Android中的图片上传问题

　　昨天做项目遇到上传图片的问题，服务端提供的接口如下，

　　

 /***
     * 上传文件
     * @param file  文件对象
     * @param filename 重命名
     * @return uuid  服务器文件的唯一标识，之后用于下载
     * @throws HttpException
     * @throws IOException
     */
    public static String upload(File file, String filename) throws HttpException, IOException {
        HttpClient client = new HttpClient();

        PostMethod postMethod = new PostMethod(UploadUrl);
        System.out.println("upload res " + filename);
        if(null == filename || "".equals(filename) || file == null) {
            return null;
        }
        Part[] p = new Part[2];
        p[0] = new StringPart("name", filename);
        p[1] = new FilePart("upload", filename, file);
        MultipartRequestEntity mrp =   new  MultipartRequestEntity(p , postMethod.getParams());

        postMethod.setRequestEntity(mrp);        
        client.executeMethod(postMethod);       

        String res = postMethod.getResponseBodyAsString();
        Pattern P = Pattern.compile(""uuid":"(.*)"");        
        Matcher m = P.matcher(res);

        String uuid;
        if(m.find() == true) {
            uuid = m.group(1);
        } else {
            uuid = null;
        }            

        return uuid;
    }

　　可以通过调用照相机和图库上传图片，这就遇到两个问题，图片过大导致imageview.setImageBitmap(bitmap);时程序就崩溃。

　　我的解决办法是，把图片另存到一个目录（类似于复制一份，或者生成一个缩略图，然后上传这张图片，每次重新上传时会吧就的图片覆盖，这样不会占用户太大空间）

　　代码如下

  picfromdoc.setOnClickListener(new OnClickListener() {//从图库找图片
              public void onClick(View v) {
                   Intent intent = new Intent(Intent.ACTION_PICK, null);
                  intent.setDataAndType(
                          MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");
                  startActivityForResult(intent, 0);
              }
          });
  picfromcam.setOnClickListener(new OnClickListener() {//调用照相机
 
             public void onClick(View v) {
                 Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                 intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(
                         Environment.getExternalStorageDirectory(), "jucanbao.jpg")));
                 startActivityForResult(intent, 1);
             }
         });

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == 1) {
            // 设置文件保存路径这里放在跟目录下
            Bitmap bitmap = BitmapFactory.decodeFile(Environment
                    .getExternalStorageDirectory().getPath()
                    + "/"
                    + "jucanbao.jpg");
            float wight = bitmap.getWidth();
            float height = bitmap.getHeight();
            bitmap = ZoomBitmap.zoomImage(upbitmap, wight / 5, height / 5);
            ByteArrayOutputStream stream = new ByteArrayOutputStream();
            bitmap.compress(Bitmap.CompressFormat.JPEG, 10, stream);
            saveMyBitmap("jucanbao", bitmap);
            imageview.setImageBitmap(bitmap);
        }

        if (requestCode == 0) {
            if (data != null) {
                Bitmap bitmap = BitmapFactory
                        .decodeFile(getAbsoluteImagePath(data.getData()));// 取相机图片的路径
                float wight = bitmap.getWidth();
                float height = bitmap.getHeight();
                bitmap = ZoomBitmap.zoomImage(bitmap, wight / 5, height / 5);
                ByteArrayOutputStream stream = new ByteArrayOutputStream();
                bitmap.compress(Bitmap.CompressFormat.JPEG, 10, stream);
                saveMyBitmap("jucanbao", bitmap);
                imageview.setImageBitmap(bitmap);
            }
        }
        super.onActivityResult(requestCode, resultCode, data);
    }

　　取相机图片绝对路径

    protected String getAbsoluteImagePath(Uri uri) {
        String[] proj = { MediaStore.Images.Media.DATA };
        Cursor cursor = managedQuery(uri, proj, 
                null, 
                null, 
                null); 

        int column_index = cursor
                .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        return cursor.getString(column_index);
    }

　　缩小图片

public static class ZoomBitmap {

        public static Bitmap zoomImage(Bitmap bgimage, double newWidth,
                double newHeight) {
            // 获取这个图片的宽和高
            float width = bgimage.getWidth();
            float height = bgimage.getHeight();
            // 创建操作图片用的matrix对象
            Matrix matrix = new Matrix();
            // 计算宽高缩放率
            float scaleWidth = ((float) newWidth) / width;
            float scaleHeight = ((float) newHeight) / height;
            // 缩放图片动作
            matrix.postScale(scaleWidth, scaleHeight);
            Bitmap bitmap = Bitmap.createBitmap(bgimage, 0, 0, (int) width,
                    (int) height, matrix, true);
            return bitmap;
        }
    }

　　保存图片

public static void saveMyBitmap(String id, Bitmap mBitmap) {// 生成图片
        File f = new File("/sdcard/" + id + ".jpg");
        try {
            f.createNewFile();

        } catch (IOException e) {
        }
        FileOutputStream fOut = null;
        try {
            fOut = new FileOutputStream(f);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        mBitmap.compress(Bitmap.CompressFormat.JPEG, 100, fOut);
        try {
            fOut.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
        try {
            fOut.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

　　最后调用文件上传的代码，将重新生成的图片上传即可。