游戏开发4_01 数据存储--sqlite 2

package wyf.wpf; //声明包语句
import android.app.Activity; //引入相关类
import android.content.ContentResolver; //引入相关类
import android.database.Cursor; //引入相关类
import android.net.Uri; //引入相关类
import android.os.Bundle; //引入相关类
import android.provider.Contacts.People; //引入相关类
import android.widget.TextView; //引入相关类
//继承自Activity的子类
public class Sample_4_4 extends Activity {
String [] columns = { //查询Content Provider时希望返回的列
People._ID,
People.NAME,
};
Uri contactUri = People.CONTENT_URI; //访问Content Provider需要的Uri
TextView tv; //TextView对象引用
    @Override
    public void onCreate(Bundle savedInstanceState) { //重写onCreate方法
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        tv = (TextView)findViewById(R.id.tv);        //获得TextView对象引用
        String result = getQueryData(); //调用方法访问Content Provider
        tv.setText("ID\t名字\n"+result); //将查询到的信息显示到TextView中
    }
    //方法：获取联系人列表信息，返回String对象
    public String getQueryData(){
    String result = "";
    ContentResolver resolver = getContentResolver(); //获取ContentResolver对象
    Cursor cursor = resolver.query(contactUri, columns, null, null, null); //调用方法查询Content Provider
        int idIndex = cursor.getColumnIndex(People._ID); //获得_ID字段的列索引
        int nameIndex = cursor.getColumnIndex(People.NAME); //获得NAME字段的列索引
        for(cursor.moveToFirst();(!cursor.isAfterLast());cursor.moveToNext()){ //遍历Cursor，提取数据
        result = result + cursor.getString(idIndex)+ "\t";
        result = result + cursor.getString(nameIndex)+ "\t\n";
        }
        cursor.close(); //关闭Cursor对象
        return result;
    }   
}






/*

package wyf.wpf;

import android.app.Activity;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.Contacts.People;
import android.widget.TextView;

public class Sample_4_4 extends Activity {
String [] columns = {
People._ID,
People.NAME,
People.NUMBER
};
Uri contactUri = People.CONTENT_URI;
TextView tv; //TextView对象引用
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        tv = (TextView)findViewById(R.id.tv);       
        tv.setText(getQueryData());
    }
    //方法：获取联系人列表信息，返回String对象
    public String getQueryData(){
    String result = "";
    Cursor cursor = this.managedQuery(contactUri, columns, null, null, null);
        System.out.println("=========  the size of cursor is:"+cursor.getCount());
        int idIndex = cursor.getColumnIndex(People._ID);
        int nameIndex = cursor.getColumnIndex(People.NAME);
        int numberIndex = cursor.getColumnIndex(People.NUMBER);
        for(cursor.moveToFirst();(!cursor.isAfterLast());cursor.moveToNext()){ //遍历Cursor，提取数据
        result = result + cursor.getString(idIndex)+ "\t";
        result = result + cursor.getString(nameIndex)+ "\t";
        result = result + cursor.getString(numberIndex)+ "\t\n";       
        }
        cursor.close();
    return result;
    }   
}


*/