检测系统何时开始下载

Question

有没有办法检测系统何时开始下载并获取其信息并强制将其下载到特定位置？我用谷歌搜索了一下，结果没有多大帮助

Answer 1

启动此服务类，然后开始下载，它将打印下载状态的结果。

公共类 MyService 扩展服务 {

private Timer timer;
private TimerTask timerTask;
private static final int SAMPLING_RATE = 1000;
public MyService() {
}
@Override
public IBinder onBind(Intent intent) {
    return null;
}
@Override
@Deprecated
public void onStart(Intent intent, int startId) {
    Log.e("Download", "onstart");
}
@Override
public void onCreate() {
    timer = new Timer();
    timerTask = new TimerTask() {
        @Override
        public void run() {
            // Log.d(MyService.class.toString(),
            // "tic ... "+System.currentTimeMillis());
            getDownloadData();
        }
    };
    if (timer != null && timerTask != null) {
        timer.schedule(timerTask, 0, SAMPLING_RATE);
    }
}
@TargetApi(Build.VERSION_CODES.GINGERBREAD)
@SuppressLint("NewApi")
public void getDownloadData() {
    DownloadManager downloadMgr = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
    DownloadManager.Query query = new DownloadManager.Query();
    query.setFilterByStatus(DownloadManager.STATUS_FAILED
            | DownloadManager.STATUS_PENDING
            | DownloadManager.STATUS_RUNNING
            | DownloadManager.STATUS_SUCCESSFUL);
    Cursor c = downloadMgr.query(query);
    if (c == null) {
        System.out.println("--------------------------");
    } else {
        if (c.moveToFirst()) {
            System.out.println("------------End--------------");
            while (c.isAfterLast() == false) {
                getStatus(c);
                c.moveToNext();
            }
        }
    }
}
public void getStatus(Cursor c) {
    int columnIndex = c.getColumnIndex(DownloadManager.COLUMN_STATUS);
    int columnReason = c.getColumnIndex(DownloadManager.COLUMN_REASON);
    int reason = c.getInt(columnReason);
    int status = c.getInt(columnIndex);
    String statusText = null;
    String reasonText = null;
    switch (status) {
    case DownloadManager.STATUS_FAILED:
        statusText = "STATUS_FAILED";
        switch (reason) {
        case DownloadManager.ERROR_CANNOT_RESUME:
            reasonText = "ERROR_CANNOT_RESUME";
            break;
        case DownloadManager.ERROR_DEVICE_NOT_FOUND:
            reasonText = "ERROR_DEVICE_NOT_FOUND";
            break;
        case DownloadManager.ERROR_FILE_ALREADY_EXISTS:
            reasonText = "ERROR_FILE_ALREADY_EXISTS";
            break;
        case DownloadManager.ERROR_FILE_ERROR:
            reasonText = "ERROR_FILE_ERROR";
            break;
        case DownloadManager.ERROR_HTTP_DATA_ERROR:
            reasonText = "ERROR_HTTP_DATA_ERROR";
            break;
        case DownloadManager.ERROR_INSUFFICIENT_SPACE:
            reasonText = "ERROR_INSUFFICIENT_SPACE";
            break;
        case DownloadManager.ERROR_TOO_MANY_REDIRECTS:
            reasonText = "ERROR_TOO_MANY_REDIRECTS";
            break;
        case DownloadManager.ERROR_UNHANDLED_HTTP_CODE:
            reasonText = "ERROR_UNHANDLED_HTTP_CODE";
            break;
        case DownloadManager.ERROR_UNKNOWN:
            reasonText = "ERROR_UNKNOWN";
            break;
        }
        break;
    case DownloadManager.STATUS_PAUSED:
        statusText = "STATUS_PAUSED";
        switch (reason) {
        case DownloadManager.PAUSED_QUEUED_FOR_WIFI:
            reasonText = "PAUSED_QUEUED_FOR_WIFI";
            break;
        case DownloadManager.PAUSED_UNKNOWN:
            reasonText = "PAUSED_UNKNOWN";
            break;
        case DownloadManager.PAUSED_WAITING_FOR_NETWORK:
            reasonText = "PAUSED_WAITING_FOR_NETWORK";
            break;
        case DownloadManager.PAUSED_WAITING_TO_RETRY:
            reasonText = "PAUSED_WAITING_TO_RETRY";
            break;
        }
        break;
    case DownloadManager.STATUS_PENDING:
        statusText = "STATUS_PENDING";
        break;
    case DownloadManager.STATUS_RUNNING:
        statusText = "STATUS_RUNNING";
        break;
    case DownloadManager.STATUS_SUCCESSFUL:
        statusText = "STATUS_SUCCESSFUL";
        break;
    }
    Log.d("status", statusText + "   " + reasonText);
}

}