ProgressService下载图片

清单文件

<manifest xmlns:android="http://schemas.android.com/apk/res/android"          package="com.bw.alice.servicestartprogress">    <uses-permission android:name="android.permission.INTERNET"/>    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:supportsRtl="true"        android:theme="@style/AppTheme">        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN"/>                <category android:name="android.intent.category.LAUNCHER"/>            </intent-filter>        </activity>        <service android:name=".ProgressService"/>    </application></manifest>

MainActivity

import android.app.ProgressDialog;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.view.View;public class MainActivity extends AppCompatActivity {    private ProgressDialog dialog;    private ProgressReceiver receiver;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        // 注册广播        register();        // 初始化 Dialog        initDialog();    }    // 注册广播    private void register() {        receiver = new ProgressReceiver();        IntentFilter filter = new IntentFilter();        filter.addAction("com.phone.day22.progress");        registerReceiver(receiver, filter);    }    private void initDialog() {        dialog = new ProgressDialog(this);        dialog.setIcon(R.mipmap.ic_launcher);        dialog.setTitle("提示");        dialog.setMessage("图片正在下载中。。。");        dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);        dialog.setMax(100);        dialog.setIndeterminate(false);    }    public void onClick(View view) {        dialog.show();        // 开启服务        startService(new Intent(this, ProgressService.class));    }    class ProgressReceiver extends BroadcastReceiver {        @Override        public void onReceive(Context context, Intent intent) {            int progress = intent.getIntExtra("progress", 0);            // 接收下载进度 并更新dialog            dialog.setProgress(progress);            if (progress == 100) {                dialog.dismiss();            }        }    }    @Override    protected void onDestroy() {        // TODO Auto-generated method stub        super.onDestroy();        // 注销广播        unregisterReceiver(receiver);    }}

ProgressService

import android.app.Service;import android.content.Intent;import android.os.Environment;import android.os.IBinder;import java.io.BufferedInputStream;import java.io.BufferedOutputStream;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;public class ProgressService extends Service {    private String path = "http://att2.citysbs.com/suzhou/2011/12/27/09/middle_095806_kuokioik_0afeb16ab6cdd89b4d3b8cf7f0ccda32.jpg";    private String filePath = "";    private String file_name = "xrk.jpg";    private int total_lenth;    private int current;    @Override    public IBinder onBind(Intent intent) {        // TODO Auto-generated method stub        return null;    }    @Override    public void onCreate() {        super.onCreate();        // 初始化下载地址        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {            filePath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).getAbsolutePath()                    + File.separator + file_name;        }    }    @Override    public int onStartCommand(Intent intent, int flags, int startId) {        new Thread() {            public void run() {                HttpURLConnection conn = null;                BufferedInputStream inputStream = null;                BufferedOutputStream outputStream = null;                try {                    outputStream = new BufferedOutputStream(new FileOutputStream(filePath));                    URL url = new URL(path);                    conn = (HttpURLConnection) url.openConnection();                    conn.setConnectTimeout(5 * 1000);                    conn.setReadTimeout(5 * 1000);                    inputStream = new BufferedInputStream(conn.getInputStream());                    // 总长度                    total_lenth = conn.getContentLength();                    byte[] bytes = new byte[1024];                    int line;                    Intent intent = new Intent();                    // 定义一个广播                    intent.setAction("com.phone.day22.progress");                    while ((line = inputStream.read(bytes)) != -1) {                        current += line;                        outputStream.write(bytes, 0, line);                        outputStream.flush();                        int progress = (int) ((float) current / (float) total_lenth * 100);                        intent.putExtra("progress", progress);                        // 发送广播                        sendBroadcast(intent);                    }                } catch (MalformedURLException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                } catch (IOException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                } finally {                    if (inputStream != null) {                        try {                            inputStream.close();                        } catch (IOException e) {                            // TODO Auto-generated catch block                            e.printStackTrace();                        }                    }                    if (outputStream != null) {                        try {                            outputStream.close();                        } catch (IOException e) {                            // TODO Auto-generated catch block                            e.printStackTrace();                        }                    }                    if (conn != null) {                        conn.disconnect();                    }                }            };        }.start();        return super.onStartCommand(intent, flags, startId);    }    @Override    public void onDestroy() {        // TODO Auto-generated method stub        super.onDestroy();    }}

activity_main

<RelativeLayout    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context="com.bw.alice.servicestartprogress.MainActivity">    <Button        android:id="@+id/button1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentLeft="true"        android:layout_alignParentTop="true"        android:layout_marginTop="18dp"        android:onClick="onClick"        android:text="开始下载" /></RelativeLayout>