子线程加载数据

package com.example.a05273;

import java.io.File;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.DialogInterface;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.LoaderManager;
import android.support.v4.app.LoaderManager.LoaderCallbacks;
import android.support.v4.content.CursorLoader;
import android.support.v4.content.Loader;
import android.support.v4.widget.SimpleCursorAdapter;
import android.view.View;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;

/**
* 	通过子线程加载数据
* 		数据是在手机的内存中
*
*/
public class MainActivity extends FragmentActivity {
private String url = "content://com.mma/student/";// url
private ListView listview;
private EditText ee;
private ContentResolver resolver;// 客户端(访问服务端)
private SimpleCursorAdapter adapter;// 适配器(数据库专用)
private Cursor cursor;// 游标
private LoaderManager manager;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listview = (ListView) findViewById(R.id.listview);// 视图列表
ee=(EditText) findViewById(R.id.ee);

manager=getSupportLoaderManager();//创建LoaderManager对象

adapter=new SimpleCursorAdapter(MainActivity.this,//创建适配器
android.R.layout.simple_list_item_2,
null,//游标这里先为空
new String[]{"name","age"},
new int[]{android.R.id.text1,android.R.id.text2},
0);

listview.setAdapter(adapter);

manager.initLoader(1, null, new MyLoader());//初始化Loader

}

public void mma(View view){
String name=ee.getText().toString();
Bundle bundle=new Bundle();
bundle.putString("name", name);

manager.restartLoader(1, bundle, new MyLoader());//重启Loader
}

class MyLoader implements LoaderManager.LoaderCallbacks<Cursor>{

@Override//回调时会调用该方法
public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
CursorLoader loader=null;//定义CursorLoader
if(arg1==null){//编辑框没有输入时
loader=new CursorLoader(MainActivity.this,
Uri.parse(url),
null,
null,
null,
null);
}else{
String name=arg1.getString("name");
loader=new CursorLoader(MainActivity.this,
Uri.parse(url),
null,
"name like ?",
new String[]{name+"%"} , //模糊查找
null);
}

return loader;
}

@Override//上个方法返回值不为null时，会调用该方法
public void onLoadFinished(Loader<Cursor> arg0, Cursor arg1) {
adapter.swapCursor(arg1);
}

@Override//退出活动时，会调用该方法
public void onLoaderReset(Loader<Cursor> arg0) {
adapter.swapCursor(null);
}

}

}