DownloadManager.java

    @Override
    public void onResume(){
        super.onResume();
        IntentFilter completeFilter = new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE);
        registerReceiver(completeReceiver, completeFilter);
    }

    @Override
    public void onPause(){
        super.onPause();
        unregisterReceiver(completeReceiver);
    }

    private final BroadcastReceiver completeReceiver = new BroadcastReceiver(){
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if (DownloadManager.ACTION_DOWNLOAD_COMPLETE.equals(action)) {
                long downloadId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, 0);
                if (downloadId == mDownloadingId) {
                    Query query = new Query();
                    query.setFilterById(mDownloadingId);
                    Cursor c = mDownloadManager.query(query);
                    if (c.moveToFirst()) {
                        int columnIndex = c.getColumnIndex(DownloadManager.COLUMN_STATUS);
                        if (DownloadManager.STATUS_SUCCESSFUL == c.getInt(columnIndex)) {
                            //String uriString = c.getString(c.getColumnIndex(DownloadManager.COLUMN_LOCAL_URI));
                            mDownloadingId = 0;
                            mDownloadManager = null;
                            mDownloaded = true;
                            Toast.makeText(context, "download complete" ,Toast.LENGTH_SHORT).show();

                        }
                    }
                }
            }
        }
    };

    private void startDownload(Uri uri) {
        mDownloadManager = (DownloadManager)getSystemService(Context.DOWNLOAD_SERVICE);
        DownloadManager.Request request = new DownloadManager.Request(uri);
        request.setTitle("title");
        request.setDescription("description");
        request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DCIM, "path");
        mDownloadingId = mDownloadManager.enqueue(request);
    }