listview无法按汉字首字母排序有关问题

package com.zhang.crm;import java.io.ByteArrayInputStream;import java.io.IOException;import java.io.InputStream;import com.zhang.R;import android.content.Context;import android.database.Cursor;import android.graphics.drawable.Drawable;import android.view.View;import android.widget.AlphabetIndexer;import android.widget.ImageView;import android.widget.SectionIndexer;import android.widget.SimpleCursorAdapter;public class testSimpleCursorAdapter extends SimpleCursorAdapter implements SectionIndexer{    private Cursor _cursor;    private Context _context;    AlphabetIndexer alphabetIndexer;        public testSimpleCursorAdapter(Context context, int layout, Cursor c,            String[] from, int[] to) {        super(context, layout, c, from, to);        _cursor = c;        _context= context;        alphabetIndexer = new AlphabetIndexer(_cursor, _cursor.getColumnIndexOrThrow(SystemConst.TABLE_FIELD_CLIENTNAME), " ABCDEFGHIJKLMNOPQRSTUVWXYZ");    }    @Override    public void bindView(View view, Context context, Cursor cursor) {        ImageView imageView = (ImageView)view.findViewById(R.id.image);        byte aa[] = new byte[1024*20];        int ch;        InputStream input = context.getResources().openRawResource(R.raw.listimage);        try {            do {                ch = input.read(aa);            } while (ch!=-1);                    } catch (IOException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }        ByteArrayInputStream stream = new ByteArrayInputStream(aa);        imageView.setImageDrawable(Drawable.createFromStream(stream, "img"));        super.bindView(view, context, cursor);    }    @Override    public int getPositionForSection(int section) {        return alphabetIndexer.getPositionForSection(section);    }    @Override    public int getSectionForPosition(int position) {//        return alphabetIndexer.getSectionForPosition(position);        return 0;    }    @Override    public Object[] getSections() {        if (alphabetIndexer != null) {             return alphabetIndexer.getSections();        } else {            return null;        }    }    }

cursor = getContentResolver().query(SystemConst.CONTENT_URI,null, null, null, null);        startManagingCursor(cursor);mIndexer = new CrmAlphabetIndexer(cursor, cursor.getColumnIndexOrThrow(SystemConst.TABLE_FIELD_CLIENTNAME), " ABCDEFGHIJKLMNOPQRSTUVWXYZ");        scAdapter = new testSimpleCursorAdapter(getApplicationContext(), R.layout.crmlist,                cursor, new String[]{SystemConst.TABLE_FIELD_CLIENTNAME,SystemConst.TABLE_FIELD_LINKMAN,SystemConst.TABLE_FIELD_TELPHONE},new int[]{R.id.clientName,R.id.linkName,R.id.telphone});        clientlist.setAdapter(scAdapter);