使用下载管理器从服务器下载音频文件

Question

I am newbie in Android. I have one requirement in my application. I need to download audio files, .mp3 files from server using Downloadmanager and save it in specific folder in my device. Please help me to complete this task

Thanks in advance

Answer 1

The Android DownloadManager introduced in Android 2.3. (API 9) is a system service which allows to handle long-running HTTP downloads in the background and notify the triggering application via a broadcast receiver once the download is finished.

Courtesy: http://www.vogella.com/blog/2011/06/14/android-downloadmanager-example/

Answer 2

Please see the below code

object DownloadHelper {
    private var downloadReference: Long = 0
    private lateinit var downloadManager: DownloadManager
    var completeListener:DownloadCompleteListener?= null
    interface DownloadCompleteListener{
        fun ondownloadComplete(name:String,path:String?,uri:Uri?)
        fun ondownloadFailled(error:String)
    }


    private val receiver = object : BroadcastReceiver() {
        override fun onReceive(context: Context, intent: Intent) {
            val action = intent.action
            if (action == DownloadManager.ACTION_DOWNLOAD_COMPLETE) {
                val downloadId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1)
                if (downloadId != downloadReference) {
                    context.unregisterReceiver(this)
                    return
                }
                val query = DownloadManager.Query()
                query.setFilterById(downloadReference)
                val cursor = downloadManager.query(query)
                if(cursor != null){
                    cursor?.let {
                        if (cursor.moveToFirst()) {
                            val columnIndex = cursor.getColumnIndex(DownloadManager.COLUMN_STATUS)
                            if (DownloadManager.STATUS_SUCCESSFUL == cursor.getInt(columnIndex)) {
                                var localFile = cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI))
                                var localName = localFile.substring(localFile.lastIndexOf("/")+1)//cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_LOCAL_FILENAME))
                                completeListener!!.ondownloadComplete(localName,localFile,null)
                            } else if (DownloadManager.STATUS_FAILED == cursor.getInt(columnIndex)) {
                                completeListener!!.ondownloadFailled(cursor.getString(cursor.getColumnIndex(DownloadManager.COLUMN_REASON)))
                            }
                        }else{
                            completeListener!!.ondownloadFailled("Download cancelled or failled")
                    }
                        cursor.close()
                    }
                }else{
                    completeListener!!.ondownloadFailled("Download cancelled or failled")
                }
                context.unregisterReceiver(this)
            }
        }
    }

    fun getAudiofilePath(name:String):String{
        return Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC)
            .getAbsolutePath().toString() + "/" + name
    }

    fun downloadFile(context: Context,title: String,url: String?,uristring: Uri?, mimeType: String? = null,completeListener: DownloadCompleteListener) {
        this.completeListener = completeListener
        val guessFileName = URLUtil.guessFileName(url, null, mimeType)
        if(url == null || url.isEmpty()){
            completeListener!!.ondownloadComplete(title,url,uristring)
            return
        }
        var audiofilepath = getAudiofilePath(guessFileName);
        var applictionFile = File(audiofilepath);
        if(isAllreadyAvailabel(context,applictionFile)){
            completeListener!!.ondownloadComplete(applictionFile.name,applictionFile.absolutePath,null)
            return
        }

        downloadManager = context!!.getSystemService(Context.DOWNLOAD_SERVICE) as DownloadManager
        val downloadUri = Uri.parse(url)
        val request = DownloadManager.Request(downloadUri)
        request.apply {
            setAllowedNetworkTypes(DownloadManager.Request.NETWORK_MOBILE or DownloadManager.Request.NETWORK_WIFI)
            //setAllowedOverRoaming(true)
//            setTitle(guessFileName)
//            setDescription(guessFileName)
//            setVisibleInDownloadsUi(true)
            allowScanningByMediaScanner()
//            setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)

            //request.setDestinationUri(Uri.fromFile(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)))
            setDestinationInExternalPublicDir(Environment.DIRECTORY_MUSIC, guessFileName)

            context.registerReceiver(receiver, IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE))

            downloadReference = downloadManager.enqueue(this)
        }
    }

    fun getAllreadyDownloadAudioPath(context: Context,url:String,mimeType: String? = null):String {
        val guessFileName = URLUtil.guessFileName(url, null, mimeType)
        var audiofilepath = getAudiofilePath(guessFileName);
        var applictionFile = File(audiofilepath);
        if(isAllreadyAvailabel(context,applictionFile)){
            return applictionFile.absolutePath
        }
        return ""
    }

    fun downloadVideo(context: Context,title: String, urlFromServer: String?, mimeType: String? = null,completeListener: DownloadCompleteListener) {
        this.completeListener = completeListener
        val guessFileName = URLUtil.guessFileName(urlFromServer, null, mimeType)
        if(urlFromServer == null || urlFromServer.isEmpty()){
            completeListener!!.ondownloadComplete(title,urlFromServer, Uri.EMPTY)
            return
        }

        val directory = File(Environment.getExternalStorageDirectory().toString() + File.separator + "zingsharetemp")
        directory.mkdirs()
//        var audiofilepath = getAudiofilePath(guessFileName);
        var applicationFile = File(directory!!.path+'/'+guessFileName);
        if(isAllreadyAvailabel(context,applicationFile)){
            completeListener!!.ondownloadComplete(applicationFile.name,applicationFile.absolutePath,null)
            return
        }
        downloadManager = context!!.getSystemService(Context.DOWNLOAD_SERVICE) as DownloadManager
        val downloadUri = Uri.parse(urlFromServer)
        val request = DownloadManager.Request(downloadUri)
        request.apply {
            setAllowedNetworkTypes(DownloadManager.Request.NETWORK_MOBILE or DownloadManager.Request.NETWORK_WIFI)
            allowScanningByMediaScanner()
            setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, guessFileName)
            context.registerReceiver(receiver, IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE))
            downloadReference = downloadManager.enqueue(this)
        }
    }

    fun isAllreadyAvailabel(context: Context,applictionFile:File):Boolean{
        if(applictionFile.canRead() && applictionFile.length()>0) {
            return true
        }else{
            deleteFiles(applictionFile.absolutePath)
        }
        return false
    }
}


fun download(){

   DownloadHelper.downloadFile(context,
                title,
                url,
                uristring,
                "audio/*",
                object : DownloadHelper.DownloadCompleteListener {
                    override fun ondownloadComplete(name: String, path: String?, uristring: Uri?) {
                       
                    }

                    override fun ondownloadFailled(error: String) {
                     
                    }
                })

}

hope it will help you