android HttpURLConnection获取图片

需求：从网络上获取图片验证码，原生httpconnection,代码如下:

注意：一定不要写到主线程里面，android 不支持主线程访问网络

 private class GetImagTask extends AsyncTask<Integer, Integer, Integer>{  
	        @Override  
	        protected Integer doInBackground(Integer... params) {  
	        	 URL imgUrl = null;  
	 	        Bitmap bitmap = null;  
	 	        try {  
	 	            imgUrl = new URL("http://192.168.54.82:8080/login.do?method=getimg");  
	 	            HttpURLConnection conn = (HttpURLConnection)imgUrl.openConnection();  
	 	            conn.setDoInput(true);  
	 	            conn.connect();  
	 	            InputStream is = conn.getInputStream();  
	 	            bitmap = BitmapFactory.decodeStream(is);  
	 	            is.close();  
	 	        } catch (MalformedURLException e) {  
	 	            // TODO Auto-generated catch block  
	 	            e.printStackTrace();  
	 	        }catch(IOException e){  
	 	            e.printStackTrace();  
	 	        }  
	 	       img_yzm.setImageBitmap(bitmap);
	            return null;  
	        }  
	    }  

这样就可以显示出来图片了