字母的位置 */ 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; }
傳入參數為一個根據拼音首字母排序好了的列表，泛型為SortModel的類型，getview()進行渲染時候，每到一個position，就獲取對應項的首字母，然后查這個首字母在列表的位置，如果此position等於彼position，然后證明這個是第一個攜帶該首字母出現的，然后在布局中把"ABCDEF"之類的字母顯示出來，如果不等於，那么就只顯示數據了。
順便發下布局文件和SortModel類
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center_vertical" android:orientation="vertical" > <TextView android:id="@+id/catalog" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="#E0E0E0" android:textColor="#454545" android:layout_weight="1.0" android:paddingLeft="5dip" android:paddingTop="5dip" android:paddingBottom="5dip" /> <TextView android:id="@+id/title" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center_vertical" android:layout_weight="1.0" android:textColor="#336598" android:layout_marginLeft="5dip" android:paddingTop="10dip" android:paddingBottom="10dip" /> </LinearLayout>
public class SortModel { private String name; //顯示的數據 private String sortLetters; //顯示數據拼音的字母 private String phoneNumber;//聯系人的手機號 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; } public String getPhoneNumber() { return phoneNumber; } public void setPhoneNumber(String phoneNumber) { this.phoneNumber = phoneNumber; } }
然后我們來看看主頁面加載的時候，是如何把初始的數據按次序加載到列表上的。
public class BluetoothFragment extends Fragment{ private ListView telephonyListView; private SideBar sideBar; /** * 漢字轉換成拼音 */ private CharacterParser characterParser; private List<SortModel> SourceDateList; // 聯系人列表填充數據 private SortAdapter contractsAdapter;// 聯系人列表適配器 /** * 根據拼音來排列ListView里面的數據類 */ private PinyinComparator pinyinComparator; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { // TODO Auto-generated method stub telephonyListView = (ListView) view.findViewById(R.id.bluet_telephony_listview); String[] nameStrings = new String[]{"明明","剛剛","軍軍","紅紅","花花","冷冷","妍妍","特特","貝貝","愛愛","憐憐","采采"}; String[] phoneStrings = new String[]{"19837472999","15884578834","34567866643","12343254323","34521233367","34512322213","65432344456","34567866643","12343254323","34521233367","34512322213","65432344456"}; SourceDateList = filledData(nameStrings,phoneStrings); Collections.sort(SourceDateList,pinyinComparator); contractsAdapter = new SortAdapter(getActivity(),SourceDateList); telephonyListView.setAdapter(contractsAdapter); } /** * 為ListView填充數據 * * @param data * @param phoneNumber * @return */ private List<SortModel> filledData(String[] data, String[] phoneNumber) { List<SortModel> mSortList = new ArrayList<SortModel>(); for (int i = 0; i < data.length; i++) { SortModel sortModel = new SortModel(); sortModel.setName(data[i]); sortModel.setPhoneNumber(phoneNumber[i]); // 漢字轉換成拼音 String pinyin = characterParser.getSpelling(data[i]); String sortString = pinyin.substring(0, 1).toUpperCase(Locale.getDefault()); // 正則表達式，判斷首字母是否是英文字母 if (sortString.matches("[A-Z]")) { sortModel.setSortLetters(sortString.toUpperCase(Locale.getDefault())); } else { sortModel.setSortLetters("#"); } mSortList.add(sortModel); } return mSortList; } }
初始數據通過filledData()組成一個list，里邊是一個一個的sortmodel，通過對name屬性得到拼音，再得到首字母，然后用到一個正則表達式match("[A-Z]"),如果首字母是a-z的字符，則把該sortmodel對象的sortLetters屬性設為原字符，否則就設為 "#"，好了list創建完畢了，但是要適配的adapter上，還需要，還需要什么？對！就是我們的排序，這里又用到了我們的PinyinComparator工具類：
public class PinyinComparator implements Comparator<SortModel> { public int compare(SortModel o1, SortModel o2) { //這里主要是用來對ListView里面的數據根據ABCDEFG...來排序 if (o2.getSortLetters().equals("#")) { return -1; } else if (o1.getSortLetters().equals("#")) { return 1; } else { return o1.getSortLetters().compareTo(o2.getSortLetters()); } } }
Comparator的原理就是運用compare的返回值來比較前后兩者的大小，返回負值說明前者的小於后者，返回正值說明前者大於后者，返回0證明兩者相等，原生的compare方法總是通過unicode碼比較兩者大小，排序后的列表是按照升序排列的。
到此為止，我們的列表部分算是已經完成了。
接下來看看我們的自定義組件SideBar
public class SideBar extends View { // 觸摸事件 private OnTouchingLetterChangedListener onTouchingLetterChangedListener; // 26個字母 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;// 選中 private Paint paint = new Paint(); private TextView mTextDialog; /** * 為SideBar設置顯示字母的TextView * @param mTextDialog */ public void setTextView(TextView mTextDialog) { this.mTextDialog = mTextDialog; } public SideBar(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public SideBar(Context context, AttributeSet attrs) { super(context, attrs); } public SideBar(Context context) { super(context); } /** * 重寫這個方法 */ protected void onDraw(Canvas canvas) { super.onDraw(canvas); // 獲取焦點改變背景顏色. int height = getHeight();// 獲取對應高度 int width = getWidth(); // 獲取對應寬度 int singleHeight = height / b.length;// 獲取每一個字母的高度 for (int i = 0; i < b.length; i++) { paint.setColor(Color.rgb(33, 65, 98)); // paint.setColor(Color.WHITE); paint.setTypeface(Typeface.DEFAULT_BOLD); paint.setAntiAlias(true); paint.setTextSize(12); // 選中的狀態 if (i == choose) { paint.setColor(Color.parseColor("#3399ff")); paint.setFakeBoldText(true); } // x坐標等於中間-字符串寬度的一半. float xPos = width / 2 - paint.measureText(b[i]) / 2; float yPos = singleHeight * i + singleHeight; canvas.drawText(b[i], xPos, yPos, paint); paint.reset();// 重置畫筆 } } @SuppressLint("NewApi") @Override public boolean dispatchTouchEvent(MotionEvent event) { final int action = event.getAction(); final float y = event.getY();// 點擊y坐標 final int oldChoose = choose; final OnTouchingLetterChangedListener listener = onTouchingLetterChangedListener; final int c = (int) (y / getHeight() * b.length);// 點擊y坐標所占總高度的比例*b數組的長度就等於點擊b中的個數. switch (action) { case MotionEvent.ACTION_UP: setBackgroundDrawable(new ColorDrawable(0x00000000)); choose = -1;// invalidate(); if (mTextDialog != null) { mTextDialog.setVisibility(View.INVISIBLE); } break; default: setBackground(new ColorDrawable(Color.MAGENTA)); 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; } /** * 向外公開的方法 * * @param onTouchingLetterChangedListener */ public void setOnTouchingLetterChangedListener( OnTouchingLetterChangedListener onTouchingLetterChangedListener) { this.onTouchingLetterChangedListener = onTouchingLetterChangedListener; } /** * 接口 * * @author coder * */ public interface OnTouchingLetterChangedListener { public void onTouchingLetterChanged(String s); } }
這個sidebar只是重寫了ondraw和dispatchTouchEvent方法，其實對於一個不是viewgroup的view來說，因為不涉及給子View分配ontouch事件的邏輯，重寫dispatchTouchEvent和ontouch方法其實是一樣的，而且本次重寫會多次在dispatchTouchEvent中調用invalidate方法調用ondraw，我們就先來分析這個invalidate方法：
我在觸摸屏幕沒有松開手指走到“default:”這個地方，如果我觸摸的區域不是原來的字母區域，這時候我如果綁定了listener的話，會做回調listener中的方法的操作， 如果你為這個sidebar綁定了textview，他還要控制textview的文字和顯隱。final int c = (int) (y / getHeight() * b.length); 這個c值記錄了當前觸摸到的是哪一個字母，然后調用ondraw刷新view，如果你松開了手指，那就走到了case MotionEvent.ACTION_UP這里，然后把choose變成-1，刷新view，從這里我們其實可以猜出來，在ondraw中肯定是根據choose的值，去動態刷新view的，那么具體是怎么做的呢？
其實就是根據choose的值，在手指觸摸到的那個字母上，改變畫筆的屬性，畫出來和別的字母顏色不一樣的字母罷了。
sideBar.setTextView(sideText); // 設置右側觸摸監聽 sideBar.setOnTouchingLetterChangedListener(new OnTouchingLetterChangedListener() { @Override public void onTouchingLetterChanged(String s) { // 該字母首次出現的位置 if (contractsAdapter != null) { int position = contractsAdapter.getPositionForSection(s.charAt(0)); if (position != -1) { telephonyListView.setSelection(position); } } } });
其實剛才的fragment的oncreate方法中少寫了上面的一段代碼，是初始化sidebar用的，在listener中調用刷新列表的方法，然后我們就可以看到如文章開始時刻的畫面了 >_<
by the way，您能看完這個博文，證明您已經很努力地再看了，以本人拙劣的表述還要寫這么長的文章 是不是很捉急啊？