列表视图使用的CursorAdapter [英] Listview with 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)

david 017224860

david 017224860

david 017224860

david 017224860

david 017224860

david 017224860 .

.

.

.

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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