合肥做企业网站/广东今日最新疫情通报

1、DownLoadManager是Android用系统服务(Service)的方式来优化处理长时间的下载操作的一个工具类。避免了我们去处理多线程，通知栏等等。

2、不要忘记添加权限

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

3、

public class MainActivity extends Activity {private DownloadManager downloadManager;private long downloadId;private TextView mTvMsg;private String downId;private String title;private String address;private String size;private String sizeTotal;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);initView();initData();}private void initView(){mTvMsg = (TextView) findViewById(R.id.tv_msg);}private void initData(){downloadManager = (DownloadManager)getSystemService(DOWNLOAD_SERVICE);String apkUrl = "http://img.meilishuo.net/css/images/AndroidShare/Meilishuo_3.6.1_10006.apk";DownloadManager.Request request = new DownloadManager.Request(Uri.parse(apkUrl));// 设置下载地址为sd卡的Trinea文件夹，文件名为MeiLiShuo.apkrequest.setDestinationInExternalPublicDir("aaaa", "MeiLiShuo.apk");// 表示允许MediaScanner扫描到这个文件，默认不允许
        request.allowScanningByMediaScanner();// 设置下载中通知栏提示的标题request.setTitle("MeiLiShuo");// 设置下载中通知栏提示的介绍request.setDescription("美丽说");// 默认只显示下载中通知。VISIBILITY_VISIBLE_NOTIFY_COMPLETED表示下载完成后显示通知栏提示。VISIBILITY_HIDDEN表示不显示任何通知栏提示，// 这个需要在AndroidMainfest中添加权限android.permission.DOWNLOAD_WITHOUT_NOTIFICATION
        request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);// 设置下载文件的mineType。因为下载管理Ui中点击某个已下载完成文件及下载完成点击通知栏提示都会根据mimeType去打开文件，// 所以我们可以利用这个属性用于响应点击的打开文件request.setMimeType("application/cn.trinea.download.file");// 添加请求下载的网络链接的http头，比如User-Agent，gzip压缩等// request.addRequestHeader(String header, String value)
        downloadId = downloadManager.enqueue(request);new Thread(thread).start();}/** 查询下载任务信息*/private void queryDownTask(DownloadManager downManager,long id) {DownloadManager.Query query = new DownloadManager.Query();query.setFilterById(id);Cursor cursor= downManager.query(query);while(cursor.moveToNext()){downId= cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_ID));title = cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_TITLE));address = cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI));//String statuss = cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS));size= cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));sizeTotal = cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));}cursor.close();}private Thread thread = new Thread(){public void run() {while (true) {queryDownTask(downloadManager, downloadId);try {sleep(1000);} catch (InterruptedException e) {// TODO Auto-generated catch block
                    e.printStackTrace();}handler.sendEmptyMessage(0);}};};private Handler handler = new Handler(){public void handleMessage(android.os.Message msg) {if(msg.what == 0){mTvMsg.setText(downId + "\n" + title + "\n" + address + "\n" + size + "\n" + sizeTotal);}};};
}

4、下载成功后系统会发出广播DownloadManager.ACTION_DOWNLOAD_COMPLETE，并传递并传递downloadId作为参数。我们可以监听广播来进行下载后的操作。

<!-- 注册系统静态广播接收器 -->  <receiver android:name=".DownloadReceive">  <intent-filter>  <action android:name="android.intent.action.DOWNLOAD_COMPLETE" /></intent-filter>  </receiver>

public class DownloadReceive extends BroadcastReceiver {@Overridepublic void onReceive(Context context, Intent intent) {// TODO Auto-generated method stublong reference = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1); Toast.makeText(context, reference + "", Toast.LENGTH_SHORT).show();}}

5、有了通知栏其实下载进度可以不用监听的，不过我们还是可以通过DownManager.Query和Cursor查询下载信息。

6、参考博文：http://www.open-open.com/lib/view/open1428024407365.html