android - 如何获取下载状态？

Question

我使用 DownloadManager 来获取下载状态，但它仍然无法正常工作，它永远不会跳转到条件if(c.moveToFirst())，我不知道为什么。有人可以帮我吗？

private final BroadcastReceiver myReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();

            if(Intent.ACTION_SCREEN_OFF.equals(action)) {

                DownloadManager downloadMgr = (DownloadManager)getSystemService(DOWNLOAD_SERVICE);
                DownloadManager.Query query = new DownloadManager.Query();
                query.setFilterByStatus(DownloadManager.STATUS_FAILED|DownloadManager.STATUS_PENDING|DownloadManager.STATUS_RUNNING|DownloadManager.STATUS_SUCCESSFUL);
                Cursor c = downloadMgr.query(query);
                if(c==null) {
                    //
                }
                else {
                    if(c.moveToFirst()) {
                        int columnIndex = c.getColumnIndex(DownloadManager.COLUMN_STATUS);
                        int status = c.getInt(columnIndex);
                        if(status == DownloadManager.STATUS_RUNNING){
                        //do something
                        }
                    }
                }
            }
        }
    };

Answer 1

这里有几个链接参考它。

• 链接1
• 链接2

示例代码如下::

DownloadManager.Query query = null;
    Cursor c = null;
    DownloadManager downloadManager = null;
    downloadManager = (DownloadManager)getSystemService(Context.DOWNLOAD_SERVICE);
    query = new DownloadManager.Query();
     if(query!=null) {
                query.setFilterByStatus(DownloadManager.STATUS_FAILED|DownloadManager.STATUS_PAUSED|DownloadManager.STATUS_SUCCESSFUL|
                        DownloadManager.STATUS_RUNNING|DownloadManager.STATUS_PENDING);
            } else {
                return;
            }
    c = downloadManager.query(query);
    if(c.moveToFirst()) { 
    int status = c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS)); 
    switch(status) { 
    case DownloadManager.STATUS_PAUSED: 
    break; 
    case DownloadManager.STATUS_PENDING: 
    break; 
    case DownloadManager.STATUS_RUNNING: 
    break; 
    case DownloadManager.STATUS_SUCCESSFUL: 
    break; 
    case DownloadManager.STATUS_FAILED: 
    break; 
    }
}

Answer 2

我就是这样做的

//broadcastReceiver
private val receiver = object : BroadcastReceiver() {
    override fun onReceive(context: Context, intent: Intent) {
        val id = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1)

      
        //call notify off NotificationManager passing in the id & notification
        notificationManager.apply {

            notify(NOTIFICATION_ID, createNotification())
        }


        //DownloadManager.Query() is used to filter DownloadManager queries
        val query = DownloadManager.Query()

        query.setFilterById(id)

        val cursor = downloadManager.query(query)

        if (cursor.moveToFirst()){
val status = cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS))

            when (status) {
                DownloadManager.STATUS_SUCCESSFUL ->{


                }
                DownloadManager.STATUS_FAILED -> {
                    
                }

            }
        }

    }
}