android call log

With the following codes, the call log displayed is empty.Why is that soo??

package fypj.c;

import java.security.Provider;
import java.util.ArrayList;   
import android.app.Activity;
import android.app.ListActivity;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.CallLog;
import android.provider.ContactsContract;
import android.provider.ContactsContract.Data;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;

public class c extends ListActivity {
    private SimpleCursorAdapter myAdapter; 

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);   

    开发者_开发技巧    String[] column = new String[] {android.provider.CallLog.Calls.CACHED_NAME, android.provider.CallLog.Calls.DURATION, android.provider.CallLog.Calls.TYPE};         
        int[] names = new int[] {R.id.CLName, R.id.CLDuration, R.id.CLType};         
        myAdapter = new SimpleCursorAdapter(this,android.R.layout.simple_list_item_2, cursor, column, names);         
        setListAdapter(myAdapter);  
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <ListView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:id="@android:id/list"
    />
    <TextView  
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 

    android:id="@+id/CLName"
    />
    <TextView  
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 

    android:id="@+id/CLType"
    />
    <TextView  
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 

    android:id="@+id/CLDuration"
    />
</LinearLayout>

According to SimpleCursorAdapter,

"This constructor is deprecated. This option is discouraged, as it results in Cursor queries being performed on the application's UI thread and thus can cause poor responsiveness or even Application Not Responding errors. As an alternative, use LoaderManager with a CursorLoader. "

Try an alternative to rule out any problem with your code.