將字符串數組中的圖像保存到SD卡和手機庫

Question

我正在使用字符串數組來保存圖像，我從URL中獲取圖像。我有一個imageview，當它被移動時會改變其中的圖像。現在我想下載並保存SD卡上的任何圖像，並希望它出現在手機庫中的新文件夾中。

我使用下面的代碼，但它不工作，它沒有顯示任何錯誤。

private class ImageDownloadAndSave extends AsyncTask<String, Void, Bitmap> { 
     @Override 
     protected Bitmap doInBackground(String... arg0) { 
      downloadImagesToSdCard("", ""); 
      return null; 
     } 

     private void downloadImagesToSdCard(String downloadUrl, String imageName) { 
      try { 
       URL url = new URL(thumb[j]); 
       /* making a directory in sdcard */ 
       String sdCard = Environment.getExternalStorageDirectory() 
         .toString(); 
       File myDir = new File(sdCard, "test.jpg"); 

       /* if specified not exist create new */ 
       if (!myDir.exists()) { 
        myDir.mkdir(); 
        Log.v("", "inside mkdir"); 
       } 

       /* checks the file and if it already exist delete */ 
       String fname = imageName; 
       File file = new File(myDir, fname); 
       if (file.exists()) 
        file.delete(); 

       /* Open a connection */ 
       URLConnection ucon = url.openConnection(); 
       InputStream inputStream = null; 
       HttpURLConnection httpConn = (HttpURLConnection) ucon; 
       httpConn.setRequestMethod("GET"); 
       httpConn.connect(); 

       if (httpConn.getResponseCode() == HttpURLConnection.HTTP_OK) { 
        inputStream = httpConn.getInputStream(); 
       } 

       FileOutputStream fos = new FileOutputStream(file); 
       int totalSize = httpConn.getContentLength(); 
       int downloadedSize = 0; 
       byte[] buffer = new byte[1024]; 
       int bufferLength = 0; 
       while ((bufferLength = inputStream.read(buffer)) > 0) { 
        fos.write(buffer, 0, bufferLength); 
        downloadedSize += bufferLength; 
        Log.i("Progress:", "downloadedSize:" + downloadedSize 
          + "totalSize:" + totalSize); 
       } 

       fos.close(); 
       Log.d("test", "Image Saved in sdcard.."); 
      } catch (IOException io) { 
       io.printStackTrace(); 
      } catch (Exception e) { 
       e.printStackTrace(); 
      } 
     } 
    } 

，我通過

new ImageDownloadAndSave().execute(""); 

執行它在我的字符串數組的名稱是「大拇指」，這是保持所有的URL。我究竟做錯了什麼？

Answer 1

保存後應將圖像添加到圖庫中，然後對其進行掃描。請查看以下主題：

Image, saved to sdcard, doesn't appear in Android's Gallery app

MediaScannerConnection

Answer 2

文件需要被添加到Android MediaStore。這可以通過使用以下功能輕鬆完成。

public void scanFile(final File file) { 
    try { 
     new MediaScannerConnectionClient() { 
      private MediaScannerConnection mMs; 

      public void init() { 
       mMs = new MediaScannerConnection(myContext, this); 
       mMs.connect(); 
      } 

      @Override 
      public void onMediaScannerConnected() { 
       mMs.scanFile(file.getAbsolutePath(), null); 
       mMs.disconnect(); 
      } 

      @Override 
      public void onScanCompleted(String path, Uri uri) { 
      } 

     }.init(); 
    } catch(Exception e) { 
     // Device does not support adding files manually. 
     // Sending Broadcast to start MediaScanner (slower than adding manually) 
     try { 
      sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, 
        Uri.parse("file://" + Environment.getExternalStorageDirectory()))); 
     } catch(Exception ee) { 
      // Something went terribly wrong. 
      // Can't add file to MediaStore and can't send Broadcast to start MediaScanner. 
     } 
    } 
} 

你只需要一個行添加到您的代碼：

// ..... 

fos.close(); 
Log.d("test", "Image Saved in sdcard.."); 

scanFile(file); // <------------- add this