Android开发之文件下载，状态时显示下载进度，点击自动安装

在进行软件升级时，需要进行文件下载，在这里实现自定义的文件下载，并在状态栏显示下载进度，下载完成后，点击触发安装。

效果如图：

用于下载文件和显示现在进度的线程类如下：

 packagecom.channelsoft.ahzyfis.util;

 importjava.io.File;
 importjava.io.FileOutputStream;
 importjava.io.InputStream;
 importjava.net.HttpURLConnection;
 importjava.net.URL;

 importandroid.app.Notification;
 importandroid.app.NotificationManager;
 importandroid.app.PendingIntent;
 importandroid.content.Context;
 importandroid.content.Intent;
 importandroid.net.Uri;
 importandroid.os.Environment;
 importandroid.os.Handler;
 importandroid.os.Message;
 importandroid.util.Log;
 importandroid.widget.RemoteViews;
 importandroid.widget.Toast;

 importcom.channelsoft.ahzyfis.AhzyFisActivity;
 importcom.channelsoft.ahzyfis.R;

 /**
 *
 *
 *AppFileDownUtils.java
 *Description:文件下载
 *Copyright:Copyright(C)2011
 *Company:
 *CreateDate:2011-10-19
 *
 *
 *@authorZhanHua
 */
 publicclassAppFileDownUtilsextendsThread{

 privateContextmContext;
 privateHandlermHandler;
 privateStringmDownloadUrl;//文件下载url，已做非空检查
 privateStringmFileName;
 privateMessagemsg;

 privatefinalStringAPP_FOLDER="DownDemo";//sd卡应用目录
 privatefinalStringAPK_FOLDER="apkFile";//下载apk文件目录

 publicstaticfinalintMSG_UNDOWN=0;//未开始下载
 publicstaticfinalintMSG_DOWNING=1;//下载中
 publicstaticfinalintMSG_FINISH=1;//下载完成
 publicstaticfinalintMSG_FAILURE=2;//下载失败

 privateNotificationManagermNotifManager;
 privateNotificationmDownNotification;
 privateRemoteViewsmContentView;//下载进度View
 privatePendingIntentmDownPendingIntent;

 publicAppFileDownUtils(Contextcontext,Handlerhandler,
 StringdownloadUrl,StringfileName){
 mContext=context;
 mHandler=handler;
 mDownloadUrl=downloadUrl;
 mFileName=fileName;
 mNotifManager=(NotificationManager)mContext
 .getSystemService(Context.NOTIFICATION_SERVICE);
 msg=newMessage();
 }

 @Override
 publicvoidrun(){
 try{
 if(Environment.getExternalStorageState().equals(
 Environment.MEDIA_MOUNTED)){
 MessagedowningMsg=newMessage();
 downingMsg.what=MSG_DOWNING;
 mHandler.sendMessage(downingMsg);
 //SD卡准备好
 FilesdcardDir=Environment.getExternalStorageDirectory();
 //文件存放路径：sdcard/DownDemo/apkFile
 Filefolder=newFile(sdcardDir+File.separator+APP_FOLDER
 +File.separator+APK_FOLDER);
 if(!folder.exists()){
 //创建存放目录
 folder.mkdir();
 }
 FilesaveFilePath=newFile(folder,mFileName);
 System.out.println(saveFilePath);
 mDownNotification=newNotification(
 android.R.drawable.stat_sys_download,mContext
 .getString(R.string.notif_down_file),System
 .currentTimeMillis());
 mDownNotification.flags=Notification.FLAG_ONGOING_EVENT;
 mDownNotification.flags=Notification.FLAG_AUTO_CANCEL;
 mContentView=newRemoteViews(mContext.getPackageName(),
 R.layout.custom_notification);
 mContentView.setImageViewResource(R.id.downLoadIcon,
 android.R.drawable.stat_sys_download);
 mDownPendingIntent=PendingIntent.getActivity(mContext,0,newIntent(),0);
 booleandownSuc=downloadFile(mDownloadUrl,saveFilePath);
 if(downSuc){
 msg.what=MSG_FINISH;
 Notificationnotification=newNotification(
 android.R.drawable.stat_sys_download_done,mContext
 .getString(R.string.downloadSuccess),
 System.currentTimeMillis());
 notification.flags=Notification.FLAG_ONGOING_EVENT;
 notification.flags=Notification.FLAG_AUTO_CANCEL;
 Intentintent=newIntent(Intent.ACTION_VIEW);
 intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
 intent.setDataAndType(Uri.fromFile(saveFilePath),
 "application/vnd.android.package-archive");
 PendingIntentcontentIntent=PendingIntent.getActivity(
 mContext,0,intent,0);
 notification.setLatestEventInfo(mContext,mContext
 .getString(R.string.downloadSuccess),null,
 contentIntent);
 mNotifManager.notify(R.drawable.icon,notification);
 }else{
 msg.what=MSG_FAILURE;
 Notificationnotification=newNotification(
 android.R.drawable.stat_sys_download_done,mContext
 .getString(R.string.downloadFailure),
 System.currentTimeMillis());
 notification.flags=Notification.FLAG_AUTO_CANCEL;
 PendingIntentcontentIntent=PendingIntent.getActivity(
 mContext,0,newIntent(),0);
 notification.setLatestEventInfo(mContext,mContext
 .getString(R.string.downloadFailure),null,
 contentIntent);
 mNotifManager.notify(R.drawable.icon,notification);
 }

 }else{
 Toast.makeText(mContext,Environment.getExternalStorageState(),
 Toast.LENGTH_SHORT).show();
 msg.what=MSG_FAILURE;
 }
 }catch(Exceptione){
 Log.e(AhzyFisActivity.TAG,"AppFileDownUtilscatchException:",e);
 msg.what=MSG_FAILURE;
 }finally{
 mHandler.sendMessage(msg);
 }
 }

 /**
 *
 *Desc:文件下载
 *
 *@paramdownloadUrl
 *下载URL
 *@paramsaveFilePath
 *保存文件路径
 *@returnture:下载成功false:下载失败
 */
 publicbooleandownloadFile(StringdownloadUrl,FilesaveFilePath){
 intfileSize=-1;
 intdownFileSize=0;
 booleanresult=false;
 intprogress=0;
 try{
 URLurl=newURL(downloadUrl);
 HttpURLConnectionconn=(HttpURLConnection)url.openConnection();
 if(null==conn){
 returnfalse;
 }
 //读取超时时间毫秒级
 conn.setReadTimeout(10000);
 conn.setRequestMethod("GET");
 conn.setDoInput(true);
 conn.connect();
 if(conn.getResponseCode()==HttpURLConnection.HTTP_OK){
 fileSize=conn.getContentLength();
 InputStreamis=conn.getInputStream();
 FileOutputStreamfos=newFileOutputStream(saveFilePath);
 byte[]buffer=newbyte[1024];
 inti=0;
 inttempProgress=-1;
 while((i=is.read(buffer))!=-1){
 downFileSize=downFileSize+i;
 //下载进度
 progress=(int)(downFileSize*100.0/fileSize);
 fos.write(buffer,0,i);

 synchronized(this){
 if(downFileSize==fileSize){
 //下载完成
 mNotifManager.cancel(R.id.downLoadIcon);
 }elseif(tempProgress!=progress){
 //下载进度发生改变，则发送Message
 mContentView.setTextViewText(R.id.progressPercent,
 progress+"%");
 mContentView.setProgressBar(R.id.downLoadProgress,
 100,progress,false);
 mDownNotification.contentView=mContentView;
 mDownNotification.contentIntent=mDownPendingIntent;
 mNotifManager.notify(R.id.downLoadIcon,
 mDownNotification);
 tempProgress=progress;
 }
 }
 }
 fos.flush();
 fos.close();
 is.close();
 result=true;
 }else{
 result=false;
 }
 }catch(Exceptione){
 result=false;
 Log.e(AhzyFisActivity.TAG,"downloadFilecatchException:",e);
 }
 returnresult;
 }
 }

在下载过程中，如果需要和主线程（UI Main Thread）通信，及时让主线程了解下载进度和状态，可用通过Handle向主线程发送Message

进度条显示的布局文件如下：

 xmlversion="1.0"encoding="utf-8"?>
 <LinearLayout
 android:id="@+id/custom_notification"
 xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="horizontal"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent">
 <ImageView
 android:id="@+id/downLoadIcon"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_marginLeft="5dip"
 android:layout_gravity="center_vertical"
 />
 <TextView
 android:layout_height="fill_parent"
 android:layout_width="wrap_content"
 android:layout_marginLeft="5dip"
 android:text="@string/downloadProgress"
 android:gravity="center_vertical"
 />
 <ProgressBar
 android:id="@+id/downLoadProgress"
 style="?android:attr/progressBarStyleHorizontal"
 mce_style="?android:attr/progressBarStyleHorizontal"
 android:layout_marginLeft="10dip"
 android:layout_width="150dip"
 android:layout_height="wrap_content"
 android:layout_gravity="center_vertical"
 />
 <TextView
 android:id="@+id/progressPercent"
 android:layout_height="fill_parent"
 android:layout_width="wrap_content"
 android:layout_marginLeft="5dip"
 android:gravity="center_vertical"
 />
 LinearLayout>