将url文件下载到android的内部存储时出错？

Question

嗨，朋友们！我只是想将图像从url下载到内部存储设备http://github.com/google/fonts/blob/master/apache/roboto/Roboto-Regular.ttf?raw=true 。 我已经创建了目录。

        try
        {
        File folder = new File(getFilesDir() + "/"+"SS");
        if (!folder.exists())
        {
        folder.mkdir();
        Log.i("Directory","Created");
        }
        //URL connection 
        URL url = new URL(fonturl);
        HttpURLConnection c = (HttpURLConnection) 
        url.openConnection();
        c.connect();
        File apkStorage=new File(getFilesDir().getPath());
        Log.i("ApkStorage",""+apkStorage);
       outputFile=new File(apkStorage.getAbsolutePath() +"/");
            if(!outputFile.exists())
            {
            try {
                outputFile.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
            }
            Log.e("FIle", "File Created");
        }
        FileOutputStream fos = new FileOutputStream(outputFile);
        InputStream is = c.getInputStream();
        byte[] buffer = new byte[1024];
        int len1 = 0;
        while ((len1 = is.read(buffer)) != -1) {
            fos.write(buffer, 0, len1);
        }
        fos.close();
        is.close();
        }
        catch (Exception e) {
        e.printStackTrace();
        outputFile = null;
        Log.e("Error", "Download Error Exception " + e.getMessage());
        }
        }

它只是创建我指定的download.jpg文件名，而不是将文件从url下载到内部存储。

错误：未在我的目录中下载字体，显示错误，例如：Download Error Exception /data/user/0/sdk.nfnlabs.in.customfonts/files（是目录）。 应该将其直接下载到我的目录，例如roboto.tff，而不提供文件名。

Answer 1

您可以从HttpUrlConnection获取文件名，如下所示

HttpURLConnection c = (HttpURLConnection) url.openConnection();
c.connect();
File apkStorage = new File(getFilesDir().getPath());
Log.i("ApkStorage",""+apkStorage);
String raw = c.getHeaderField("Content-Disposition");
// raw = "attachment; filename=Roboto-Regular.ttf"
String fileName;
if(raw != null && raw.indexOf("=") != -1) {
    fileName = raw.split("=")[1]; //getting value after '='
} else {
    // fall back to random generated file name?
    fileName = "unknown_file";
}
outputFile = new File(apkStorage, fileName);

希望能对您有所帮助。

Answer 2

您可以使用以下功能

public void downloadFile(Context context){

    public long enqueue;
    public DownloadManager dm;

    dm = (DownloadManager) context.getSystemService(Context.DOWNLOAD_SERVICE);
    DownloadManager.Request request = new DownloadManager.Request(
            Uri.parse("http://github.com/google/fonts/blob/master/apache/roboto/Roboto-Regular.ttf?raw=true"));
    File direct = new File(Environment.getExternalStorageDirectory()
            + "/SS");

    if (!direct.exists()) {
        direct.mkdirs();
    }
    request.setAllowedNetworkTypes(
            DownloadManager.Request.NETWORK_WIFI
                    | DownloadManager.Request.NETWORK_MOBILE)
            .setAllowedOverRoaming(false).setTitle("Downloading...")
            .setDescription("Please wait. File is downloading...")
            .setDestinationInExternalPublicDir("/SS","Roboto-Regular.ttf")
            .setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);

    enqueue = dm.enqueue(request);



    context.registerReceiver(receiver, new IntentFilter(
            DownloadManager.ACTION_DOWNLOAD_COMPLETE));
}

广播接收器类用于了解天气下载是否完成。

public BroadcastReceiver receiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {

        String action = intent.getAction();
        if (DownloadManager.ACTION_DOWNLOAD_COMPLETE.equals(action)) {

            File direct = new File(Environment.getExternalStorageDirectory()
                    + "/SS");
            Toast.makeText(context,"File saved at location : "+direct.getAbsolutePath(),Toast.LENGTH_SHORT).show();

            context.unregisterReceiver(receiver);
            Activity_Downloads.callDownloadWS(context);

            long downloadId = intent.getLongExtra(
                    DownloadManager.EXTRA_DOWNLOAD_ID, 0);
            DownloadManager.Query query = new DownloadManager.Query();
            query.setFilterById(enqueue);
            Cursor c = dm.query(query);
            if (c.moveToFirst()) {
                int columnIndex = c
                        .getColumnIndex(DownloadManager.COLUMN_STATUS);
                if (DownloadManager.STATUS_SUCCESSFUL == c
                        .getInt(columnIndex)) {

                }
            }
        }
    }
};

并且不要忘记添加

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />