子線程加載數據

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;

/**
 * 	通過子線程加載數據
 * 		數據是在手機的內存中
 *
 */
public class MainActivity extends FragmentActivity {
	private String url = "content://com.mma/student/";// url
	private ListView listview;
	private EditText ee;
	private ContentResolver resolver;// 客戶端(訪問服務端)
	private SimpleCursorAdapter adapter;// 適配器(數據庫專用)
	private Cursor cursor;// 遊標
	private LoaderManager manager;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		listview = (ListView) findViewById(R.id.listview);// 視圖列表
		ee=(EditText) findViewById(R.id.ee);
		
		manager=getSupportLoaderManager();//創建LoaderManager對象
		
		adapter=new SimpleCursorAdapter(MainActivity.this,//創建適配器
				android.R.layout.simple_list_item_2,
				null,//遊標這裏先爲空
				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());//重啓Loader
	}
	
	
	
	
	class MyLoader implements LoaderManager.LoaderCallbacks<Cursor>{

		@Override//回調時會調用該方法
		public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
			CursorLoader loader=null;//定義CursorLoader
			if(arg1==null){//編輯框沒有輸入時
			 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//上個方法返回值不爲null時，會調用該方法
		public void onLoadFinished(Loader<Cursor> arg0, Cursor arg1) {
			adapter.swapCursor(arg1);
		}

		@Override//退出活動時，會調用該方法
		public void onLoaderReset(Loader<Cursor> arg0) {
			adapter.swapCursor(null);
		}
		
		
	}
	
	
	
	
	
	
	
	
	
	
	
	
	
	

}