如何爲我的應用程序創建數據文件夾？

Question

我寫這段代碼用於下載我的android應用程序中的一些文件，但現在下載的文件在根目錄下沒有任何特殊的順序，它看起來非常糟糕！所以我想知道如何爲我的應用程序的下載文件添加一個文件夾？

碼字行解釋輸出的路徑：

OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/" + downloadedfileName); 

這裏是我的代碼：

private class DownloadFileFromURL extends AsyncTask<String, String, String> { 
     private String downloadedfileName; 
     private ProgressDialog pDialog; 

     @Override 
     protected void onPreExecute() { 
      super.onPreExecute(); 

      Toast.makeText(getApplicationContext(), "بارگذاری...", Toast.LENGTH_SHORT).show(); 
      pDialog = new ProgressDialog(DownloadActivity.this); 
      pDialog.setMessage("کتاب در حال بارگذاري، لطفا منتظر بمانيد..."); 
      pDialog.setIndeterminate(false); 
      pDialog.setCancelable(false); 
      pDialog.show(); 
     } 

     @Override 
     protected void onPostExecute(String result) { 
      // TODO Auto-generated method stub 
      pDialog.dismiss(); 
      AlertDialog.Builder builder = new AlertDialog.Builder(DownloadActivity.this) 
      .setTitle("دانلود کتاب با موفقیت انجام شد") 
      .setMessage("از دانلود شما سپاس‌گذاریم.") 
      .setNeutralButton("خواهش میکنم", new DialogInterface.OnClickListener() { 

       @Override 
       public void onClick(DialogInterface arg0, int arg1) { 
        Intent i = new Intent(DownloadActivity.this, LibActivity.class); 
        i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
        DownloadActivity.this.startActivity(i); 
        DownloadActivity.this.finish(); 
       } 
      }); 
    builder.create().show(); 
     } 
     public void setDownloadedFileName(String downloadedfileName){ 
      this.downloadedfileName = downloadedfileName; 
     } 

     /** 
     * Downloading file in background thread 
     * */ 
     @Override 
     protected String doInBackground(String... surl) { 
      int count; 
      try { 
       URL url = new URL(surl[0]); 
       URLConnection conection = url.openConnection(); 
       conection.connect(); 

       // this will be useful so that you can show a typical 0-100% 
       // progress bar 
       int lenghtOfFile = conection.getContentLength(); 

       // download the file 
       InputStream input = new BufferedInputStream(url.openStream(), 
         8192); 

       // Output stream 
       //OutputStream output = new FileOutputStream(Environment 
       //  .getExternalStorageDirectory().toString() 
       //  + "/data/" + downloadedfileName); 
       OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/ketabha/" + downloadedfileName); 

       byte data[] = new byte[1024]; 

       long total = 0; 

       while ((count = input.read(data)) != -1) { 
        total += count; 
        // publishing the progress.... 
        // After this onProgressUpdate will be called 
        // publishProgress("" + (int) ((total * 100)/lenghtOfFile)); 

        // writing data to file 
        output.write(data, 0, count); 
       } 

       // flushing output 
       output.flush(); 

       // closing streams 
       output.close(); 
       input.close(); 

      } catch (Exception e) { 
       Log.e("Error: ", e.getMessage()); 
      } 

      return null; 
     } 

    } 

Answer 1

一樣簡單更改爲您喜歡的目錄：

OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/ANYFOLDER/ANOTHERFOLDER/" + downloadedfileName); 

並記住，在第一個創建該目錄與此代碼：

File dir = new File(yourdirectory); 
if(!dir.exists()){ 
    dir.mkdirs(); 
} 

上面的代碼工作，如果你加入你的AndroidManifest.xml文件相關的清單：

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

和更多信息，請參見下面的鏈接：

How to create directory automatically on SD card
Create folder in Android
can't create a folder in external storage on android device