打开下载管理器下载的文件

Question

我正在使用DownloadManager从Web服务器下载文件。

首先，我创建DownloadManager.Request，将标题添加到其上，将数据添加到它（标题，描述，通知，MimeType），然后加入它。

之后，我等到文件完成下载，获取uri，然后创建一个打开文件的意图。

如果我想通过所选程序打开文件（PDF或TXT），我尝试与Google PDF查看器，HTML Viewer，Chrome等尝试，它总是告诉我该文件无法打开。当我想通过顶部栏DownloadManager通知打开它时，文件会正确打开。

public void getFileContent(Map<String, String> headers) {
    if (downloadManager != null) {
        DownloadManager.Request request = getRequest(headers);
        Long fileId = downloadManager.enqueue(request);
        compositeSubscription.add(RxDownloader.getInstance(getActivity())
                .download(request)
                .subscribe(path -> showFileContent(Uri.parse(path)),
                        throwable -> showError(throwable.getMessage())));
    }
}
private DownloadManager.Request getRequest(Map<String, String> headers) {
    Uri uri = Uri.parse(BuildConfig.API_URL + "api/v2/files/" + fileResource.getId() + "/raw");
    DownloadManager.Request request = new DownloadManager.Request(uri);
    request = addRequestHeaders(request, headers);
    request = setRequestData(request);
    return request;
}
private DownloadManager.Request addRequestHeaders(DownloadManager.Request request, Map<String, String> headers) {
    for (Map.Entry<String, String> entry : headers.entrySet()) {
        request.addRequestHeader(entry.getKey(), entry.getValue());
    }
    return request;
}
private DownloadManager.Request setRequestData(DownloadManager.Request request) {
    request.setTitle(getString(R.string.file_downloader));
    request.setDescription(String.format(getString(R.string.fmt_downloading), fileResource.getFileName()));
    request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
    request.setMimeType(fileResource.getMimeType());
    return request;
}
private void showFileContent(Uri uri) {
    Intent target = new Intent(Intent.ACTION_VIEW);
    target.setDataAndType(uri, fileResource.getMimeType());
    target.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
    Intent intent = Intent.createChooser(target, getString(R.string.open_file));
    try {
        startActivity(intent);
    } catch (ActivityNotFoundException e) {
        showError(getString(R.string.no_application_installed));
    }
}

Answer 1

好吧，我通过为请求设置保存目标来解决问题，因为默认下载download目标是共享卷回收系统使用的空间。https://developer.android.com/reference/android/app/downloadmanager.request.html