使用下载管理器下载时显示进度条

Question

我正在使用下载管理器api下载大文件，我也做到了。但问题是，下载进度的通知显示在状态栏中。但我想使用进度栏在活动中显示通知。有人做过吗？如果有，请帮帮我。

public class DownloadManagerActivity extends Activity {
private long enqueue;
private DownloadManager dm;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    BroadcastReceiver receiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if (DownloadManager.ACTION_DOWNLOAD_COMPLETE.equals(action)) {
                long downloadId = intent.getLongExtra(
                        DownloadManager.EXTRA_DOWNLOAD_ID, 0);
                Query query = new Query();
                query.setFilterById(enqueue);
                Cursor c = dm.query(query);
                if (c.moveToFirst()) {
                    int columnIndex = c
                            .getColumnIndex(DownloadManager.COLUMN_STATUS);
                    if (DownloadManager.STATUS_SUCCESSFUL == c
                            .getInt(columnIndex)) {
                        ImageView view = (ImageView) findViewById(R.id.imageView1);
                        String uriString = c
                                .getString(c
                                        .getColumnIndex(DownloadManager.COLUMN_LOCAL_URI));
                        view.setImageURI(Uri.parse(uriString));
                    }
                }
            }
        }
    };
    registerReceiver(receiver, new IntentFilter(
            DownloadManager.ACTION_DOWNLOAD_COMPLETE));
}
public void onClick(View view) {
    dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
    Request request = new Request(
            Uri.parse("http://www.vogella.de/img/lars/LarsVogelArticle7.png"));
    enqueue = dm.enqueue(request);
}

Answer 1

这是我用来在活动中显示进度条的代码，下载是由下载管理器请求的。

final ProgressDialog progressBarDialog= new ProgressDialog(this);
progressBarDialog.setTitle("Download App Data, Please Wait");
              progressBarDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
            progressBarDialog.setButton(DialogInterface.BUTTON_POSITIVE, "OK",new DialogInterface.OnClickListener(){
                public void onClick(DialogInterface dialog,
                    int whichButton){
                    // Toast.makeText(getBaseContext(),
                    //       "OK clicked!", Toast.LENGTH_SHORT).show();
                }
            });
            progressBarDialog.setProgress(0);
            new Thread(new Runnable() {
                @Override
                public void run() {
                    boolean downloading = true;
                    DownloadManager manager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);
                    while (downloading) {
                        DownloadManager.Query q = new DownloadManager.Query();
                        q.setFilterById(DownloadManagerId); //filter by id which you have receieved when reqesting download from download manager
                        Cursor cursor = manager.query(q);
                        cursor.moveToFirst();
                        int bytes_downloaded = cursor.getInt(cursor
                            .getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
                        int bytes_total = cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
                        if (cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS)) == DownloadManager.STATUS_SUCCESSFUL) {
                            downloading = false;
                }
                final int dl_progress = (int) ((bytes_downloaded * 100l) / bytes_total);
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        progressBarDialog.setProgress((int) dl_progress);
                    }
                });
                // Log.d(Constants.MAIN_VIEW_ACTIVITY, statusMessage(cursor));
                cursor.close();
            }
        }
    }).start();

  //show the dialog
        progressBarDialog.show();
          }
               }

Answer 2

我知道现在回答已经晚了。但对于那些在未来带着同样的疑问来的人，

我想nkalra0123给出的方法可能不安全。有一种叫做FileObserver的东西。

Android DownloadManager进度

上面提到的这个链接有更好的解决方案。