Android 下载文件 显示进度条

加入两个权限

一个是联网，另一个是读写SD卡

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

2<uses-permissionandroid:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>

下载地址是本人的另外一台主机，现在当服务器了，路径可以测试

http://210.30.12.1:8080/mp3/DJ.mp3

001import java.io.File;

002import java.io.FileNotFoundException;

003import java.io.FileOutputStream;

004import java.io.IOException;

005import java.io.InputStream;

006import java.io.OutputStream;

007import java.io.RandomAccessFile;

008import java.net.MalformedURLException;

009import java.net.URL;

010import java.net.URLConnection;

011 

012import android.app.Activity;

013import android.os.Bundle;

014import android.os.Environment;

015import android.os.Handler;

016import android.os.Message;

017import android.util.Log;

018import android.view.View;

019import android.view.View.OnClickListener;

020import android.widget.Button;

021import android.widget.ProgressBar;

022import android.widget.TextView;

023import android.widget.Toast;

024 

025public classFileDownProcessBarActivity extendsActivity {

026    /** Called when the activity is first created. */

027    privatestatic final String Path="http://210.30.12.1:8080/mp3/DJ.mp3";

028    privateProgressBar progressBar;

029    privateTextView textView;

030    privateButton button;

031    privateint FileLength;

032    privateint DownedFileLength=0;

033    privateInputStream inputStream;

034    privateURLConnection connection;

035    privateOutputStream outputStream;

036    @Override

037    publicvoid onCreate(Bundle savedInstanceState) {

038        super.onCreate(savedInstanceState);

039        setContentView(R.layout.main);

040        progressBar=(ProgressBar) findViewById(R.id.progressBar1);

041        textView=(TextView) findViewById(R.id.textView2);

042        button=(Button) findViewById(R.id.button1);

043        button.setOnClickListener(newButtonListener());

044    }

045    classButtonListener implementsOnClickListener{

046 

047        @Override

048        publicvoid onClick(View v) {

049            DownedFileLength=0;

050            // TODO Auto-generated method stub

051           Thread thread=newThread(){

052             publicvoid run(){

053                 try{

054                    DownFile(Path);

055                }catch (Exception e) {

056                    // TODO: handle exception

057                }

058             }

059           };

060           thread.start();

061        }  

062    }

063    privateHandler handler=new Handler()

064    {

065         publicvoid handleMessage(Message msg)

066        {

067        if(!Thread.currentThread().isInterrupted()) {

068            switch(msg.what) {

069            case0:

070                progressBar.setMax(FileLength);

071                Log.i("文件长度----------->", progressBar.getMax()+""); 

072                break;

073            case1:

074                progressBar.setProgress(DownedFileLength);

075                intx=DownedFileLength*100/FileLength;

076                textView.setText(x+"%");

077                break;

078            case2:

079                Toast.makeText(getApplicationContext(),"下载完成", Toast.LENGTH_LONG).show();

080                break;

081                 

082            default:

083                break;

084            }

085        }  

086        }

087          

088    };

089 

090    privatevoid DownFile(String urlString)

091    {

092         

093        /*

094         * 连接到服务器

095         */

096         

097        try {

098             URL url=new URL(urlString);

099             connection=url.openConnection();

100             if (connection.getReadTimeout()==5) {

101                Log.i("---------->", "当前网络有问题");

102                // return;

103               }

104             inputStream=connection.getInputStream();

105             

106        } catch (MalformedURLException e1) {

107            // TODO Auto-generated catch block

108            e1.printStackTrace();

109        } catch (IOException e) {

110            // TODO Auto-generated catch block

111            e.printStackTrace();

112        }

113         

114        /*

115         * 文件的保存路径和和文件名其中Nobody.mp3是在手机SD卡上要保存的路径，如果不存在则新建

116         */

117        String savePAth=Environment.getExternalStorageDirectory()+"/DownFile";

118        File file1=new File(savePAth);

119        if (!file1.exists()) {

120            file1.mkdir();

121        }

122        String savePathString=Environment.getExternalStorageDirectory()+"/DownFile/"+"DJ.mp3";

123        File file =new File(savePathString);

124        if (!file.exists()) {

125            try {

126                file.createNewFile();

127            } catch (IOException e) {

128                // TODO Auto-generated catch block

129                e.printStackTrace();

130            }  

131        }

132        /*

133         * 向SD卡中写入文件,用Handle传递线程

134         */

135        Message message=newMessage();

136        try{

137            outputStream=newFileOutputStream(file);

138            byte[] buffer=new byte[1024*4];

139            FileLength=connection.getContentLength();

140            message.what=0;

141            handler.sendMessage(message);

142            while(DownedFileLength<FileLength) {

143                outputStream.write(buffer);

144                DownedFileLength+=inputStream.read(buffer);

145                Log.i("-------->", DownedFileLength+"");

146                Message message1=newMessage();

147                message1.what=1;

148                handler.sendMessage(message1);

149            }

150            Message message2=newMessage();

151            message2.what=2;

152            handler.sendMessage(message2);

153        } catch (FileNotFoundException e) {

154            // TODO Auto-generated catch block

155            e.printStackTrace();

156        } catch (IOException e) {

157            // TODO Auto-generated catch block

158            e.printStackTrace();

159        }

160    }

161       

162}