Android - 在外部存儲器上使用其URL保存圖片

Question

我已經搜索並嘗試了一切，我在Google和StackOverflow上發現了關於此主題的所有內容，但是我沒有找到使其工作。 我有這個代碼，但它引發了我一個致命的例外。 我認爲，因爲我是Android新手，所以我做錯了一些事情。請幫助我^^

public void svgPhoto() throws IOException { 
    String dir = Environment.getExternalStorageDirectory().toString(); 
    OutputStream fos = null; 
    File file = new File(dir,"downloadImage.JPEG"); 
    Bitmap bm =BitmapFactory.decodeFile("http://perlbal.hi-pi.com/blog-images/3278/gd/1242316719/Chat-chat.jpg"); 
    fos = new FileOutputStream(file); 
    BufferedOutputStream bos = new BufferedOutputStream(fos); 
    bm.compress(Bitmap.CompressFormat.JPEG, 50, bos); 
    bos.flush(); 
    bos.close(); 

Answer 1

公共類下載擴展的AsyncTask {

 @Override 
     protected Void doInBackground(Void... params) 
        { 
      try { 
     URL url = new URL(imageURL); 
     file2 = new File(fileName); 


     long startTime = System.currentTimeMillis(); 

     /* Open a connection to that URL. */ 
     URLConnection ucon = url.openConnection(); 

     /* 
     * Define InputStreams to read from the URLConnection. 
     */ 
     InputStream is = ucon.getInputStream(); 
     BufferedInputStream bis = new BufferedInputStream(is); 

     /* 
     * Read bytes to the Buffer until there is nothing more to read(-1). 
     */ 
     ByteArrayBuffer baf = new ByteArrayBuffer(50); 
     int current = 0; 
     while ((current = bis.read()) != -1) { 
      baf.append((byte) current); 
     } 

     /* Convert the Bytes read to a String. */ 
     FileOutputStream fos = new FileOutputStream(file2); 
     fos.write(baf.toByteArray()); 
     fos.close(); 
     Log.d("ImageManager", 
       "download ready in" 
         + ((System.currentTimeMillis() - startTime)/1000) 
         + " sec"); 



    } catch (IOException e) { 

    } 
      return null; 
     } 

     @Override 
     protected void onPostExecute(Void result) { 
      super.onPostExecute(result); 
      try { 
       try { 

     File fileWithinMyDir = getApplicationContext().getFilesDir(); 
     String PATH = fileWithinMyDir.getAbsolutePath(); 


     Drawable d = Drawable.createFromPath(PATH.toString()); 
     Bitmap bmp = ((BitmapDrawable) d).getBitmap(); 

    } catch (Exception e) { 
     e.printStackTrace(); 
    } 

       if (dialog != null) { 
        if (dialog.isShowing()) { 
         dialog.dismiss(); 
        } 
       } 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 
     } 

    } 

Answer 2

嘗試下一編碼：

String dir = Environment.getExternalStorageDirectory().toString(); 

File outputfile = new File(dir+"/downloadImage.JPEG"); 
OutputStream fOut = null; 
try { 
fOut = new FileOutputStream(outputfile); 
Bitmap bm =BitmapFactory.decodeFile("http://perlbal.hi-pi.com/blog-images/3278/gd/1242316719/Chat-chat.jpg"); 
bm.compress(CompressFormat.JPEG, 50, fOut); 
} catch (IOException e) { 
Logger.error(e.getMessage(), e); 
}finally{ 
try { 
if(fOut != null){ 
fOut.flush(); 
fOut.close(); 
} 
} catch (IOException e) { 
Logger.error(e.getMessage(), e); 
} 
}