Android file.exists()和file.isFile不工作

Question

我尝试用以下代码下载一个文件到下载文件夹：

private fun downloadTrack(track: Track) {
        val url = track.file
        val request = DownloadManager.Request(Uri.parse(url))
        request.setDescription("Downloading track ${track.trackName}...")
        request.setTitle(track.trackName)
        request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)

        request.setDestinationInExternalPublicDir(
            Environment.DIRECTORY_DOWNLOADS,
            track.trackName + ".mp3"
        )

        val manager = getSystemService(Context.DOWNLOAD_SERVICE) as DownloadManager

        val downloadId: Long = manager.enqueue(request)
        registerBroadcast(downloadId)
    }

在下面的登录中下载了它之后，我试图检查它是否已经存在于以下代码中：

    private fun getTrack(track: Track) {
        val file =
            File(
                Environment.DIRECTORY_DOWNLOADS,
                track.trackName + ".mp3"
            )

        try {
            if (file.isFile) {
                Toast.makeText(this, "FILE EXISTS", Toast.LENGTH_SHORT).show()
            } else {
                Toast.makeText(this, "FILE NOT FOUND", Toast.LENGTH_SHORT).show()
                downloadTrack(track)
            }
        } catch (e: Exception) {
            e.printStackTrace()
        }
    }

还尝试了file.exists()并使用目录。没有任何帮助，文件被下载后就找不到了，尽管我在同一个目录中寻找它。请帮帮忙。

Answer 1

Environment.DIRECTORY_DOWNLOADS

这还不够。

你需要：

getExternalStoragePublicDirectory( Environment.DIRECTORY_DOWNLOADS)