android文件下载及进度条.docx

1、android 文件下载及进度条Android sdk 3.0 编译通过package com.download;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import .URL;import .URLConnection;import org.apache.http.client.ClientProtocolException;import android.app.Activity;import android.os.Bun

2、dle;import android.os.Environment;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;pu

3、blic class AndroidDownLoadActivity extends Activity private Button DownloadTextButton = null; private Button DownloadMp3Button = null; ProgressBar pb; TextView tv; int fileSize; int downLoadFileSize; String fileEx, fileNa, filename; private Handler handler = new Handler() Override public void handle

4、Message(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(AndroidDownLoad

5、Activity.this, 文件下载完成, 1) .show(); break; case -1: String error = msg.getData().getString(error); Toast.makeText(AndroidDownLoadActivity.this, error, 1) .show(); break; super.handleMessage(msg); ; /* * down load file to sdcard. */ public void down_file(String url, String path) throws IOException / 下

6、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 Log.i(value, length = + this.fileSize); if (this.fileSize

7、= 0) throw new RuntimeException(无法获知文件大小 ); if (is = null) throw new RuntimeException(stream is null); File file = new File(Environment.getExternalStorageDirectory(), filename); FileOutputStream fos = new FileOutputStream(file); / 把数据存入路径+文件名 byte buf = new byte1024; downLoadFileSize = 0; sendMsg(0)

8、; 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 = n

9、ew Message(); msg.what = flag; handler.sendMessage(msg); /* Called when the activity is first created. */ Override public void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.main); super.onCreate(savedInstanceState); setContentView(R.layout.main); pb

10、= (ProgressBar) findViewById(R.id.down_pb); tv = (TextView) findViewById(R.id.tv); new Thread() public void run() try down_file( http:/下载路径 , /sdcard/); / 下载文件，参数：第一个URL，第二个存放路径 catch (ClientProtocolException e) / TODO Auto-generated catch block e.printStackTrace(); catch (IOException e) / TODO Auto

11、-generated catch block e.printStackTrace(); .start(); DownloadTextButton = (Button) findViewById(R.id.DownTextButtonId); DownloadTextButton.setOnClickListener(new DownTextButtonListener(); DownloadMp3Button = (Button) findViewById(R.id.DownMp3ButtonId); DownloadMp3Button.setOnClickListener(new DownM

12、p3ButtonListener(); private class DownTextButtonListener implements OnClickListener public void onClick(View v) Thread thread = new Thread(new Runnable() public void run() / TODO Auto-generated method stub HttpDownloader httpDownloader = new HttpDownloader(); String irc = httpDownloader .download(ht

13、tp:/下载路径 ,); System.out.println(irc); ); thread.start(); private class DownMp3ButtonListener implements OnClickListener public void onClick(View v) Thread thread = new Thread(new Runnable() public void run() / TODO Auto-generated method stub HttpDownloader httpDownloader = new HttpDownloader(); int

14、result = httpDownloader .downFile( http:/下载路径 , test/, love.exe); System.out.println(result); ); thread.start(); package com.download;import java.io.BufferedReader;import java.io.File;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import .HttpURLConnection;imp

15、ort .MalformedURLException;import .URL;import .URLConnection;import android.util.Log;public class HttpDownloader private URL url = null; public String download(String urlStr) StringBuffer sb = new StringBuffer(); String line = null; BufferedReader buffer = null; try / 创建一个url对象 url = new URL(urlStr)

16、; / 创建一个Http连接对象 /HttpURLConnection urlConn = (HttpURLConnection) url.openConnection(); URLConnection urlConn = url.openConnection(); urlConn.connect(); int fileSize = urlConn.getContentLength();/ 根据响应获取文件大小 Log.d(filesize , * + fileSize); / 使用IO流读取数据 buffer = new BufferedReader(new InputStreamReade

17、r(urlConn .getInputStream(); while (line = buffer.readLine() != null) sb.append(line); catch (Exception e) e.printStackTrace(); finally try buffer.close(); catch (Exception e) e.printStackTrace(); return sb.toString(); public int downFile(String urlStr, String path, String fileName) InputStream inpu

18、tStream = null; try FileUtils fileUtils = new FileUtils(); if (fileUtils.isFileExist(path + fileName) return 1; else inputStream = getInputStreamFromUrl(urlStr); File resultFile = fileUtils.write2SDFromInput(path, fileName, inputStream); if (resultFile = null) return -1; catch (Exception e) e.printS

19、tackTrace(); return -1; finally try inputStream.close(); catch (Exception e) e.printStackTrace(); return 0; private InputStream getInputStreamFromUrl(String urlStr) throws MalformedURLException, IOException / TODO Auto-generated method stub url = new URL(urlStr); HttpURLConnection urlConn = (HttpURL

20、Connection) url.openConnection(); InputStream inputStream = urlConn.getInputStream(); return inputStream; package com.download;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import android.os.Environment;public cl

21、ass FileUtils private String SDPATH; public String getSDPATH() return SDPATH; public FileUtils() SDPATH = Environment.getExternalStorageDirectory() + /; public File createSDFile(String filename) throws IOException File file = new File(SDPATH + filename); file.createNewFile(); return file; public Fil

22、e createSDDir(String dirname) throws IOException File file = new File(SDPATH + dirname); file.mkdir(); return file; public boolean isFileExist(String fileName) File file = new File(SDPATH + fileName); return file.exists(); public File write2SDFromInput(String path, String fileName, InputStream input

23、) File file = null; OutputStream output = null; try createSDDir(path); file = createSDFile(path + fileName); output = new FileOutputStream(file); byte buffer = new byte4 * 1024; while (input.read(buffer) != -1) output.write(buffer); output.flush(); catch (Exception e) e.printStackTrace(); finally try output.close(); catch (Exception e) e.printStackTrace(); return file; Main.xml Manifest.xml /us