列表视图使用的CursorAdapter

问题描述

林发展其与CursorAdapter中显示手机通讯录的应用程序。当我运行它，我面对着这只是重复一个联系人为波纹管列表视图（大卫是我接触的一个，只是重复列表视图）

大卫017224860

大卫017224860

大卫017224860

大卫017224860

大卫017224860

大卫017224860

。

我的行为看起来像

 公共类联系方式延伸活动{
@覆盖
保护无效的onCreate（包savedInstanceState）{
    super.onCreate（savedInstanceState）;
    的setContentView（R.layout.contacts）;

光标光标=
     getContentResolver（）查询（ContactsContract.CommonDataKinds.Phone.CONTENT_URI，
     NULL，NULL，NULL，NULL）;
    startManagingCursor（光标）;
     ContactCursorAdapterCT适配器=新ContactCursorAdapterCT（Contacts.this，光标）;
     ListView控件contactLV =（ListView控件）findViewById（R.id.listviewblcontactsDB）;

      contactLV.setAdapter（适配器）;
 

和我的CursorAdapter是这样的：

 公共类ContactCursorAdapterCT扩展的CursorAdapter {
       公共ContactCursorAdapterCT（上下文的背景下，光标C）{
    超（背景下，C）;
    // TODO自动生成构造函数存根
}

@覆盖
公共无效bindView（查看视图，上下文的背景下，光标光标）{

    而（cursor.moveToNext（））{

    TextView的名称=（TextView中）view.findViewById（R.id.blacklistDB1）;
          name.setText（cursor.getString（cursor.getColumnIndex
          （ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME）））;

          TextView的手机=（TextView中）view.findViewById（R.id.blacklistDB2）;
          phone.setText（cursor.getString（cursor.getColumnIndex
          （ContactsContract.CommonDataKinds.Phone.NUMBER）））;

}
}

@覆盖
公共查看NewView的（上下文的背景下，光标光标的ViewGroup父）{
    // TODO自动生成方法存根

    LayoutInflater充气= LayoutInflater.from（上下文）;

    视图V = inflater.inflate（R.layout.lv，父母，假）;
            bindView（ⅴ，上下文，光标）;
           返回伏;
        }
 

解决方案

我注意到几点：

1. 系统的CursorAdapter移动光标你，拿出你调用 cursor.moveToNext（）。
2. 在适配器的 getView（）电话 NewView的（）和 bindView（）在它自己的;你不应该调用这些方法吧。
3. 您应该看在Android开发者的讲座谷歌IO 了解有关加快适配器的技巧和窍门。温馨提示，如：
   • 使用ViewHolder，而不是调用 findViewById（）反复。
   • 重复保存光标的指标，而不是调用 getColumnIndex（）。
   • 取回的LayoutInflater一次，并保持局部引用。

Im developing an application which display Phone contacts with CursorAdapter.When I run it, i faced with a list view which repeated just one contact as bellow ("david" is one of the my contacts, just repeated in listview)

david017224860

david017224860

david017224860

david017224860

david017224860

david017224860 .

.

.

.

My activity looks like

public class Contacts extends Activity {    
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.contacts);

Cursor cursor = 
     getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,
     null,  null,null, null);
    startManagingCursor(cursor);
     ContactCursorAdapterCT adapter= new ContactCursorAdapterCT(Contacts.this, cursor);
     ListView contactLV = (ListView) findViewById(R.id.listviewblcontactsDB);

      contactLV.setAdapter(adapter);

And my cursorAdapter looks like:

public class ContactCursorAdapterCT extends CursorAdapter {
       public ContactCursorAdapterCT(Context context, Cursor c) {
    super(context, c);
    // TODO Auto-generated constructor stub
}

@Override
public void bindView(View view, Context context, Cursor cursor) {

    while (cursor.moveToNext()) {

    TextView name = (TextView)view.findViewById(R.id.blacklistDB1);               
          name.setText(cursor.getString(cursor.getColumnIndex
          (ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME)));

          TextView phone = (TextView)view.findViewById(R.id.blacklistDB2); 
          phone.setText(cursor.getString(cursor.getColumnIndex
          (ContactsContract.CommonDataKinds.Phone.NUMBER)));

}
}

@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
    // TODO Auto-generated method stub

    LayoutInflater inflater = LayoutInflater.from(context);

    View v = inflater.inflate(R.layout.lv, parent, false);
            bindView(v, context, cursor);
           return v;
        }

解决方案

I noticed a few points:

1. A CursorAdapter moves the Cursor for you, take out your call to cursor.moveToNext().
2. The adapter's getView() calls newView() and bindView() on it's own; you shouldn't call these methods yourself.
3. You should watch the Android developer's lectures at Google IO to learn tips and tricks about speeding up your adapter. Tips like:
   • Using a ViewHolder, rather than calling findViewById() repeatedly.
   • Saving the indices of your Cursor, rather than calling getColumnIndex() repeatedly.
   • Fetching the LayoutInflater once and keeping a local reference.

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