Android下载管理器文件大小未正确

Question

我使用下载管理器下载文件。为了显示下载进度，我需要文件大小。当我使用以下代码时，我将文件大小设置为-1。我如何获得正确的文件大小？

DownloadManager.Query q = new DownloadManager.Query();
q.setFilterById(downloadmanagerid1);
Cursor cursor = dm.query(q);
if (cursor.moveToFirst()) {

FileDownloading.setDownload_status(cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS)));
long fileSize = cursor.getLong(cursor.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
long bytesDL = cursor.getLong(cursor.getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
Log.e("file size getting ",""+fileSize);    
FileDownloading.setDownload_progress((int) ((bytesDL * 100.0f) / fileSize));

}
else {
FileDownloading.setDownload_progress(0);
FileDownloading.setDownload_status(-1);
}
cursor.close();

Answer 1

这样做：

while ((count = input.read(data)) != -1) {
                total += count;
                // publishing the progress....
                // After this onProgressUpdate will be called
               // publishProgress("" + (int) ((total * 100) / lenghtOfFile));

                // writing data to file
                progressBar.setProgress((int) ((total * 100) / lenghtOfFile));
                output.write(data, 0, count);
            }