利用AsyncHttpClient实现图片的上传与下载

图片上传

       /**
 * @param path
 *            要上传的文件路径
 * @param url
 *            服务端接收URL
 * @throws Exception
 */
 public static void uploadFile(String path, String url) throws Exception {
 File file = new File(path);
 if (file.exists() && file.length() > 0) {
     AsyncHttpClient client = new AsyncHttpClient();
     RequestParams params = new RequestParams();
     params.put("uploadfile", file);
     // 上传文件
     client.post(url, params, new AsyncHttpResponseHandler() {
         @Override
         public void onSuccess(int statusCode, Header[] headers,
                 byte[] responseBody) {
             // 上传成功后要做的工作
             Toast.makeText(mContext, "上传成功", Toast.LENGTH_LONG).show();
             progress.setProgress(0);
         }

         @Override
         public void onFailure(int statusCode, Header[] headers,
                 byte[] responseBody, Throwable error) {
             // 上传失败后要做到工作
             Toast.makeText(mContext, "上传失败", Toast.LENGTH_LONG).show();
         }

         @Override
         public void onProgress(int bytesWritten, int totalSize) {
             // TODO Auto-generated method stub
             super.onProgress(bytesWritten, totalSize);
             int count = (int) ((bytesWritten * 1.0 / totalSize) * 100);
             // 上传进度显示
             progress.setProgress(count);
             Log.e("上传 Progress>>>>>", bytesWritten + " / " + totalSize);
         }

         @Override
         public void onRetry(int retryNo) {
             // TODO Auto-generated method stub
             super.onRetry(retryNo);
             // 返回重试次数
         }

     });
 } else {
     Toast.makeText(mContext, "文件不存在", Toast.LENGTH_LONG).show();
 }

图片下载

       /**
 * @param url
 *            要下载的文件URL
 * @throws Exception
 */
 public static void downloadFile(String url) throws Exception {

 AsyncHttpClient client = new AsyncHttpClient();
 // 指定文件类型
 String[] allowedContentTypes = new String[] { "image/png", "image/jpeg" };
 // 获取二进制数据如图片和其他文件
 client.get(url, new BinaryHttpResponseHandler(allowedContentTypes) {

     @Override
     public void onSuccess(int statusCode, Header[] headers,
             byte[] binaryData) {
         String tempPath = Environment.getExternalStorageDirectory()
                 .getPath() + "/temp.jpg";
         // TODO Auto-generated method stub
         // 下载成功后需要做的工作
         progress.setProgress(0);
         //
         Log.e("binaryData:", "共下载了：" + binaryData.length);
         //
         Bitmap bmp = BitmapFactory.decodeByteArray(binaryData, 0,
                 binaryData.length);

         File file = new File(tempPath);
         // 压缩格式
         CompressFormat format = Bitmap.CompressFormat.JPEG;
         // 压缩比例
         int quality = 100;
         try {
             // 若存在则删除
             if (file.exists())
                 file.delete();
             // 创建文件
             file.createNewFile();
             //
             OutputStream stream = new FileOutputStream(file);
             // 压缩输出
             bmp.compress(format, quality, stream);
             // 关闭
             stream.close();
             //
             Toast.makeText(mContext, "下载成功\n" + tempPath,
                     Toast.LENGTH_LONG).show();

         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }

     }

     @Override
     public void onFailure(int statusCode, Header[] headers,
             byte[] binaryData, Throwable error) {
         // TODO Auto-generated method stub
         Toast.makeText(mContext, "下载失败", Toast.LENGTH_LONG).show();
     }

     @Override
     public void onProgress(int bytesWritten, int totalSize) {
         // TODO Auto-generated method stub
         super.onProgress(bytesWritten, totalSize);
         int count = (int) ((bytesWritten * 1.0 / totalSize) * 100);
         // 下载进度显示
         progress.setProgress(count);
         Log.e("下载 Progress>>>>>", bytesWritten + " / " + totalSize);

     }

     @Override
     public void onRetry(int retryNo) {
         // TODO Auto-generated method stub
         super.onRetry(retryNo);
         // 返回重试次数
     }

 });

PHP服务端

 <?php
 $base_path = "./upload/"; // 接收文件目录
 $target_path = $base_path . basename ( $_FILES ['uploadfile'] ['name'] );
 if (move_uploaded_file ( $_FILES ['uploadfile'] ['tmp_name'], $target_path )) {
     $array = array (
             "code" => "1",
             "message" => $_FILES ['uploadfile'] ['name']
     );
     echo json_encode ( $array );
 } else {
     $array = array (
             "code" => "0",
             "message" => "There was an error uploading the file, please try again!" . $_FILES ['uploadfile'] ['error']
     );
     echo json_encode ( $array );
 }
 ?>

Service中类似的异常问题：

(com.zajt.zajtsafechat.http.AsyncHttpResponseHandler$ResponderHandler) {42843450} sending message to a Handler on a dead thread

解决办法：

 在Service中，AsyncHttpClient client = new SyncHttpClient();

 在Activity中，AsyncHttpClient client = new AsyncHttpClient();

其中SyncHttpClient是AsyncHttpClient的子类