下载一个数据库文件到app目录 [英] Download a database file to the app directory

问题描述

我想在使用 DownloadManager 单击按钮时更新应用程序的 sqlite 数据库.

i want to update the sqlite database of the app when clicking on a button using the DownloadManager.

但它说java.lang.IllegalArgumentException:不是文件 URI:/data/user/0/com.example.laudien.listviewtesting/databases/Employees"

But it says "java.lang.IllegalArgumentException: Not a file URI: /data/user/0/com.example.laudien.listviewtesting/databases/Employees"

我做错了什么?我需要许可吗?互联网权限已在清单中.

What do i make wrong? Do i need a permission for that? The internet permission is already in the manifest.

这是我的 updateDb() 方法的代码:

Here is the code of my updateDb() method:

private void updateDb() {
    DownloadManager downloadManager = (DownloadManager) getSystemService(DOWNLOAD_SERVICE); // create download manager
    DownloadFinishedReceiver receiver = new DownloadFinishedReceiver(); // create broadcast receiver
    registerReceiver(receiver, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE)); // register the receiver
    DownloadManager.Request request = new DownloadManager.Request(Uri.parse(DATABASE_URL)); // create a download request

    // delete database file if it exists
    File databaseFile = new File(getDatabasePath(DATABASE_NAME).getAbsolutePath());
    if(databaseFile.exists())
        databaseFile.delete();

    request//.setNotificationVisibility(DownloadManager.Request.VISIBILITY_HIDDEN) // not visible
        .setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI) // only via wifi
        .setDestinationUri(Uri.parse("file:" + getDatabasePath(DATABASE_NAME).getAbsolutePath())); // set path in app dir
    downloadManager.enqueue(request); // enqueue the download request
}

推荐答案

你的路径 /data/user/0/com.example.laudien.listviewtesting 是你的应用的私有内存.您使用 getFilesDir() 获得它.其他应用程序无法访问.包括下载管理器.改用 getExternalStorageDirectory() 提供的外部存储器.

Your path /data/user/0/com.example.laudien.listviewtesting is private internal memory of your app. You obtained it using getFilesDir(). Other apps have no access. Including the download manager. Use external memory given by getExternalStorageDirectory() instead.

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