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;

/**
*
*<dl>
*<dt>AppFileDownUtils.java</dt>
*<dd>Description:文件下载</dd>
*<dd>Copyright:Copyright(C)2011</dd>
*<dd>Company:</dd>
*<dd>CreateDate:2011-10-19</dd>
*</dl>
*
*@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>