使用SQLite缓存数据(缓存文本和大图片)例子源码下载

【实例简介】

    使用SQLite缓存数据,缓存 大图片 小图片 文字 等信息

【实例截图】

【核心代码】

package com.cache.sqlite;

//import java.io.OutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

//import com.cache.file.MySQLiteDemo.OnClickListenerImpl2;
//import com.cache.file.MySQLiteDemo.OnClickListenerImpl3;
import com.cache.sqlite.R;

import android.app.Activity;
import android.content.Intent;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Bundle;
import android.os.Environment;
import android.text.method.ScrollingMovementMethod;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;

public class MySQLiteDemo extends Activity {
	private Button findBut = null ;
	private Button updateBut = null ;
	private TextView textView = null;
	private SQLiteOpenHelper helper = null ;
	private LinearLayout mylayout = null ;
	//private ListView listView = null;
	private Button showSmallImageBut = null;
	private Button showLargeImageBut = null;
	
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		super.setContentView(R.layout.main);
		this.findBut = (Button) super.findViewById(R.id.findBut) ;
		this.updateBut = (Button) super.findViewById(R.id.updateBut) ;
		this.mylayout = (LinearLayout) super.findViewById(R.id.mylayout) ;
		this.findBut.setOnClickListener(new OnClickListenerImpl()) ;
		this.updateBut.setOnClickListener(new OnClickListenerImpl1()) ;
		this.showSmallImageBut = (Button) super.findViewById(R.id.smallImageBut);
		this.showSmallImageBut.setOnClickListener(new OnClickListenerImpl2());
		this.showLargeImageBut = (Button) super.findViewById(R.id.largeImageBut);
		this.showLargeImageBut.setOnClickListener(new OnClickListenerImpl3());
		this.helper = new MyDatabaseHelper(this);
		this.textView = (TextView)this.findViewById(R.id.textview);
		this.textView.setMovementMethod(ScrollingMovementMethod.getInstance());
		helper.getWritableDatabase();
		//this.helper.getReadableDatabase();
		
	}
	private class OnClickListenerImpl implements OnClickListener{
		//查询全部的数据
		@Override
		public void onClick(View v) {
			MytabCursor mtc = new MytabCursor(MySQLiteDemo.this.helper.getReadableDatabase());
			List<WebContent> all = mtc.find();
			System.out.println("the size of all is " all.size());
//			ArrayAdapter<String> adapter = new ArrayAdapter<String>(
//					MySQLiteDemo.this, //上下文对象
//					R.layout.list_item1);
			Iterator<WebContent> iter = all.iterator() ;
			String text = new String("缓存信息：\n");
			while(iter.hasNext()){
				WebContent wc = iter.next() ;
				text  = "ID: "   wc.getID()   "\n";
				text  = "DepCode: "   wc.getDepCode()   "\n";
				text  = "WorkGroupCode: "   wc.getWorkGroupCode()   "\n";
				text  = "WODate: "   wc.getWODate()   "\n";
				text  = "WorkShiftCode: "   wc.getWorkShiftCode()   "\n";
				text  = "WOSN: "   wc.getWOSN()   "\n";
				text  = "WOHeadTaskCount: "   wc.getWOHeadTaskCount()   "\n";
				
			}
			MySQLiteDemo.this.textView.setText(text);
		}
		
	}
	private class OnClickListenerImpl1 implements OnClickListener{
		//更新数据
		@Override
		public void onClick(View v) {
			//MySQLiteDemo.this.helper = new MyDatabaseHelper(MySQLiteDemo.this);
			List<WebContent> all = new ArrayList<WebContent>();
			//OutputStream output = null;
			GetWebContent gwc = new GetWebContent();
			try {
				all = gwc.GetWebContentList();
				if(all == null){
					return;
				}
			} catch (Exception e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
			new MytabTransaction(MySQLiteDemo.this.helper.getReadableDatabase(), all).updateBatch() ;
		}
		
	}
	private class OnClickListenerImpl2 implements OnClickListener {
		// 显示小图片
		@Override
		public void onClick(View v) {
			MytabCursor mtc = new MytabCursor(MySQLiteDemo.this.helper.getReadableDatabase());
			List<WebContent> all = mtc.find();
			//System.out.println("the size of all is " all.size());
			Iterator<WebContent> iter = all.iterator() ;
			byte[] smallImageData;
			if(iter.hasNext()){
				WebContent wc = iter.next();
				smallImageData = wc.getSmallImageStream();
				System.out.println("the size of smallImageData is "   smallImageData.length);
				try {
					Intent it = new Intent(MySQLiteDemo.this, ShowSmallImage.class);
					it.putExtra("smallImageData", smallImageData) ;
					MySQLiteDemo.this.startActivity(it) ;	// 跳转
				} catch (Exception e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
			
			
			
		}

	}
	private class OnClickListenerImpl3 implements OnClickListener {
		// 显示大图片
		@Override
		public void onClick(View v) {
			MytabCursor mtc = new MytabCursor(MySQLiteDemo.this.helper.getReadableDatabase());
			List<WebContent> all = mtc.find();
			Iterator<WebContent> iter = all.iterator() ;
			String largeImageUrl = new String();
			if(iter.hasNext()){
				largeImageUrl = iter.next().getLargeImageUrl();
				try {
					Intent it = new Intent(MySQLiteDemo.this, ShowLargeImage.class);
					it.putExtra("largeImageData", largeImageUrl) ;
					MySQLiteDemo.this.startActivity(it) ;	// 跳转
					
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		}

	}
}