我正在尝试通过 DownloadManager 下载图像以显示在 Gallery 应用程序中,但我没有做任何事情。根据文档,我认为这段代码就足够了:
public void downloadImage(String url) {
Uri Download_Uri = Uri.parse(url);
DownloadManager.Request request = new DownloadManager.Request(Download_Uri);
request.allowScanningByMediaScanner();
download_id = downloadManager.enqueue(request);
}
但是当文件下载时,它不会显示在图库应用程序中。所以我尝试使用下载接收器手动添加它,如下所示:
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(downloadId);
Cursor c = downloadManager.query(query);
if (c.moveToFirst()) {
int columnIndex = c
.getColumnIndex(DownloadManager.COLUMN_STATUS);
if (DownloadManager.STATUS_SUCCESSFUL == c.getInt(columnIndex)) {
String uriString = downloadManager.getUriForDownloadedFile(download_id).toString();
//c.getString(c.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI));
Log.i("filname", uriString);
MediaScannerConnection.scanFile(ArticleActivity.this,
new String[] { uriString }, null,
new MediaScannerConnection.OnScanCompletedListener() {
public void onScanCompleted(String path, Uri uri) {
Log.i("Media Scanner", "Scanned " + path + ":");
Log.i("Media Scanner", "-> uri=" + uri);
}
});
}
}
}
}
};
那也行不通。带有“文件名”标签的 URI 类似于“content://downloads/my_downloads/97”,而不是下载的实际文件的名称。在下载应用程序中,文件名与服务器上的文件名相同。使用“Media Scanner”标签记录的 Uri 为空。
我在这里错过了一些简单的东西吗?我已经为此拉了几个小时的头发。