大图片资源下载

直接贴代码了:

package com.pocketdigi.download;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import org.apache.http.client.ClientProtocolException;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

public class JsdMain extends Activity {

 ProgressBar pb;
 TextView tv;
 int   fileSize;
 int   downLoadFileSize;
 String fileEx,fileNa,filename;
 private Button start;
 private Handler handler = new Handler()
   {
     @Override
     public void handleMessage(Message msg)
     {//定义一个Handler,用于处理下载线程与UI间通讯
       if (!Thread.currentThread().isInterrupted())
       {
         switch (msg.what)
         {
           case 0:
             pb.setMax(fileSize);
           case 1:
             pb.setProgress(downLoadFileSize);
             int result = downLoadFileSize * 100 / fileSize;
             tv.setText(result + "%");
             break;
           case 2:
             Toast.makeText(main.this, "文件下载完成", 1).show();
             break;

           case -1:
             String error = msg.getData().getString("error");
             Toast.makeText(main.this, error, 1).show();
             break;
         }
       }
       super.handleMessage(msg);
     }
   };
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        getViewById();
    }

 private void getViewById() {
  pb=(ProgressBar)findViewById(R.id.down_pb);
        tv=(TextView)findViewById(R.id.tv);
        start = (Button) this.findViewById(R.id.start);
        start.setOnClickListener(listener);
 }
   
    private OnClickListener listener = new OnClickListener() {
  @Override
  public void onClick(View v) {
   switch (v.getId()) {
   case R.id.start:
    down();
    break;
   }
  }
 };
 
 public void down(){
   new Thread(){
          public void run(){
           try {
            down_file("http://192.168.1.120:8080/test/images/IMG_0770.JPG","/sdcard/");
      //下载文件,参数:第一个URL,第二个存放路径
     } catch (ClientProtocolException e) {
      e.printStackTrace();
     } catch (IOException e) {
      e.printStackTrace();
     }
          }
         }.start();
 }
 
    public void down_file(String url,String path) throws IOException{
     //下载函数    
     filename=url.substring(url.lastIndexOf("/") + 1);
     //获取文件名
     URL myURL = new URL(url);
     URLConnection conn = myURL.openConnection();
     conn.connect();
     InputStream is = conn.getInputStream();
     this.fileSize = conn.getContentLength();//根据响应获取文件大小
     if (this.fileSize <= 0) throw new RuntimeException("无法获知文件大小 ");
     if (is == null) throw new RuntimeException("stream is null");
     FileOutputStream fos = new FileOutputStream(path+filename);
     //把数据存入路径+文件名
     byte buf[] = new byte[1024];
     downLoadFileSize = 0;
     sendMsg(0);
     do
       {
      //循环读取
         int numread = is.read(buf);
         if (numread == -1)
         {
           break;
         }
         fos.write(buf, 0, numread);
         downLoadFileSize += numread;
        
         sendMsg(1);//更新进度条
       } while (true);
     sendMsg(2);//通知下载完成
     try
       {
         is.close();
       } catch (Exception ex)
       {
         Log.e("tag", "error: " + ex.getMessage(), ex);
       }
     
    }
 private void sendMsg(int flag)
 {
     Message msg = new Message();
     msg.what = flag;
     handler.sendMessage(msg);
 } 

   
}

 

main.xml

 

<?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"
    >
 <Button
  android:id="@+id/start"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="start"
  />  
<TextView  android:id="@+id/tv"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text=""
    />
<ProgressBar android:id="@+id/down_pb"
 android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:max="100"
    style="?android:attr/progressBarStyleHorizontal"
/>
</LinearLayout>

 

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.pocketdigi.download"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".main"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>

<uses-permission android:name="android.permission.INTERNET"/>
</manifest>

posted @ 2011-05-21 09:13  移动应用开发  阅读(220)  评论(0编辑  收藏  举报