这两天看了个Demo，自己也动手写了下，觉得效果还不错，分享一下！

主要是利用ListActivity中自带了一个ListView和ListAdapter来实现的，当然也可以在一般的Activity中添加ListView和ListAdapter来实现。具体代码如下：

显示自定义的适配器的实现：

//HomeScreenAdapter.csusing System;using System.Collections.Generic;using System.Linq;using System.Text;using Android.App;using Android.Content;using Android.OS;using Android.Runtime;using Android.Views;using Android.Widget;namespace ListViewAdapter{    [Activity(Label = "ListViewAdapter")]    public class HomeScreenAdapter : BaseAdapter
     
          {        private string[] items;        private Activity context;        public HomeScreenAdapter(Activity context, string[] items)            : base()        {            this.context = context;            this.items = items;        }        public override string this[int position]        {            get { return items[position]; }        }        public override int Count        {            get { return items.Length; }        }        public override long GetItemId(int position)        {            return position;        }        public override View GetView(int position, View convertView, ViewGroup parent)        {            View view = convertView;            if (view == null)            {                view = context.LayoutInflater.Inflate(Android.Resource.Layout.SimpleListItem1, null);            }            view.FindViewById
      
       (Android.Resource.Id.Text1).Text = items[position];            return view;        }    }}
      
     

自定义适配器实现之后，只要将它赋给ListActivity中ListAdapter成员就可以了。

下面看看主类HomeScreen.cs的实现：

using System;using System.Collections.Generic;using System.IO;using System.Text;using Android.App;using Android.Content;using Android.Runtime;using Android.Views;using Android.Widget;using Android.OS;namespace SectionIndex{    [Activity(Label = "SectionIndex", MainLauncher = true, Icon = "@drawable/icon")]    public class HomeScreen : ListActivity    {        private string[] items;        protected override void OnCreate(Bundle bundle)        {            base.OnCreate(bundle);                        //用于存放文本文件的List            List
      
        veges = new List
       
        ();            //利用流来打开文本文件            Stream seedDataStream = Assets.Open(@"VegeData.txt");            //将文本文件内容读入veges中            //StringBuilder sb = new StringBuilder();            using (StreamReader reader = new StreamReader(seedDataStream))            {                while (!reader.EndOfStream)                {                    veges.Add(reader.ReadLine());                }            }            //将veges中的元素进行排序,比较器为匿名函数构成的委托            veges.Sort((x,y)=>{ return x.CompareTo(y); } );            //将列表中的元素存入数组中            items = veges.ToArray();        }        protected override void OnListItemClick(ListView l, View v, int position, long id)        {            var t = items[position];            Toast.MakeText(this, t, ToastLength.Short).Show();            Console.WriteLine("Clicked on: " + t);        }    }}
       
      

　　其中VegesData.txt为要读取的文本文件：其内容如下：

Beet greensBitterleafBok choyBroccoli RabeBrussels sproutCabbageCatsearCeleryCeltuceCeylon spinachChardChayaChickweedChicoryChinese cabbageChinese MallowChrysanthemum leavesCollard greensCorn saladCressDandelionEndiveEpazoteFat henFiddleheadFluted pumpkinGarden RocketGolden samphireGood King HenryGreater PlantainKai-lanKaleKomatsunaKukaLagos bologiLamb's lettuceLand cressLettuceLizard's tailMelokhiaMizuna greensMustardNapa cabbageNew Zealand SpinachOrachePak choyParacressPea sprouts/leavesPokeRadicchioSamphireSea beetSea kaleSierra Leone bologiSokoSorrelSpinachSummer purslaneSwiss chardTatsoiTurnip greensWatercressWater spinachWinter purslaneYarrowAvocadoBell pepperBitter melon/Bitter gourdCourgetteCucumberIvy GourdEggplant/Aubergine/BrinjalPumpkinSquashSweet corn aka corn; aka maizeSweet pepperTindaTomatilloTomatoWinter melonWest Indian gherkinZucchiniArtichokeBroccoliCauliflowerCourgette flowersSquash blossomsAmerican groundnutAzuki beanBlack-eyed peaChickpeaCommon beanDrumstickDolichos beanFava beanGarbanzoGreen beanGuarGumboHorse gramIndian peaLentilLima BeanMoth beanMung beanOkraPeaPeanutPigeon peaRicebeanRunner beanSnap peaSnow peaSoybeanTarwiTepary beanUrad beanVelvet beanWinged beanYardlong beanAsparagusCardoonCeleriacCeleryElephant GarlicFlorence fennelGarlicKohlrabiKurratLeekLotus rootNopalOnionSpring Onion/ScallionPrussian asparagusShallotWelsh onionWild leekAhipaArracachaBamboo shootBeetrootBurdockBroadleaf arrowheadCamasCannaCarrotCassavaChinese artichokeDaikonEarthnut peaElephant Foot yamEnseteGingerGoboHamburg parsleyJerusalem artichokeJícamaManiocMooliParsnipPignutPlectranthusPotatoPrairie turnipRadishHorseradishRutabagaSalsifyScorzoneraSkirretSwedeSweet Potato or KumaraTaroTiTigernutTurnipUllucoWater chestnutYacónYam

　　关键部分就是如何实现ISectionIndexer这个接口。