我正在尝试重现 DownloadManager 在我的应用程序内的通知栏中显示的相同进度，但我的进度从未发布。我正在尝试使用 runOnUiThread() 对其进行更新，但由于某种原因尚未更新。

我的下载:

String urlDownload = "https://dl.dropbox.com/s/ex4clsfmiu142dy/test.zip?token_hash=AAGD-XcBL8C3flflkmxjbzdr7_2W_i6CZ_3rM5zQpUCYaw&dl=1";
DownloadManager.Request request = new DownloadManager.Request(Uri.parse(urlDownload));

request.setDescription("Testando");
request.setTitle("Download");
request.allowScanningByMediaScanner();
request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "teste.zip");

final DownloadManager manager = (DownloadManager) getSystemService(Context.DOWNLOAD_SERVICE);

final long downloadId = manager.enqueue(request);

final ProgressBar mProgressBar = (ProgressBar) findViewById(R.id.progressBar1);

new Thread(new Runnable() {

    @Override
    public void run() {

        boolean downloading = true;

        while (downloading) {

            DownloadManager.Query q = new DownloadManager.Query();
            q.setFilterById(downloadId);

            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 double dl_progress = (bytes_downloaded / bytes_total) * 100;

            runOnUiThread(new Runnable() {

                @Override
                public void run() {

                    mProgressBar.setProgress((int) dl_progress);

                }
            });

            Log.d(Constants.MAIN_VIEW_ACTIVITY, statusMessage(cursor));
            cursor.close();
        }

    }
}).start();

我的 statusMessage 方法:

private String statusMessage(Cursor c) {
    String msg = "???";

    switch (c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS))) {
    case DownloadManager.STATUS_FAILED:
        msg = "Download failed!";
        break;

    case DownloadManager.STATUS_PAUSED:
        msg = "Download paused!";
        break;

    case DownloadManager.STATUS_PENDING:
        msg = "Download pending!";
        break;

    case DownloadManager.STATUS_RUNNING:
        msg = "Download in progress!";
        break;

    case DownloadManager.STATUS_SUCCESSFUL:
        msg = "Download complete!";
        break;

    default:
        msg = "Download is nowhere in sight";
        break;
    }

    return (msg);
}

我的日志运行正常，而我的下载正在运行时显示“正在下载!”当它完成时“下载完成!”，但我的进度没有出现同样的情况，为什么？我真的需要一些帮助，非常感谢其他逻辑来做到这一点

最佳答案

你正在划分两个整数:

final double dl_progress = (bytes_downloaded / bytes_total) * 100;

由于 bytes_downloaded 小于 bytes_total，(bytes_downloaded/bytes_total) 将为 0，因此您的进度将始终为 0。

将您的计算更改为

final int dl_progress = (int) ((bytes_downloaded * 100l) / bytes_total);

获取整个(尽管是下限)百分位数的进度。

关于android - 使用 DownloadManager 在 Activity 中显示下载进度，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15795872/